From cadc25ee89e505485e18df8cd36de679a5f51654 Mon Sep 17 00:00:00 2001 From: rrodriguze Date: Tue, 1 Oct 2019 23:01:34 +0200 Subject: Added spanish traduction for hq9+ --- es-es/hq9+-es.html.markdown | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 es-es/hq9+-es.html.markdown diff --git a/es-es/hq9+-es.html.markdown b/es-es/hq9+-es.html.markdown new file mode 100644 index 00000000..0e1a36e1 --- /dev/null +++ b/es-es/hq9+-es.html.markdown @@ -0,0 +1,44 @@ +--- +language: HQ9+ +filename: hq9+-es.html +contributors: + - ["Alexey Nazaroff", "https://github.com/rogaven"] +translators: + - ["Roberto R", "https://github.com/rrodriguze"] +lang: es-es +--- + +HQ9+ es una parodia de los lenguajes de programación esotéricos y fue creado +por Cliff Biffle. +El lenguaje tiene solo cuatro comandos y no está completo de Turing. + +``` +Solo hay cuatro comandos, representados por los siguientes cuatro caracteres +H: imprime "Hello, world!" +Q: imprime el código fuente del programa (ein Quine) +9: imprime la letra de "99 Bottles of Beer" ++: aumenta el acumulador en uno (el valod del acumulador no se puede leer) +Cualquier otro caracter es ignorado. + +Ok. Escribamos el programa: + HQ + +Resultado: + Hello world! + HQ + +HQ9+ es muy simple, pero te permite hacer cosas en él. Otros lenguajes son muy +difíciles.Por ejemplo, el siguiente programa imprime tres copias de sí mismo en +la pantalla: + QQQ +Esto imprime: + QQQ + QQQ + QQQ +``` + +Y esto es todo. Hay muchos intérpretes para HQ9+. +A continuación encontrarás uno de ellos. + ++ [One of online interpreters](https://almnet.de/esolang/hq9plus.php) ++ [HQ9+ official website](http://cliffle.com/esoterica/hq9plus.html) -- cgit v1.2.3 From 306b923cdc1bd2da0a418125f294c676b39619da Mon Sep 17 00:00:00 2001 From: rrodriguze Date: Tue, 1 Oct 2019 23:22:16 +0200 Subject: Added spanish traduction for pcre --- es-es/pcre-es.html.markdown | 84 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) create mode 100644 es-es/pcre-es.html.markdown diff --git a/es-es/pcre-es.html.markdown b/es-es/pcre-es.html.markdown new file mode 100644 index 00000000..279c9a39 --- /dev/null +++ b/es-es/pcre-es.html.markdown @@ -0,0 +1,84 @@ +--- +language: PCRE +filename: pcre-es.txt +contributors: + - ["Sachin Divekar", "http://github.com/ssd532"] +translators: + - ["Roberto R", "https://github.com/rrodriguze"] +lang: es-es +--- + +Una expresión regular (regex o regexp para abreviar) es una cadena especial +utilizada para definir un patrón, por ejemplo, buscar una secuencia de +caracteres; por ejemplo, `/^[a-z]+:/` se puede usar para extraer `http:` +desde la URL `http://github.com/`. + +PCRE (Pearl Compatible Regular Expressions) es una biblioteca para expresiones +muy similar a la Perls, desde ahí el nombre. Se trata de una de las sintaxis +más comunes para escribir expresiones regulares. + +Hay dos tipos de metacaracteres (caracteres con una función especial): + +* Caracteres reconocidos en todas partes excepto corchetes + +``` + \ caracter de escape + ^ buscar al principio de la cadena (o línea, en modo multilínea) + $ busca al final de la cadena (o línea, en modo multilínea) + . cualquier caracter exceptoo las nuevas líneas + [ inicio de clase de caracter + | condiciones alternativas del separador + ( inicio del subpatrón + ) fin del subpatrón + ? cuantificador "0 o 1" + * quantificatore "0 o más" + + quantificatore "1 o más" + { inicio de cuantificador numérico +``` + +* Caracteres reconocidos entre corchetes + +``` + \ caracter de escape + ^ negar la clase si es el primer caracter + - indica una serie de caracteres + [ clase de caracteres POSIX (si sigue la sintaxis POSIX) + ] termina la clase de caracteres +``` + +PCRE también proporciona clases de caracteres predefinidas + +``` + \d cifra decimal + \D cifra NO decimal + \h espacio horizontal vacío + \H espacio horizontal NO vacío + \s espacio + \S NO esoacui + \v espacio vertical vacío + \V espacio vertical NO vacío + \w palabra + \W "NO palabra" +``` + +## Ejemplos + +Usaremos la siguiente cadena para nuestras pruebas: + +``` +66.249.64.13 - - [18/Sep/2004:11:07:48 +1000] "GET /robots.txt HTTP/1.0" 200 468 "-" "Googlebot/2.1" +``` + +Se trata de una línea de log del servidor web Apache. + +| Regex | Resultado | Comentario | +| :---- | :-------------- | :------ | +| `GET` | GET | Busque exactamente la cadena "GET" (distingue entre mayúsculas y minúsculas) | +| `\d+.\d+.\d+.\d+` | 66.249.64.13 | `\d+` identifica uno o más (cuantificador `+`) números [0-9], `\.` identifica el caracter `.` | +| `(\d+\.){3}\d+` | 66.249.64.13 | `(\d+\.){3}` busca el grupo (`\d+\.`) exactamente 3 veces. | +| `\[.+\]` | [18/Sep/2004:11:07:48 +1000] | `.+` identifica cualquier caracter, excepto las nuevas líneas; `.` indica cualquier carácter | +| `^\S+` | 66.249.64.13 | `^` buscar al inicio de la cadena, `\S+` identifica la primera cadena de caracteres que no sea espacio | +| `\+[0-9]+` | +1000 | `\+` identifica el caracter `+`. `[0-9]` indica una cifra de 0 a 9. La expresión es equivalente a `\+\d+` | + +## Otros recursos +[Regex101](https://regex101.com/) - probador de expresiones regulares -- cgit v1.2.3 From 93fba1ffae651fbbe163f20dd642bd79ca8ca9d7 Mon Sep 17 00:00:00 2001 From: gaufung Date: Thu, 3 Oct 2019 19:18:39 +0800 Subject: [powershell/zh-cn] Add poweshell Simplified Chinsese version --- zh-cn/powershell-cn.html.markdown | 324 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 324 insertions(+) create mode 100644 zh-cn/powershell-cn.html.markdown diff --git a/zh-cn/powershell-cn.html.markdown b/zh-cn/powershell-cn.html.markdown new file mode 100644 index 00000000..ad5d50d3 --- /dev/null +++ b/zh-cn/powershell-cn.html.markdown @@ -0,0 +1,324 @@ +--- +category: tool +tool: powershell +contributors: + - ["Wouter Van Schandevijl", "https://github.com/laoujin"] +translators: + - ["Feng Gao", "https://github.com/gaufung"] +filename: LearnPowershell.ps1 +--- + +PowerShell 是 Windows 平台下的脚本语言同时也是配置管理框架，它是建立在微软 .Net Framework 之上，Windows 7 以及之后版本都内置 Poweshell。下面的示例中都是 PoweShell 脚本的一部分或者直接能够在 Shell 交互窗口中执行。 + +与 Bash 最大的不同是你大部分操作的东西是对象而不是普通的文本。 + +[延伸阅读](https://technet.microsoft.com/en-us/library/bb978526.aspx) + +如果你不确定你的环境，执行如下操作： + +```powershell +Get-ExecutionPolicy -List +Set-ExecutionPolicy AllSigned +# Execution Policy 包含以下： +# - Restricted: 不会运行脚本。 +# - RemoteSigned: 只会运行受信任的发行商下载的脚本。 +# - AllSigned: 运行需要被信任发行商签名的脚本。 +# - Unrestricted: 运行所有脚本 +help about_Execution_Policies # 查看更多信息 + +# 当前 PowerShell 版本 +$PSVersionTable +``` + +获取帮助 + +```powershell +# 查找命令 +Get-Command about_* # 别名: gcm +Get-Command -Verb Add +Get-Alias ps +Get-Alias -Definition Get-Process + +Get-Help ps | less # 别名: help +ps | Get-Member # 别名: gm + +Show-Command Get-EventLog # GUI 填充参数 + +Update-Help # 管理员运行 +``` + +接下来是教程 + +```powershell +# 正如你看到的，每一行开头是 # 都是注释 + +# 简单的 Hello World 实例 +echo Hello world! +# echo 是 Write-Output (cmdlet) 的别名 +# 大部分 cmdlet 和函数都遵循 "动词-名词" 命名规则。 + +# 每个命令都从新的一行开始或者是一个分号 +echo 'This is the first line'; echo 'This is the second line' + +# 声明一个变量如下： +$aString="Some string" +# 或者像这样： +$aNumber = 5 -as [double] +$aList = 1,2,3,4,5 +$anEmptyList = @() +$aString = $aList -join '--' # 也包含 join 方法 +$aHashtable = @{name1='val1'; name2='val2'} + +# 使用变量： +echo $aString +echo "Interpolation: $aString" +echo "$aString has length of $($aString.Length)" +echo '$aString' +echo @" +This is a Here-String +$aString +"@ +# 注意 ' (单引号) 不是变量的一部分 +# 在这里字符串也可以是单引号 + +# 内置变量: +# 下面是一些有用的内置变量，比如： +echo "Booleans: $TRUE and $FALSE" +echo "Empty value: $NULL" +echo "Last program's return value: $?" +echo "Exit code of last run Windows-based program: $LastExitCode" +echo "The last token in the last line received by the session: $$" +echo "The first token: $^" +echo "Script's PID: $PID" +echo "Full path of current script directory: $PSScriptRoot" +echo 'Full path of current script: ' + $MyInvocation.MyCommand.Path +echo "FUll path of current directory: $Pwd" +echo "Bound arguments in a function, script or code block: $PSBoundParameters" +echo "Unbound arguments: $($Args -join ', ')." +# 更多的内置类型: `help about_Automatic_Variables` + +# 内联其他文件 (点操作符) +. .\otherScriptName.ps1 + + +### 控制流 +# 下面是条件判断结构 +if ($Age -is [string]) { + echo 'But.. $Age cannot be a string!' +} elseif ($Age -lt 12 -and $Age -gt 0) { + echo 'Child (Less than 12. Greater than 0)' +} else { + echo 'Adult' +} + +# Switch 语句比其他语言更强大 +$val = "20" +switch($val) { + { $_ -eq 42 } { "The answer equals 42"; break } + '20' { "Exactly 20"; break } + { $_ -like 's*' } { "Case insensitive"; break } + { $_ -clike 's*'} { "clike, ceq, cne for case sensitive"; break } + { $_ -notmatch '^.*$'} { "Regex matching. cnotmatch, cnotlike, ..."; break } + { 'x' -contains 'x'} { "FALSE! -contains is for lists!"; break } + default { "Others" } +} + +# 经典的 For 循环 +for($i = 1; $i -le 10; $i++) { + "Loop number $i" +} +# 或者可以更简洁 +1..10 | % { "Loop number $_" } + +# PowerShell 还提供其他循环方式 +foreach ($var in 'val1','val2','val3') { echo $var } +# while () {} +# do {} while () +# do {} until () + +# 异常处理 +try {} catch {} finally {} +try {} catch [System.NullReferenceException] { + echo $_.Exception | Format-List -Force +} + + +### Providers +# 列出当前目录下的文件和子目录 +ls # 或者 `dir` +cd ~ # 回到主目录 + +Get-Alias ls # -> Get-ChildItem +# 这些 cmdlet 有更加通用的名称，因为它不仅仅只操作当前目录，这一点和其他脚本语言不同。 +cd HKCU: # 跳转 HKEY_CURRENT_USER 注册表中的值 + +# 获取当前会话中的提供者 +Get-PSProvider + + +### 管道 +# Cmdlets 中的参数用来控制它们的行为： +Get-ChildItem -Filter *.txt -Name # 获取所有 txt 文件名。 +# 需要输入足够多的参数来确保没有歧义。 +ls -fi *.txt -n # -f 是不可以的因为 -Force 同样存在。 +# 使用 `Get-Help Get-ChildItem -Full` 来查看全部参数。 + +# 之前 cmdlet 获取的结果输出可以作为一下个输入。 +# `$_` 指代当前管道处理的对象。 +ls | Where-Object { $_.Name -match 'c' } | Export-CSV export.txt +ls | ? { $_.Name -match 'c' } | ConvertTo-HTML | Out-File export.html + +# 如果对管道的对象感到疑惑，使用 `Get-Member` 来查看该对象的可使用的方法和属性。 +ls | Get-Member +Get-Date | gm + +# ` 是行连续标识符，或者在每一行结尾添加一个 | +Get-Process | Sort-Object ID -Descending | Select-Object -First 10 Name,ID,VM ` + | Stop-Process -WhatIf + +Get-EventLog Application -After (Get-Date).AddHours(-2) | Format-List + +# 使用 % 作为 ForEach-Object 的简称。 +(a,b,c) | ForEach-Object ` + -Begin { "Starting"; $counter = 0 } ` + -Process { "Processing $_"; $counter++ } ` + -End { "Finishing: $counter" } + +# Get-Process 返回包含三列的表 +# 第三列是使用 2 位精度数值表示 VM 属性 +# 计算出来的列也可以表示更多的信息: +# `@{name='lbl';expression={$_}` +ps | Format-Table ID,Name,@{n='VM(MB)';e={'{0:n2}' -f ($_.VM / 1MB)}} -autoSize + + +### 函数 +# [string] 注记是可选的。 +function foo([string]$name) { + echo "Hey $name, have a function" +} + +# 调用你的函数 +foo "Say my name" + +# 函数可以包含命名参数、参数的注记和可解析的文档 +<# +.SYNOPSIS +Setup a new website +.DESCRIPTION +Creates everything your new website needs for much win +.PARAMETER siteName +The name for the new website +.EXAMPLE +New-Website -Name FancySite -Po 5000 +New-Website SiteWithDefaultPort +New-Website siteName 2000 # ERROR! Port argument could not be validated +('name1','name2') | New-Website -Verbose +#> +function New-Website() { + [CmdletBinding()] + param ( + [Parameter(ValueFromPipeline=$true, Mandatory=$true)] + [Alias('name')] + [string]$siteName, + [ValidateSet(3000,5000,8000)] + [int]$port = 3000 + ) + BEGIN { Write-Verbose 'Creating new website(s)' } + PROCESS { echo "name: $siteName, port: $port" } + END { Write-Verbose 'Website(s) created' } +} + + +### 都是 .NET +# PS 中的字符串事实上就是 .NET 的 System.String 类型 +# 所有 .NET 方法和属性都可用 +'string'.ToUpper().Replace('G', 'ggg') +# 或者更加 PowerShell 一点 +'string'.ToUpper() -replace 'G', 'ggg' + +# 不确定这样的话 .NET 方法如何调用 +'string' | gm + +# 调用静态 .NET 方法的语法： +[System.Reflection.Assembly]::LoadWithPartialName('Microsoft.VisualBasic') + +# 注意 .NET 方法调用必须使用括号，然而 PS 函数调用不能使用括号； +# 如果你调用 cmdlet/PS 函数使用了括号，就相当于传递了参数列表。 +$writer = New-Object System.IO.StreamWriter($path, $true) +$writer.Write([Environment]::NewLine) +$writer.Dispose() + +### IO +# 从输入读入一个值 +$Name = Read-Host "What's your name?" +echo "Hello, $Name!" +[int]$Age = Read-Host "What's your age?" + +# Test-Path, Split-Path, Join-Path, Resolve-Path +# Get-Content filename # 返回字符串数组 string[] +# Set-Content, Add-Content, Clear-Content +Get-Command ConvertTo-*,ConvertFrom-* + + +### 有用的东西 +# 更新 PATH +$env:PATH = [System.Environment]::GetEnvironmentVariable("Path", "Machine") + + ";" + [System.Environment]::GetEnvironmentVariable("Path", "User") + +# 找到 Python 的 PATH +$env:PATH.Split(";") | Where-Object { $_ -like "*python*"} + +# 改变工作目录而不需要记住之前的路径 +Push-Location c:\temp # 改变工作目录至 c:\temp +Pop-Location # 改变到之前的工作目录 +# 别名: pushd 和 popd + +# 在下载之后解除目录阻塞 +Get-ChildItem -Recurse | Unblock-File + +# Windows 资源管理器打开当前目录 +ii . + +# 按任意键退出 +$host.UI.RawUI.ReadKey() +return + +# 创建快捷方式 +$WshShell = New-Object -comObject WScript.Shell +$Shortcut = $WshShell.CreateShortcut($link) +$Shortcut.TargetPath = $file +$Shortcut.WorkingDirectory = Split-Path $file +$Shortcut.Save() +``` + + +配置你的 PowerShell + +```powershell +# $Profile 是文件 `Microsoft.PowerShell_profile.ps1` 完整路径 +# 下面所有的代码都在 PS 会话开始的时候执行 +if (-not (Test-Path $Profile)) { + New-Item -Type file -Path $Profile -Force + notepad $Profile +} +# 更多信息: `help about_profiles` +# 更多关于 Shell 有用的信息，确保查看下面的 PSReadLine 项目。 +``` + +更多项目 + +* [Channel9](https://channel9.msdn.com/Search?term=powershell%20pipeline#ch9Search&lang-en=en) PowerShell 教程 +* [PSGet](https://github.com/psget/psget) PowerShell NuGet 包 +* [PSReadLine](https://github.com/lzybkr/PSReadLine/) 仿 bash 按行读取（ Window10 默认包含） +* [Posh-Git](https://github.com/dahlbyk/posh-git/) Git 命令提示 (推荐!) +* [PSake](https://github.com/psake/psake) 自动构建工作 +* [Pester](https://github.com/pester/Pester) BDD 测试框架 +* [Jump-Location](https://github.com/tkellogg/Jump-Location) Poweshell 中 `cd` 来跳转目录 +* [PowerShell Community Extensions](http://pscx.codeplex.com/) (废弃) + +尚未涉及 + +* WMI: Windows 管理规范 (Get-CimInstance) +* 多任务: Start-Job -scriptBlock {...}, +* 代码签名 +* 远程 (Enter-PSSession/Exit-PSSession; Invoke-Command) -- cgit v1.2.3 From b2e762307e064843059a5e649f3e7016032e8d74 Mon Sep 17 00:00:00 2001 From: Apoorv Choubey Date: Sat, 12 Oct 2019 21:08:56 +0530 Subject: add CSharp resource --- csharp.html.markdown | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/csharp.html.markdown b/csharp.html.markdown index df6544d3..139010c7 100644 --- a/csharp.html.markdown +++ b/csharp.html.markdown @@ -725,10 +725,10 @@ on a new line! ""Wow!"", the masses cried"; int _speed; // Everything is private by default: Only accessible from within this class. // can also use keyword private public string Name { get; set; } - + // Properties also have a special syntax for when you want a readonly property // that simply returns the result of an expression - public string LongName => Name + " " + _speed + " speed"; + public string LongName => Name + " " + _speed + " speed"; // Enum is a value type that consists of a set of named constants // It is really just mapping a name to a value (an int, unless specified otherwise). @@ -1089,7 +1089,7 @@ on a new line! ""Wow!"", the masses cried"; // Spell failed return false; } - // Other exceptions, or MagicServiceException where Code is not 42 + // Other exceptions, or MagicServiceException where Code is not 42 catch(Exception ex) when (LogException(ex)) { // Execution never reaches this block @@ -1213,7 +1213,7 @@ namespace Csharp7 Console.WriteLine(tt.GetLastName()); } } - + // PATTERN MATCHING class PatternMatchingTest { @@ -1320,3 +1320,4 @@ namespace Csharp7 * [ASP.NET Web Forms Tutorials](http://www.asp.net/web-forms/tutorials) * [Windows Forms Programming in C#](http://www.amazon.com/Windows-Forms-Programming-Chris-Sells/dp/0321116208) * [C# Coding Conventions](http://msdn.microsoft.com/en-us/library/vstudio/ff926074.aspx) + * [freeCodeCamp - C# Tutorial for Beginners](https://www.youtube.com/watch?v=GhQdlIFylQ8) -- cgit v1.2.3 From 17360e644f81f702d436e7d2230a1114abe16dcb Mon Sep 17 00:00:00 2001 From: Ygor Sad Date: Sun, 13 Oct 2019 19:36:14 -0300 Subject: [clojure/pt-br] Rewrite text to be more natural --- pt-br/clojure-pt.html.markdown | 599 +++++++++++++++++++++++++++-------------- 1 file changed, 391 insertions(+), 208 deletions(-) diff --git a/pt-br/clojure-pt.html.markdown b/pt-br/clojure-pt.html.markdown index b88d4eec..862d73ea 100644 --- a/pt-br/clojure-pt.html.markdown +++ b/pt-br/clojure-pt.html.markdown @@ -5,12 +5,13 @@ contributors: - ["Adam Bard", "http://adambard.com/"] translators: - ["Mariane Siqueira Machado", "https://twitter.com/mariane_sm"] + - ["Ygor Sad", "https://github.com/ysads"] lang: pt-br --- -Clojure é uma linguagem da família do Lisp desenvolvida para a JVM (máquina virtual Java). Possui uma ênfase muito mais forte em [programação funcional] (https://pt.wikipedia.org/wiki/Programa%C3%A7%C3%A3o_funcional) pura do que Common Lisp, mas inclui diversas utilidades [STM](https://en.wikipedia.org/wiki/Software_transactional_memory) para lidar com estado a medida que isso se torna necessário. +Clojure é uma linguagem da família do Lisp desenvolvida para a JVM (máquina virtual Java). Possui uma ênfase muito mais forte em [programação funcional] (https://pt.wikipedia.org/wiki/Programa%C3%A7%C3%A3o_funcional) pura do que Common Lisp, mas inclui diversos recursos [STM](https://en.wikipedia.org/wiki/Software_transactional_memory) para lidar com estado e mutabilidade, caso isso seja necessário. -Essa combinação permite gerenciar processamento concorrente de maneira muito simples, e frequentemente de maneira automática. +Essa combinação permite gerenciar processamento concorrente de maneira muito simples - frequentemente, de modo automático. (Sua versão de clojure precisa ser pelo menos 1.2) @@ -18,367 +19,549 @@ Essa combinação permite gerenciar processamento concorrente de maneira muito s ```clojure ; Comentários começam por ponto e vírgula -; Clojure é escrito em "forms", os quais são simplesmente -; listas de coisas dentro de parênteses, separados por espaços em branco. +; Código Clojure é escrito em formas - 'forms', em inglês. Tais estruturas são +; simplesmente listas de valores encapsuladas dentro de parênteses, separados por +; espaços em branco. -; O "reader" (leitor) de Clojure presume que o primeiro elemento de -; uma par de parênteses é uma função ou macro, e que os resto são argumentos. +; Ao interpretar um código em Clojure, o interpretador ou leitor - do inglês 'reader' - assume +; que o primeiro valor dentro de uma forma é uma função ou macro, de modo que os demais valores +; são seus argumentos. Isso se deve ao fato de que Clojure, por ser uma derivação de Lisp, +; usa notação prefixa (ou polonesa). -: A primeira chamada de um arquivo deve ser ns, para configurar o namespace (espaço de nomes) +; Num arquivo, a primeira chamada deve ser sempre para a função ns, +; que é responsável por definir em qual namespace o código em questão +; deve ser alocado (ns learnclojure) ; Alguns exemplos básicos: -; str cria uma string concatenando seus argumentos -(str "Hello" " " "World") ; => "Hello World" +; Aqui, str é uma função e "Olá" " " e "Mundo" são seus argumentos. O que ela faz é criar +; uma string concatenando seus argumentos. +(str "Olá" " " "Mundo") ; => "Olá Mundo" -; Cálculos são feitos de forma direta e intuitiva +; Note que espaços em branco separam os argumentos de uma função. Opcionalmente vírgulas +; podem ser usadas, se você quiser. +(str, "Olá", " ", "Mundo") ; => "Olá Mundo" + +; As operações matemáticas básicas usam os operadores de sempre (+ 1 1) ; => 2 (- 2 1) ; => 1 (* 1 2) ; => 2 (/ 2 1) ; => 2 -; Você pode comparar igualdade utilizando = +; Esses operadores aceitam um número arbitrário de argumentos +(+ 2 2 2) ; = 2 + 2 + 2 => 6 +(- 5 1 1) ; = 5 - 1 - 1 => 3 +(* 3 3 3 3) ; = 3 * 3 * 3 * 3 => 81 + +; Para verificar se dois valores são iguais, o operador = pode ser usado (= 1 1) ; => true (= 2 1) ; => false -; Negação para operações lógicas -(not true) ; => false +; Para saber se dois valores são diferentes +(not= 1 2) ; => true +(not (= 1 2)) ; => true -; Aninhar "forms" funciona como esperado +; Conforme vimos acima, é possível aninhar duas formas (+ 1 (- 3 2)) ; = 1 + (3 - 2) => 2 +(* (- 3 2) (+ 1 2)) ; = (3 - 2) * (1 + 2) => 3 + +; Se a leitura ficar comprometida, as fórmulas também podem ser escritas em múltiplas linhas +(* (- 3 2) + (+ 1 2)) ; => 3 +(* + (- 3 2) + (+ 1 2)) ; => 3 + ; Tipos ;;;;;;;;;;;;; -; Clojure usa os tipos de objetos de Java para booleanos, strings e números. -; Use `class` para inspecioná-los -(class 1) ; Literais Integer são java.lang.Long por padrão -(class 1.); Literais Float são java.lang.Double -(class ""); Strings são sempre com aspas duplas, e são java.lang.String +; Por ter interoperabilidade com Java, Clojure usa os tipos de objetos de Java para booleanos, +; strings e números. Para descobrir qual o tipo de um valor, você pode usar a função `class`: +(class 1234) ; Literais Integer são java.lang.Long por padrão +(class 1.50) ; Literais Float são java.lang.Double +(class "oi") ; Strings sempre usam aspas duplas e são java.lang.String (class false) ; Booleanos são java.lang.Boolean -(class nil); O valor "null" é chamado nil -; Se você quiser criar um lista de literais, use aspa simples para -; ela não ser avaliada -'(+ 1 2) ; => (+ 1 2) -; (que é uma abreviação de (quote (+ 1 2))) +; Tenha cuidado, ao dividir valores inteiros: +(= (/ 1 2) + (/ 1.0 2.0)) ; => false + +(class (/ 1 2)) ; => clojure.lang.Ratio +(class (/ 1.0 2.0)) ; => java.lang.Double + +; Aqui temos uma diferença em relação a Java, pois valores nulos são representados por `nil` +(class nil) ; nil -; É possível avaliar uma lista com aspa simples -(eval '(+ 1 2)) ; => 3 ; Coleções e sequências ;;;;;;;;;;;;;;;;;;; -; Listas são estruturas encadeadas, enquanto vetores são implementados como arrays. -; Listas e Vetores são classes Java também! -(class [1 2 3]); => clojure.lang.PersistentVector -(class '(1 2 3)); => clojure.lang.PersistentList +; Os dois tipos básicos de coleção são listas - "list" em inglês - e vetores - "vectors" +; no original. A principal diferença entre eles se +; dá pela implementação: +; - Vetores são implementados como arrays +; - Listas são listas ligadas +(class [1 2 3]) ; => clojure.lang.PersistentVector +(class '(1 2 3)) ; => clojure.lang.PersistentList -; Uma lista é escrita como (1 2 3), mas temos que colocar a aspa -; simples para impedir o leitor (reader) de pensar que é uma função. -; Também, (list 1 2 3) é o mesmo que '(1 2 3) +; Outra forma de declarar listas é usando a função list +(list 1 2 3) ; => '(1 2 3) -; "Coleções" são apenas grupos de dados -; Listas e vetores são ambos coleções: +; Clojure classifica conjuntos de dados de duas maneiras + +; "Coleções" são grupos simples de dados +; Tanto listas quanto vetores são coleções: (coll? '(1 2 3)) ; => true (coll? [1 2 3]) ; => true ; "Sequências" (seqs) são descrições abstratas de listas de dados. -; Apenas listas são seqs. +; Sequências - ou seqs - são conjuntos de dados com avaliação "lazy" +; Apenas listas são seqs: (seq? '(1 2 3)) ; => true (seq? [1 2 3]) ; => false -; Um seq precisa apenas prover uma entrada quando é acessada. -; Portanto, já que seqs podem ser avaliadas sob demanda (lazy) -- elas podem definir séries infinitas: -(range 4) ; => (0 1 2 3) -(range) ; => (0 1 2 3 4 ...) (uma série infinita) -(take 4 (range)) ; (0 1 2 3) +; Ter avaliação lazy significa que uma seq somente precisa prover uma informação quando +; ela for requisitada. Isso permite às seqs representar listas infinitas. +(range) ; => (0 1 2 3 4 ...) +(cycle [1 2]) ; => (1 2 1 2 1 2 ...) +(take 4 (range)) ; => (0 1 2 3) -; Use cons para adicionar um item no início de uma lista ou vetor +; A função cons é usada para adicionar um item ao início de uma lista ou vetor: (cons 4 [1 2 3]) ; => (4 1 2 3) (cons 4 '(1 2 3)) ; => (4 1 2 3) -; Conj adiciona um item em uma coleção sempre do jeito mais eficiente. -; Para listas, elas inserem no início. Para vetores, é inserido no final. +; Já conj adiciona um item em uma coleção sempre do jeito mais eficiente. +; Em listas, isso significa inserir no início. Já em vetores, ao final. (conj [1 2 3] 4) ; => [1 2 3 4] (conj '(1 2 3) 4) ; => (4 1 2 3) -; Use concat para concatenar listas e vetores +; Concatenação de coleções pode ser feita usando concat. Note que ela sempre gera uma +; seq como resultado e está sujeita a problemas de perfomance em coleções grandes, por +; conta da natureza lazy das seqs. +(concat '(1 2) [3 4]) ; => (1 2 3 4) (concat [1 2] '(3 4)) ; => (1 2 3 4) -; Use filter, map para interagir com coleções +; Outra forma de concatenar coleções é usando into. Ela não está sujeita a problemas +; com a avaliação lazy, mas o resultado final da ordem e do tipo dos argumentos passados +(into [1 2] '(3 4)) ; => [1 2 3 4] +(into '(1 2) [3 4]) ; => (4 3 1 2) + +; Note que em into a ordem dos parâmetros influencia a coleção final. +(into [1 2] '(3 4)) ; => (1 2 3 4) +(into '(1 2) [3 4]) ; => (4 3 1 2) + +; As funções filter e map podem ser usadas para interagir com as coleções. Repare que +; elas sempre retornam seqs, independentemente do tipo do seu argumento. (map inc [1 2 3]) ; => (2 3 4) -(filter even? [1 2 3]) ; => (2) +(filter even? [1 2 3 4]) ; => (2 4) + +; Use reduce reduzir coleções a um único valor. Também é possível passar um argumento +; para o valor inicial das operações +(reduce + [1 2 3]) ; = (+ (+ (+ 1 2) 3) 4) => 10 +(reduce + 10 [1 2 3 4]) ; = (+ (+ (+ (+ 10 1) 2) 3) 4) => 20 +(reduce conj [] '(3 2 1)) ; = (conj (conj (conj [] 3) 2) 1) => [3 2 1] + +; Reparou na semelhança entre listas e as chamadas de código Clojure? Isso se deve ao +; fato de que todo código clojure é escrito usando listas. É por isso que elas sempre +; são declaradas com o caracter ' na frente. Dessa forma o interpretador não tenta +; avaliá-las. +'(+ 2 3) ; cria uma lista com os elementos +, 2 e 3 +(+ 2 3) ; o interpretador chama a função + passando como argumentos 2 e 3 -; Use reduce para reduzi-los -(reduce + [1 2 3 4]) -; = (+ (+ (+ 1 2) 3) 4) -; => 10 +; Note que ' é apenas uma abreviação para a função quote. +(quote (1 2 3)) ; => '(1 2 3) + +; É possível passar uma lista para que o interpretador a avalie. Note que isso está +; sujeito ao primeiro elemento da lista ser um literal com um nome de uma função válida. +(eval '(+ 2 3)) ; => 5 +(eval '(1 2 3)) ; dá erro pois o interpretador tenta chamar a função 1, que não existe -; Reduce pode receber um argumento para o valor inicial -(reduce conj [] '(3 2 1)) -; = (conj (conj (conj [] 3) 2) 1) -; => [3 2 1] ; Funções ;;;;;;;;;;;;;;;;;;;;; -; Use fn para criar novas funções. Uma função sempre retorna -; sua última expressão. -(fn [] "Hello World") ; => fn +; Use fn para criar novas funções. Uma função sempre retorna sua última expressão. +(fn [] "Olá Mundo") ; => fn + +; Para executar suas funções, é preciso chamá-las, envolvendo-as em parênteses. +((fn [] "Olá Mundo")) ; => "Olá Mundo" + +; Como isso não é muito prático, você pode nomear funções atribuindo elas a literais. +; Isso torna muito mais fácil chamá-las: +(def ola-mundo (fn [] "Olá Mundo")) ; => fn +(ola-mundo) ; => "Olá Mundo" -; (É necessário colocar parênteses para chamá-los) -((fn [] "Hello World")) ; => "Hello World" +; Você pode abreviar esse processo usando defn: +(defn ola-mundo [] "Olá Mundo") -; Você pode atribuir valores a variáveis utilizando def -(def x 1) -x ; => 1 +; Uma função pode receber uma lista de argumentos: +(defn ola + [nome] + (str "Olá " nome)) +(ola "Jonas") ; => "Olá Jonas" -; Atribua uma função para uma var -(def hello-world (fn [] "Hello World")) -(hello-world) ; => "Hello World" +; É possível criar funções que recebam multivariadas, isto é, que aceitam números +; diferentes de argumentos: +(defn soma + ([] 0) + ([a] a) + ([a b] (+ a b))) -; Você pode abreviar esse processo usando defn -(defn hello-world [] "Hello World") +(soma) ; => 0 +(soma 1) ; => 1 +(soma 1 2) ; => 3 -; O [] é uma lista de argumentos para um função. -(defn hello [name] - (str "Hello " name)) -(hello "Steve") ; => "Hello Steve" +; Funções podem agrupar argumentos extras em uma seq: +(defn conta-args + [& args] + (str "Você passou " (count args) " argumentos: " args)) +(conta-args 1 2 3 4) ; => "Você passou 4 argumentos: (1 2 3 4)" -; Você pode ainda usar essa abreviação para criar funcões: -(def hello2 #(str "Hello " %1)) -(hello2 "Fanny") ; => "Hello Fanny" +; Você pode misturar argumentos regulares e argumentos em seq: +(defn ola-e-conta + [nome & args] + (str "Olá " nome ", você passou " (count args) " argumentos extras")) +(ola-e-conta "Maria" 1 2 3 4) ; => "Olá Maria, você passou 4 argumentos extras" -; Vocé pode ter funções multi-variadic, isto é, com um número variável de argumentos -(defn hello3 - ([] "Hello World") - ([name] (str "Hello " name))) -(hello3 "Jake") ; => "Hello Jake" -(hello3) ; => "Hello World" -; Funções podem agrupar argumentos extras em uma seq -(defn count-args [& args] - (str "You passed " (count args) " args: " args)) -(count-args 1 2 3) ; => "You passed 3 args: (1 2 3)" +; Nos exemplos acima usamos def para associar nomes a funções, mas poderíamos usá-lo +; para associar nomes a quaisquer valores: +(def xis :x) +xis ; => :x -; Você pode misturar argumentos regulares e argumentos em seq -(defn hello-count [name & args] - (str "Hello " name ", you passed " (count args) " extra args")) -(hello-count "Finn" 1 2 3) -; => "Hello Finn, you passed 3 extra args" +; Inclusive, tais literais podem possuir alguns caracteres não usuais em outras linguagens: +(def *num-resposta* 42) +(def conexao-ativa? true) +(def grito-de-medo! "AAAAAAA") +(def ->vector-vazio []) + +; É possível, inclusive, criar apelidos a nomes que já existem: +(def somar! soma) +(somar! 41 1) ; => 42 + +; Uma forma rápida de criar funções é por meio de funções anônimas. Elas são ótimas +; para manipulação de coleções e seqs, já que podem ser passadas para map, filter +; e reduce. Nessas funções, % é substituído por cada um dos items na seq ou na coleção: +(filter #(not= % nil) ["Joaquim" nil "Maria" nil "Antônio"]) ; => ("Joaquim" "Maria" "Antônio") +(map #(* % (+ % 2)) [1 2]) ; => (3 8) ; Mapas ;;;;;;;;;; -; Hash maps e array maps compartilham uma mesma interface. Hash maps são mais -; rápidos para pesquisa mas não mantém a ordem da chave. +; Existem dois tipos de mapas: hash maps e array maps. Ambos compartilham uma mesma +; interface e funções. Hash maps são mais rápidos para retornar dados, mas não mantém +; as chaves ordenadas. (class {:a 1 :b 2 :c 3}) ; => clojure.lang.PersistentArrayMap (class (hash-map :a 1 :b 2 :c 3)) ; => clojure.lang.PersistentHashMap -; Arraymaps pode automaticamente se tornar hashmaps através da maioria das -; operações se eles ficarem grandes o suficiente, portanto não há necessida de -; se preocupar com isso. - -;Mapas podem usar qualquer valor que se pode derivar um hash como chave +; Clojure converte automaticamente array maps em hash maps, por meio da maioria das +; funções de manipulação de mapas, caso eles fiquem grandes o suficiente. Não é +; preciso se preocupar com isso. - -; Mapas podem usar qualquer valor em que se pode derivar um hash como chave, -; mas normalmente palavras-chave (keywords) são melhores. -; Keywords são como strings mas com algumas vantagens. +; Chaves podem ser qualquer valor do qual possa ser obtido um hash, mas normalmente +; usam-se keywords como chave, por possuírem algumas vantagens. (class :a) ; => clojure.lang.Keyword -(def stringmap {"a" 1, "b" 2, "c" 3}) -stringmap ; => {"a" 1, "b" 2, "c" 3} +; Keywords são como strings, porém, duas keywords de mesmo valor são sempre armazenadas +; na mesma posição de memória, o que as torna mais eficientes. +(identical? :a :a) ; => true +(identical? (String. "a") (String. "a")) ; => false -(def keymap {:a 1, :b 2, :c 3}) -keymap ; => {:a 1, :c 3, :b 2} +(def mapa-strings {"a" 1 "b" 2 "c" 3}) +mapa-strings ; => {"a" 1, "b" 2, "c" 3} -; A propósito, vírgulas são sempre tratadas como espaçoes em branco e não fazem nada. +(def mapa-keywords {:a 1 :b 2 :c 3}) +mapa-keywords ; => {:a 1, :c 3, :b 2} -; Recupere o valor de um mapa chamando ele como uma função -(stringmap "a") ; => 1 -(keymap :a) ; => 1 +; Você pode usar um mapa como função para recuperar um valor dele: +(mapa-strings "a") ; => 1 +(mapa-keywords :a) ; => 1 -; Uma palavra-chave pode ser usada pra recuperar os valores de um mapa -(:b keymap) ; => 2 +; Se a chave buscada for uma keyword, ela também pode ser usada como função para recuperar +; valores. Note que isso não funciona com strings. +(:b mapa-keywords) ; => 2 +("b" mapa-strings) ; => java.lang.String cannot be cast to clojure.lang.IFn -; Não tente isso com strings -;("a" stringmap) -; => Exception: java.lang.String cannot be cast to clojure.lang.IFn +; Se você buscar uma chave que não existe, Clojure retorna nil: +(mapa-strings "d") ; => nil -; Buscar uma chave não presente retorna nil -(stringmap "d") ; => nil +; Use assoc para adicionar novas chaves em um mapa. +(def mapa-keywords-estendido (assoc mapa-keywords :d 4)) +mapa-keywords-estendido ; => {:a 1, :b 2, :c 3, :d 4} -; Use assoc para adicionar novas chaves para hash-maps -(def newkeymap (assoc keymap :d 4)) -newkeymap ; => {:a 1, :b 2, :c 3, :d 4} +; Mas lembre-se que tipos em Clojure são sempre imutáveis! Isso significa que o mapa +; inicial continua com as mesmas informações e um novo mapa, com mais dados, é criado +; a partir dele +mapa-keywords ; => {:a 1, :b 2, :c 3} -; Mas lembre-se, tipos em Clojure são sempre imutáveis! -keymap ; => {:a 1, :b 2, :c 3} +; assoc também pode ser usado para atualizar chaves: +(def outro-mapa-keywords (assoc mapa-keywords :a 0)) +outro-mapa-keywords ; => {:a 0, :b 2, :c 3} ; Use dissoc para remover chaves -(dissoc keymap :a :b) ; => {:c 3} +(dissoc mapa-keywords :a :b) ; => {:c 3} + +; Mapas também são coleções - mas não seqs! +(coll? mapa-keywords) ; => true +(seq? mapa-keywords) ; => false + +; É possível usar filter, map e qualquer outra função de coleções em mapas. +; Porém a cada iteração um vetor no formato [chave valor] vai ser passado como +; argumento. Por isso é conveniente usar funções anônimas. +(filter #(odd? (second %)) mapa-keywords) ; => ([:a 1] [:c 3]) +(map #(inc (second %)) mapa-keywords) ; => (2 3 4) ; Conjuntos ;;;;;; -(class #{1 2 3}) ; => clojure.lang.PersistentHashSet +; Conjuntos são um tipo especial de coleções que não permitem elementos repetidos. +; Eles podem ser criados com #{} ou com a função set. (set [1 2 3 1 2 3 3 2 1 3 2 1]) ; => #{1 2 3} +(class #{1 2 3}) ; => clojure.lang.PersistentHashSet -; Adicione um membro com conj -(conj #{1 2 3} 4) ; => #{1 2 3 4} +; Note que nem sempre um set vai armazenar seus elementos na ordem esperada. +(def meu-conjunto #{1 2 3}) +meu-conjunto ; => #{1 3 2} -; Remova um membro com disj -(disj #{1 2 3} 1) ; => #{2 3} +; Adição funciona normalmente com conj. +(conj meu-conjunto 4) ; => #{1 4 3 2} -; Test por existência usando set como função: -(#{1 2 3} 1) ; => 1 -(#{1 2 3} 4) ; => nil +; Remoção, no entanto, precisa ser feita com disj: +(disj meu-conjunto 1) ; => #{3 2} -; Existem muitas outras funções no namespace clojure.sets +; Para saber se um elemento está em um conjunto, use-o como função. Nesse aspecto +; conjuntos funcionam de maneira semelhante a mapas. +(meu-conjunto 1) ; => 1 +(meu-conjunto 4) ; => nil -; Forms úteis -;;;;;;;;;;;;;;;;; -; Construções lógicas em Clojure são como macros, e -; se parecem com as demais -(if false "a" "b") ; => "b" -(if false "a") ; => nil +; Condicionais e blocos +;;;;;;;;;;;;;;;;; -; Use let para criar um novo escopo associando sîmbolos a valores (bindings) +; Você pode usar um bloco let para criar um escopo local, no qual estarão disponíveis +; os nomes que você definir: (let [a 1 b 2] - (> a b)) ; => false + (+ a b)) ; => 3 -; Agrupe comandos juntos com "do" -(do - (print "Hello") - "World") ; => "World" (prints "Hello") +(let [cores {:yellow "Amarelo" :blue "Azul"} + nova-cor :red + nome-cor "Vermelho"] + (assoc cores nova-cor nome-cor)) ; => {:yellow "Amarelo", :blue "Azul", :red "Vermelho"} -; Funções tem um do implícito -(defn print-and-say-hello [name] - (print "Saying hello to " name) - (str "Hello " name)) -(print-and-say-hello "Jeff") ;=> "Hello Jeff" (prints "Saying hello to Jeff") +; Formas do tipo if aceitam três argumentos: a condição de teste, o comando a ser +; executado caso a condição seja positiva; e o comando para o caso de ela ser falsa. +(if true "a" "b") ; => "a" +(if false "a" "b") ; => "b" + +; Opcionalmente você pode não passar o último argumento, mas se a condição for falsa +; o if vai retornar nil. +(if false "a") ; => nil + +; A forma if somente aceita um comando para ser executado em cada caso. Se você +; precisar executar mais comandos, você pode usar a função do: +(if true + (do + (print "Olá ") + (print "Mundo"))) ; => escreve "Olá Mundo" na saída + +; Se você só deseja tratar o caso de sua condição ser verdadeira, o comando when é +; uma alternativa melhor. Seu comportamento é idêntico a um if sem condição negativa. +; Uma de suas vantagens é permitir a execução de vários comandos sem exigir do: +(when true "a") ; => "a" +(when true + (print "Olá ") + (print "Mundo")) ; => também escreve "Olá Mundo" na saída + +; Isso ocorre porque when possui um bloco do implícito. O mesmo se aplica a funções e +; comandos let: +(defn escreve-e-diz-xis + [nome] + (print "Diga xis, " nome) + (str "Olá " nome)) +(escreve-e-diz-xis "João") ;=> "Olá João", além de escrever "Diga xis, João" na saída. + +(let [nome "Nara"] + (print "Diga xis, " nome) + (str "Olá " nome)) ;=> "Olá João", além de escrever "Diga xis, João" na saída. -; Assim como let -(let [name "Urkel"] - (print "Saying hello to " name) - (str "Hello " name)) ; => "Hello Urkel" (prints "Saying hello to Urkel") ; Módulos ;;;;;;;;;;;;;;; -; Use "use" para poder usar todas as funções de um modulo +; Você pode usar a função use para carregar todas as funções de um módulo. (use 'clojure.set) -; Agora nós podemos usar operações com conjuntos +; Agora nós podemos usar operações de conjuntos definidas nesse módulo: (intersection #{1 2 3} #{2 3 4}) ; => #{2 3} (difference #{1 2 3} #{2 3 4}) ; => #{1} -; Você pode escolher um subconjunto de funções para importar -(use '[clojure.set :only [intersection]]) - -; Use require para importar um módulo +; Isso porém não é uma boa prática pois dificulta saber de qual módulo cada função +; veio, além de expor o código a conflitos de nomes, caso dois módulos diferentes +; definam funções com o mesmo nome. A melhor forma de referenciar módulos é por meio +; de require: (require 'clojure.string) -; Use / para chamar funções de um módulo +; Com isso podemos chamar as funções de clojure.string usando o operador / ; Aqui, o módulo é clojure.string e a função é blank? (clojure.string/blank? "") ; => true -; Você pode dar para um módulo um nome mais curto no import +; Porém isso não é muito prático, por isso é possível dar para um nome mais curto para +; o módulo ao carregá-lo: (require '[clojure.string :as str]) -(str/replace "This is a test." #"[a-o]" str/upper-case) ; => "THIs Is A tEst." -; (#"" denota uma expressão regular literal) +(str/replace "alguém quer teste?" #"[aeiou]" str/upper-case) ; => "AlgUém qUEr tEstE?" -; Você pode usar require (e até "use", mas escolha require) de um namespace utilizando :require. -; Não é necessário usar aspa simples nos seus módulos se você usar desse jeito. +; Nesse exemplo usamos também a construção #"", que delimita uma expressão regular. + +; É possível carregar outros módulos direto na definição do namespace. Note que nesse +; contexto não é preciso usar ' antes do vetor que define a importação do módulo. (ns test (:require [clojure.string :as str] [clojure.set :as set])) + +; Operadores thread +;;;;;;;;;;;;;;;;; + +; Uma das funções mais interessantes de clojure são os operadores -> e ->> - respectivamente +; thread-first e thread-last macros. Elas permitem o encadeamento de chamadas de funções, +; sendo perfeitas para melhorar a legibilidade em transformações de dados. + +; -> usa o resultado de uma chamada como o primeiro argumento da chamada à função seguinte: +(-> " uMa StRIng com! aLG_uNs ##problemas. " + (str/replace #"[!#_]" "") + (str/replace #"\s+" " ") + str/trim ; se a função só aceitar um argumento, não é preciso usar parênteses + (str/lower-case)) ; => "uma string com alguns problemas." + +; Na thread uma string com vários problemas foi passada como primeiro argumento à função +; str/replace, que criou uma nova string, a partir da original, porém somente com caracteres +; alfabéticos. Essa nova string foi passada como primeiro argumento para a chamada str/replace +; seguinte, que criou uma nova string sem espaços duplos. Essa nova string foi então passada +; como primeiro argumento para str/trim, que removeu espaços de seu início e fim, passando essa +; última string para str/lower-case, que a converteu para caracteres em caixa baixa. + +; ->> é equivalente a ->, porém o retorno de cada função é passado como último argumento da +; função seguinte. Isso é particularmente útil para lidar com seqs, já que as funções que +; as manipulam sempre as tomam como último argumento. +(->> '(1 2 3 4) + (filter even?) ; => '(2 4) + (map inc) ; => '(3 5) + (reduce *)) ; => 15 + + ; Java ;;;;;;;;;;;;;;;;; -; Java tem uma biblioteca padrão enorme e muito útil, -; portanto é importante aprender como utiliza-la. +; A biblioteca padrão de Java é enorme e possui inúmeros algoritmos e estruturas de +; dados já implementados. Por isso é bastante conveniente saber como usá-la dentro +; de Clojure. -; Use import para carregar um modulo java +; Use import para carregar um módulo Java. (import java.util.Date) -; Você pode importar usando ns também. +; Você pode importar classes Java dentro de ns também: (ns test (:import java.util.Date - java.util.Calendar)) + java.util.Calendar + java.util.ArrayList)) ; Use o nome da clase com um "." no final para criar uma nova instância -(Date.) ; +(def instante (Date.)) +(class instante) => ; java.util.Date + +; Para chamar um método, use o operador . com o nome do método. Outra forma é +; usar simplesmente . +(. instante getTime) ; => retorna um inteiro representando o instante +(.getTime instante) ; => exatamente o mesmo que acima -; Use . para chamar métodos. Ou, use o atalho ".method" -(. (Date.) getTime) ; -(.getTime (Date.)) ; exatamente a mesma coisa. +; Para chamar métodos estáticos dentro de classes Java, use / +(System/currentTimeMillis) ; => retorna um timestamp -; Use / para chamar métodos estáticos -(System/currentTimeMillis) ; (o módulo System está sempre presente) +; Note que não é preciso importar o módulo System, pois ele está sempre presente + +; Caso queira submeter uma instância de uma classe mutável a uma sequência de operações, +; você pode usar a função doto. Ela é funciona de maneira semelhante à função -> - ou +; thread-first -, exceto pelo fato de que ele opera com valores mutáveis. +(doto (java.util.ArrayList.) + (.add 11) + (.add 3) + (.add 7) + (java.util.Collections/sort)) ; => # -; Use doto para pode lidar com classe (mutáveis) de forma mais tolerável -(import java.util.Calendar) -(doto (Calendar/getInstance) - (.set 2000 1 1 0 0 0) - .getTime) ; => A Date. set to 2000-01-01 00:00:00 ; STM ;;;;;;;;;;;;;;;;; -; Software Transactional Memory é o mecanismo que Clojure usa para gerenciar -; estado persistente. Tem algumas construções em Clojure que o utilizam. +; Até aqui usamos def para associar nomes a valores. Isso, no entanto, possui algumas +; limitações, já que, uma vez definido essa associação, não podemos alterar o valor +; para o qual um nome aponta. Isso significa que nomes definidos com def não se +; comportam como as variáveis de outras linguagens. + +; Para lidar com estado persistente e mutação de valores, Clojure usa o mecanismo Software +; Transactional Memory. O atom é o mais simples de todos. Passe pra ele um valor inicial e +; e ele criará um objeto que é seguro de atualizar: +(def atom-mapa (atom {})) + +; Para acessar o valor de um atom, você pode usar a função deref ou o operador @: +@atom-mapa ; => {} +(deref atom-mapa) ; => {} -; O atom é o mais simples. Passe pra ele um valor inicial -(def my-atom (atom {})) +; Para mudar o valor de um atom, você deve usar a função swap! +; O que ela faz é chamar a função passada usando o atom como seu primeiro argumento. Com +; isso, ela altera o valor do atom de maneira segura. +(swap! atom-mapa assoc :a 1) ; Atribui a atom-mapa o resultado de (assoc {} :a 1) +(swap! atom-mapa assoc :b 2) ; Atribui a atom-mapa o resultado de (assoc {:a 1} :b 2) -; Atualize o atom com um swap!. -; swap! pega uma função e chama ela com o valor atual do atom -; como primeiro argumento, e qualquer argumento restante como o segundo -(swap! my-atom assoc :a 1) ; Coloca o valor do átomo my-atom como o resultado de (assoc {} :a 1) -(swap! my-atom assoc :b 2) ; Coloca o valor do átomo my-atom como o resultado de (assoc {:a 1} :b 2) +; Observe que essas chamadas alteraram de fato o valor de atom-mapa. Seu novo valor é: +@atom-mapa ; => {:a 1 :b 2} -; Use '@' para desreferenciar um atom e acessar seu valor -my-atom ;=> Atom<#...> (Retorna o objeto do Atom) -@my-atom ; => {:a 1 :b 2} +; Isso é diferente de fazer: +(def atom-mapa-2 (atom {})) +(def atom-mapa-3 (assoc @atom-mapa-2 :a 1)) -; Abaixo um contador simples usando um atom -(def counter (atom 0)) -(defn inc-counter [] - (swap! counter inc)) +; Nesse exemplo, atom-mapa-2 permanece com o seu valor original e é gerado um novo mapa, +; atom-mapa-3, que contém o valor de atom-mapa-2 atualizado. Note que atom-mapa-3 é um +; simples mapa, e não uma instância de um atom +@atom-mapa-2 ; => {} +atom-mapa-3 ; => {:a 1} -(inc-counter) -(inc-counter) -(inc-counter) -(inc-counter) -(inc-counter) +(class atom-mapa-2) ; => clojure.lang.Atom +(class atom-mapa-3) ; => clojure.lang.PersistentArrayMap -@counter ; => 5 +; A ideia é que o valor do atom só será atualizado se, após ser executada a função passada +; para swap!, o atom ainda estiver com o mesmo valor de antes. Isto é, se durante a execução +; da função alguém alterar o valor do atom, swap! reexecutará a função recebida usando o valor +; atual do átoma como argumento. -; Outras construção STM são refs e agents. +; Isso é ótimo em situações nas quais é preciso garantir a consistência de algum valor - tais +; como sistemas bancários e sites de compra. Para mais exemplos e informações sobre outras +; construções STM: + +; Exemplos e aplicações: https://www.braveclojure.com/zombie-metaphysics/ ; Refs: http://clojure.org/refs ; Agents: http://clojure.org/agents ``` ### Leitura adicional -Esse tutorial está longe de ser exaustivo, mas deve ser suficiente para que você possa começar. +Esse tutorial está longe de ser completo, mas deve ser suficiente para que você possa dar seus primeiros passos em Clojure. +Caso queira aprender mais: -Clojure.org tem vários artigos: +* clojure.org tem vários artigos: [http://clojure.org/](http://clojure.org/) -Clojuredocs.org tem documentação com exemplos para quase todas as funções principais (pertecentes ao core): +* Brave Clojure possui um e-book que explora em profundidade diversos recursos de clojure, incluindo ótimos exemplos: +[https://www.braveclojure.com/](https://www.braveclojure.com/) + +* clojuredocs.org tem documentação com exemplos para quase todas as funções principais (pertecentes ao core): [http://clojuredocs.org/quickref/Clojure%20Core](http://clojuredocs.org/quickref/Clojure%20Core) -4Clojure é um grande jeito de aperfeiçoar suas habilidades em Clojure/Programação Funcional: +* 4clojure possui alguns problemas e desafios interessantes para quem quiser treinar clojure ou programação funcional: [http://www.4clojure.com/](http://www.4clojure.com/) -Clojure-doc.org tem um bom número de artigos para iniciantes: +* clojure-doc.org tem um bom número de artigos para iniciantes: [http://clojure-doc.org/](http://clojure-doc.org/) -- cgit v1.2.3 From d03ff9338abb42ffc09a52af9b55f7addc1f88ba Mon Sep 17 00:00:00 2001 From: Miltiadis Stouras Date: Mon, 14 Oct 2019 13:49:03 +0300 Subject: Add some resources for Dynamic Programming --- dynamic-programming.html.markdown | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/dynamic-programming.html.markdown b/dynamic-programming.html.markdown index c73b1845..5d260206 100644 --- a/dynamic-programming.html.markdown +++ b/dynamic-programming.html.markdown @@ -3,6 +3,7 @@ category: Algorithms & Data Structures name: Dynamic Programming contributors: - ["Akashdeep Goel", "http://github.com/akashdeepgoel"] + - ["Miltiadis Stouras", "https://github.com/mstou"] --- # Dynamic Programming @@ -48,6 +49,15 @@ for i=0 to n-1 ## Online Resources -* [codechef](https://www.codechef.com/wiki/tutorial-dynamic-programming) +* MIT 6.006: [Lessons 19,20,21,22](https://www.youtube.com/playlist?list=PLUl4u3cNGP61Oq3tWYp6V_F-5jb5L2iHb) +* TopCoder: [Dynamic Programming from Novice to Advanced](https://www.topcoder.com/community/data-science/data-science-tutorials/dynamic-programming-from-novice-to-advanced/) +* [CodeChef](https://www.codechef.com/wiki/tutorial-dynamic-programming) * [InterviewBit](https://www.interviewbit.com/courses/programming/topics/dynamic-programming/) - +* GeeksForGeeks: + * [Overlapping Subproblems](https://www.geeksforgeeks.org/dynamic-programming-set-1/) + * [Tabulation vs Memoization](https://www.geeksforgeeks.org/tabulation-vs-memoizatation/) + * [Optimal Substructure Property](https://www.geeksforgeeks.org/dynamic-programming-set-2-optimal-substructure-property/) + * [How to solve a DP problem](https://www.geeksforgeeks.org/solve-dynamic-programming-problem/) +* [How to write DP solutions](https://www.quora.com/Are-there-any-good-resources-or-tutorials-for-dynamic-programming-DP-besides-the-TopCoder-tutorial/answer/Michal-Danilák) + +And a [quiz](https://www.commonlounge.com/discussion/cdbbfe83bcd64281964b788969247253) to test your knowledge. -- cgit v1.2.3 From 33211b82f73a3f04a6adb8aa691f82ae767b5ae7 Mon Sep 17 00:00:00 2001 From: Amey Bhavsar Date: Mon, 14 Oct 2019 20:04:48 +0530 Subject: Minor spelling mistake corrected On line 144, it was _per_, instead of _pre_ --- latex.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/latex.html.markdown b/latex.html.markdown index c980f5e5..e8bc6064 100644 --- a/latex.html.markdown +++ b/latex.html.markdown @@ -141,7 +141,7 @@ Operators are essential parts of a mathematical document: trigonometric functions ($\sin$, $\cos$, $\tan$), logarithms and exponentials ($\log$, $\exp$), limits ($\lim$), etc.\ -have per-defined LaTeX commands. +have pre-defined LaTeX commands. Let's write an equation to see how it's done: $\cos(2\theta) = \cos^{2}(\theta) - \sin^{2}(\theta)$ -- cgit v1.2.3 From 3996c22a891bb49018e2d80fa7b75fbd6e67e223 Mon Sep 17 00:00:00 2001 From: Chariton Charitonidis Date: Sat, 19 Oct 2019 16:01:29 +0300 Subject: add greek translation for python3 --- el-gr/python3-gr.html.markdown | 1030 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1030 insertions(+) create mode 100644 el-gr/python3-gr.html.markdown diff --git a/el-gr/python3-gr.html.markdown b/el-gr/python3-gr.html.markdown new file mode 100644 index 00000000..08c3d4aa --- /dev/null +++ b/el-gr/python3-gr.html.markdown @@ -0,0 +1,1030 @@ +--- +language: python3 +contributors: + - ["Louie Dinh", "http://pythonpracticeprojects.com"] + - ["Steven Basart", "http://github.com/xksteven"] + - ["Andre Polykanine", "https://github.com/Oire"] + - ["Zachary Ferguson", "http://github.com/zfergus2"] + - ["evuez", "http://github.com/evuez"] + - ["Rommel Martinez", "https://ebzzry.io"] + - ["Roberto Fernandez Diaz", "https://github.com/robertofd1995"] +filename: learnpython3.py +--- + +Η Python δημιουργήθηκε από τον Guido van Rossum στις αρχές των 90s. Πλέον είναι μία από τις πιο +δημοφιλείς γλώσσες. Ερωτευεται κανείς την python για τη συντακτική της απλότητα. +Βασικά είναι εκτελέσιμος ψευδοκώδικας. + +Το Feedback είναι πάντα δεκτό! Μπορείτε να με βρείτε στο [@haritonaras](http://twitter.com/haritonaras) +ή τον αρχικό συγγραφέα στο [@louiedinh](http://twitter.com/louiedinh) ή στο +louiedinh [at] [google's email service] + +Σημείωση: Το παρόν άρθρο ασχολείται μόνο με την Python 3. Δείτε [εδώ](http://learnxinyminutes.com/docs/python/) αν θέλετε να μάθετε την παλιά Python 2.7 + +```python + +# Τα σχόλια μίας γραμμής ξεκινούν με # + +""" Τα σχόλια πολλαπλών γραμμών μπορούν + να γραφούν με τρία ", και συχνά χρησιμοποιούνται + ως documentation. +""" + +#################################################### +## 1. Primitive (πρωταρχικοί) Τύποι Δεδομένων και Τελεστές +#################################################### + +# Αφού έχει αριθμούς +3 # => 3 + +# Λογικά θα έχει και Μαθηματικά... +1 + 1 # => 2 +8 - 1 # => 7 +10 * 2 # => 20 +35 / 5 # => 7.0 + +# Η διαίρεση ακεραίων κάνει στρογγυλοποίηση προς τα κάτω για θετικούς και αρνητικούς αριθμούς +5 // 3 # => 1 +-5 // 3 # => -2 +5.0 // 3.0 # => 1.0 # works on floats too +-5.0 // 3.0 # => -2.0 + +# Το αποτέλεσμα της διαίρεσης είναι πάντα float +10.0 / 3 # => 3.3333333333333335 + +# Modulo τελεστής +7 % 3 # => 1 + +# Ύψωση σε δύναμη (x**y, x στην y-οστή δύναμη) +2**3 # => 8 + +# Ελέγχουμε την προτεραιότητα πράξεων με παρενθέσεις +(1 + 3) * 2 # => 8 + +# Οι Boolean τιμές είναι primitives (Σημ.: τα κεφαλαία) +True +False + +# άρνηση με το not +not True # => False +not False # => True + +# Boolean τελεστές +# Σημ. ότι τα "and" και "or" είναι case-sensitive +True and False # => False +False or True # => True + +# Τα True και False είναι 1 και 0 αλλά με διαφορετικά keywords +True + True # => 2 +True * 8 # => 8 +False - 5 # => -5 + +# Μπορούμε να δούμε τις αριθμητικές τιμές των True και False μέσω των τελεστών σύγκρισης +0 == False # => True +1 == True # => True +2 == True # => False +-5 != False # => True + +# Χρησιμοποιώντας τελεστές boolean σε ακεραίους, οι ακέραιοι γίνονται cast σε +# boolean ώστε να γίνει η αποτίμηση της έκφρασης. +# Το αποτέλεσμα όμως είναι non-cast, δηλαδή ίδιου τύπου με τα αρχικά ορίσματα +# Μην μπερδεύετε τις bool(ints) και bitwise and/or (&,|) +bool(0) # => False +bool(4) # => True +bool(-6) # => True +0 and 2 # => 0 +-5 or 0 # => -5 + +# Ισότητα == +1 == 1 # => True +2 == 1 # => False + +# Διάφορο != +1 != 1 # => False +2 != 1 # => True + +# Περισσότερες συγκρίσεις +1 < 10 # => True +1 > 10 # => False +2 <= 2 # => True +2 >= 2 # => True + +# Κοιτάζουμε αν μία τιμή ανήκει σε ένα εύρος +1 < 2 and 2 < 3 # => True +2 < 3 and 3 < 2 # => False +# Το Chaining (αλυσίδωση? :P) κάνει το παραπάνω πιο όμορφα +1 < 2 < 3 # => True +2 < 3 < 2 # => False + +# (is vs. ==) το is ελέγχει αν δύο μεταβλητές αναφέρονται στο ίδιο αντικείμενο, +# αλλά το == ελέγχει αν τα αντικείμενα στα οποία αναφέρονται οι μεταβλητές έχουν τις ίδιες τιμές +a = [1, 2, 3, 4] # το a δείχνει σε μία νέα λίστα, [1,2,3,4] +b = a # το b δείχνει στο αντικείμενο που δείχνει το a +b is a # => True, a και b αναφέρονται στο ίδιο αντικείμενο +b == a # => True, τα αντικείμενα των a κι b είναι ίσα +b = [1, 2, 3, 4] # Το b δείχνει σε μία νέα λίστα, [1, 2, 3, 4] +b is a # => False, a και b δεν αναφέρονται στο ίδιο αντικείμενο +b == a # => True, τα αντικείμενα των a και b είναι ίσα + +# Τα Strings (συμβολοσειρές) δημιουργούνται με " ή ' +"This is a string." +'This is also a string.' + +# Μπορούμε και να προσθέτουμε Strings, αλλά προσπαθήστε να μην το κάνετε +"Hello " + "world!" # => "Hello world!" +# Τα String literals (αλλά όχι οι μεταβλητές) μπορούν να συντμιθούν και χωρίς το '+' +"Hello " "world!" # => "Hello world!" + +# Μπορούμε να φερθούμε σε string σαν να είναι λίστα από χαρακτήρες +"This is a string"[0] # => 'T' + +# Μπορούμε να βρούμε το μήκος ενός string +len("This is a string") # => 16 + +# Το .format μπορεί να χρησιμοποιηθεί για να μορφοποιήσουμε strings, όπως εδώ: +"{} can be {}".format("Strings", "interpolated") # => "Strings can be interpolated" + +# Μπορείς να επαναλάβεις τα ορίσματα του formatting για να γλιτώσεις λίγο χρονο +"{0} be nimble, {0} be quick, {0} jump over the {1}".format("Jack", "candle stick") +# => "Jack be nimble, Jack be quick, Jack jump over the candle stick" + +# Μπορείς να χρησιμοποιήσεις keywords αν βαριέσαι το μέτρημα. +"{name} wants to eat {food}".format(name="Bob", food="lasagna") # => "Bob wants to eat lasagna" + +# Αν ο κώδικας Python 3 που γράφεις πρόκειται να τρέξει και με python 2.5 ή παλιότερη +# μπορείς επίσης να χρησιμοποιήσεις το παλιό τρόπο για formatting: +"%s can be %s the %s way" % ("Strings", "interpolated", "old") # => "Strings can be interpolated the old way" + +# Μπορείς επίσης να μορφοποιήσεις χρησιμοποιώντας τα f-strings / formatted string literals (σε Python 3.6+) +name = "Reiko" +f"She said her name is {name}." # => "She said her name is Reiko" +# Μπορείς βασικά να βάλεις οποιαδήποτε έκφραση Python στα άγκιστρα και θα εμφανιστεί στο string. +f"{name} is {len(name)} characters long." + + +# το None είναι ένα αντικείμενο (object) +None # => None + +# Μη χρησιμοποιείτε το σύμβολο ισότητας "==" για να συγκρίνετε αντικείμενα με το None +# Χρησιμοποιείτε το "is". Αυτό ελέγχει για ισότητα της ταυτότητας του αντικειμένου. +"etc" is None # => False +None is None # => True + +# Τα None, 0, και τα κενά strings/lists/dicts/tuples αποτιμούνται στην τιμή False +# All other values are True +bool(0) # => False +bool("") # => False +bool([]) # => False +bool({}) # => False +bool(()) # => False + +#################################################### +## 2. Μεταβλητές (variables) και Συλλογές (collections) +#################################################### + +# Η Python έχει μία συνάρτηση print() +print("I'm Python. Nice to meet you!") # => I'm Python. Nice to meet you! + +# By default, η συνάρτηση print() τυπώνει και ένα χαρακτήρα αλλαγής γραμμμής στο τέλος +# Χρησιμοποιείτε το προαιρετικό όρισμο end για να τυπώνει οτιδήποτε άλλο +print("Hello, World", end="!") # => Hello, World! + +# Απλός τρόπος για να πάρουμε δεδομένα εισόδου από το console +input_string_var = input("Enter some data: ") # επιστρέφει τα δεδομένα ως string +# Σημ.: Στις προηγούμενες εκδόσεις της Python, η μέθοδος input() ονομαζόταν raw_input() + +# Δεν υπάρχουν δηλώσεις, μόνο αναθέσεις τιμών. +# Η σύμβαση είναι να χρησιμοποιούμε μικρά γράμματα με κάτω παύλες +some_var = 5 +some_var # => 5 + +# Η πρόσβαση σε μεταβλητή που δεν έχει λάβει τιμή είναι εξαίρεση +# Δες τον Έλεγχο Ροής για να μάθεις περισσότερα για το χειρισμό εξαιρέσεων +some_unknown_var # Προκαλέι ένα NameError + +# Η παρακάτω έκφραση μπορεί να χρησιμποιηθεί ισοδύναμα με τον τελεστή '?' της C +"yahoo!" if 3 > 2 else 2 # => "yahoo!" + +# Οι λίστες κρατούν ακολουθίς +li = [] +# Μπορείς να αρχίσεις με μία προ-γεμισμένη λίστα +other_li = [4, 5, 6] + +# Και να βάλεις πράγματα στο τέλος με την μέθοδο append +li.append(1) # η li τώρα είναι [1] +li.append(2) # η li τώρα είναι [1, 2] +li.append(4) # η li τώρα είναι [1, 2, 4] +li.append(3) # η li τώρα είναι [1, 2, 4, 3] +# Αφαιρούμε από το τέλος με την μέθοδο pop +li.pop() # => 3 και η li γίνεται [1, 2, 4] +# Ας βάλουμε το 3 πίσω στη θέση του +li.append(3) # η li γίνεται πάλι [1, 2, 4, 3]. + +# Προσπελαύνουμε τις λίστες όπως τους πίνακες σε άλλες γλώσσες +li[0] # => 1 +# Το τελευταίο στοιχείο... +li[-1] # => 3 + +# Όταν βγαίνουμε εκτός ορίων της λίστας προκαλείται IndexError +li[4] # προκαλεί IndexError + +# Μπορείς να δεις ranges μιας λίστας με το slice syntax ':' +# Ο δείκτης εκίνησης περιλαμβάνεται στο διάστημα, ο δείκτης τερματισμού όχι +# (είναι ανοικτό/κλειστό διάστημα για τους φίλους των μαθηματικών) +li[1:3] # => [2, 4] +# Αγνόησε την αρχή και επίστρεψε τη λίστα +li[2:] # => [4, 3] +# Αγνόησε το τέλος και επίστρεψε τη λίστα +li[:3] # => [1, 2, 4] +# Διάλεξε κάθε δεύτερο στοιχείο +li[::2] # =>[1, 4] +# Επίστρεψε ένα reversed αντίγραφο της λίστας +li[::-1] # => [3, 4, 2, 1] +# Χρησιμοποιείστε οποιαδήποτε συνδυασμό αυτών για να φτιάξετε πιο προχωρημένα slices +# li[start:end:step] + +# Φτιάξε ένα αντίγραφο της λίστας χρησιμοποιώντας slices +li2 = li[:] # => li2 = [1, 2, 4, 3] αλλά το (li2 is li) επιστρέφει False + +# Αφαίρεσε οποιοδήποτε στοιχείο από λίστα με την εντολή "del" +del li[2] # η li γίνεται [1, 2, 3] + +# Αφαιρούμε το πρώτο στιγμυότυπο μιας τιμής +li.remove(2) # η li γίνεται [1, 3] +li.remove(2) # Προκαλεί ένα ValueError καθώς το 2 δεν βρίσκεται στη λίστα. + +# Εισαγωγή ενός στοιχείου σε συγκεκριμένη θέση +li.insert(1, 2) # η li γίνεται πάλι [1, 2, 3] + +# Βρες το index (δείκτη) του πρώτου στοιχείου με τιμή ίση με το όρισμα +li.index(2) # => 1 +li.index(4) # Προκαλεί ValueError καθώς το 4 δεν βρίσκεται στη λίστα + +# Μπορείς να προσθέτεις λίστες +# Σημ.: οι τιμές των li, other_li δεν αλλάζουν. +li + other_li # => [1, 2, 3, 4, 5, 6] + +# Σύντμιση λιστών με τη μέθοδο "extend()" +li.extend(other_li) # Τώρα η li είναι [1, 2, 3, 4, 5, 6] + +# Ελεγχος της ύπαρξης στοιχείου σε λίστα με το "in" +1 in li # => True + +# Εξατάζουμε το μήκος με "len()" +len(li) # => 6 + + +# Τα Tuples είναι σαν τις λίστες αλλά είναι αμετάβλητα (immutable). +tup = (1, 2, 3) +tup[0] # => 1 +tup[0] = 3 # Προκαλεί TypeError + +# Σημειώστε ότι ένα tuple μήκους 1 πρέπει να έχει ένα κόμμα μετά το τελευταίο στοιχείο +# αλλά τα tuples άλλων μηκών, ακόμα και μηδενικού μήκους, δεν χρειάζονται κόμμα. +type((1)) # => +type((1,)) # => +type(()) # => + +# Μπορείς να εφαρμόσεις τις περισσότερες μεθόδους των λιστών και στα tuples +len(tup) # => 3 +tup + (4, 5, 6) # => (1, 2, 3, 4, 5, 6) +tup[:2] # => (1, 2) +2 in tup # => True + +# Μπορείς να κάνεις unpack/"ξεπακετάρεις" tuples σε μεταβλητές +a, b, c = (1, 2, 3) # a == 1, b == 2 και c == 3 +# Μπορείς επίσης να επεκτείνεις το unpacking +a, *b, c = (1, 2, 3, 4) # a == 1, b == [2, 3] και c == 4 +# Τα Tuples δημιουργούνται by deafult αν δεν βάλεις παρενθέσεις +d, e, f = 4, 5, 6 # το tuple 4, 5, 6 "ξεπακετάρεται" στις μεταβλητές d, e και f +# αντίστοιχα έτσι ώστε να γίνεται d = 4, e = 5 and f = 6 +# Δείτε πόσο εύκολα μπορούμε να εναλλάσουμε δύο τιμές +e, d = d, e # το d παίρνει την τιμή 5 και το e παίρνει την τιμή 4 + + +# Τα λεξικά (Dictionaries) αποθηκεύουν απεικονίσεις από κλειδιά σε τιμές +empty_dict = {} +# Εδώ έχουμε ένα προ-γεμισμένο dictionary +filled_dict = {"one": 1, "two": 2, "three": 3} + +# Σημ. ότι τα κλειδιά για τα dictionaries πρέπει να είναι αμετάβλητοι τύποι +# (immutable) αυτό γίνετια για να διασφαλίσουμε ότι τα κλειδιά μπορούν να +# μετατρέπονται σε σταθερές τιμές κατακερματισμού (hash values) για γρήγορη εύρεση. +# Μερικοί αμετάβλητοι τύποι είναι τα ints, floats, strings, tuples. +invalid_dict = {[1,2,3]: "123"} # => Προκαλεί TypeError: unhashable type: 'list' +valid_dict = {(1,2,3):[1,2,3]} # Οι τιμές όμως μπορούν να έχουν οποιοδήποτε τύπο. + +# Βρίσκουμε τιμές με [] +filled_dict["one"] # => 1 + +# Μπορείς να πάρεις όλα τα κλειδιά με τη μέθοδο "keys()". +# Πρέπει να "τυλίξουμε" την κλήση με list() για να το μετατρέψουμε σε λίστα +# Θα μιλήσουμε για αυτά αργότερα. Σημ. - σε εκδόσεις Python < 3.7, η σειρά που +# εμφανίζονται τα κλειδιά δεν είναι εγγυημένη. Τα αποτελέσματά σας ίσως να μην +# είναι ακριβώς ίδια με τα παρακάτω. Στην έκδοση 3.7 πάντως, τα αντικείμενα του +# λεξικού διατηρούν τη σειρά με την οποία εισήχθησαν στο dictionary +list(filled_dict.keys()) # => ["three", "two", "one"] σε Python <3.7 +list(filled_dict.keys()) # => ["one", "two", "three"] σε Python 3.7+ + +# Παίρνουμε όλες τις τιμές ενός iterable με τη μέθοδο "values()". Και πάλι +# χρειάζεται να το περιτυλίξουμε σε list() +# Σημ. - όπως παραπάνω σχετικά με τη σειρά των keys +list(filled_dict.values()) # => [3, 2, 1] in Python <3.7 +list(filled_dict.values()) # => [1, 2, 3] in Python 3.7+ + +# Έλεγχος της ύπαρξης κλειδιών σε ένα dictionary με το "in" +"one" in filled_dict # => True +1 in filled_dict # => False + +# Αν ψάξεις την τιμή ανύπαρκτου κλειδιού προκαλείται KeyError +filled_dict["four"] # KeyError + +# Χρησιμοποιούμε τη μέθοδο "get()" για να αποφύγουμε το KeyError +filled_dict.get("one") # => 1 +filled_dict.get("four") # => None +# στο δεύτερο argument της get() μπορούμε να βάλουμε μία τιμή που πρέπει να +# επιστρέψει αν δεν υπάρχει το key που ψάχνουμε +filled_dict.get("one", 4) # => 1 +filled_dict.get("four", 4) # => 4 + +# το "setdefault()" εισάγει στο dictionary μόνο αν δεν υπάρχει το κλειδί +filled_dict.setdefault("five", 5) # filled_dict["five"] γίνεται 5 +filled_dict.setdefault("five", 6) # filled_dict["five"] μένει 5 (υπαρκτό κλειδί) + +# Προσθήκη σε dictionary +filled_dict.update({"four":4}) # => {"one": 1, "two": 2, "three": 3, "four": 4} +filled_dict["four"] = 4 # β' τρόπος + +# Αφαίρεση κλειδιών από dictionary με del +del filled_dict["one"] # Αφαιρεί το κλειδί "one" από το filled_dict + +# Από την Python 3.5 μπορείς να χρησιμοποιήσεις και πρόσθετες επιλογές για unpacking +{'a': 1, **{'b': 2}} # => {'a': 1, 'b': 2} +{'a': 1, **{'a': 2}} # => {'a': 2} + + + +# τα Sets -όπως όλοι περιμένουμε- αποθηκεύουν σύνολα +empty_set = set() +# Αρχικοποιούμε ένα set με μερικές τιμές. Ναι, μοιάζει λίγο με dictionary, Sorry. +some_set = {1, 1, 2, 2, 3, 4} # some_set is now {1, 2, 3, 4} + +# Παρομοίως με τα κλειδιά του dictionary, τα στοιχεία ενός συνόλου πρέπει να είναι +# αμετάβλητα (immutable) +invalid_set = {[1], 1} # => Προκαλεί TypeError: unhashable type: 'list' +valid_set = {(1,), 1} + +# Προσθέτουμε άλλο ένα στοιχείο στο σύνολο +filled_set = some_set +filled_set.add(5) # το filled_set είναι τώρα {1, 2, 3, 4, 5} +# Τα σύνολα δεν έχουν διπλοτυπα αντικείμενα +filled_set.add(5) # το σύνολο παραμένει ίδιο {1, 2, 3, 4, 5} + +# το & κάνει την τομή δύο συνόλων. +other_set = {3, 4, 5, 6} +filled_set & other_set # => {3, 4, 5} + +# και το | την ένωση +filled_set | other_set # => {1, 2, 3, 4, 5, 6} + +# Η διαφορά συνόλων με το - +{1, 2, 3, 4} - {2, 3, 5} # => {1, 4} + +# Το ^ επιστρέφει τη συμμετρική διαφορά +{1, 2, 3, 4} ^ {2, 3, 5} # => {1, 4, 5} + +# Ελεγχος για το αν το δεξιά σύνολο είναι υπερσύνολο του δεξιού +{1, 2} >= {1, 2, 3} # => False + +# Ελεγχος για το αν το δεξιά σύνολο είναι υποσύνολο του δεξιού +{1, 2} <= {1, 2, 3} # => True + +# με το in κάνουμε έλεγχο ύπαρξης στοιχείο σε σετ +2 in filled_set # => True +10 in filled_set # => False + + + +#################################################### +## 3. Έλεγχος Ροής και Iterables +#################################################### + +# Φτιάχνουμε μία μεταβλητή +some_var = 5 + +# Εδώ έχουμε ένα if statement. Η στοίχιση είναι σημαντική στην Python! +# Η σύμβαση είναι να χρησιμοποιούμε 4 κενά, όχι tabs. +# Το παρακάτω τυπώνει "some_var is smaller than 10" +if some_var > 10: + print("some_var is totally bigger than 10.") +elif some_var < 10: # το (else if) -> elif μέρος είναι προαιρετικό. + print("some_var is smaller than 10.") +else: # και το else είναι προαιρετικό. + print("some_var is indeed 10.") + + +""" +τα for loops τρέχουν πάνω σε lists +το παρακάτω τυπώνει: + dog is a mammal + cat is a mammal + mouse is a mammal +""" +for animal in ["dog", "cat", "mouse"]: + # You can use format() to interpolate formatted strings + print("{} is a mammal".format(animal)) + +""" +το "range(number)" επιστρέφει ένα iterable με αριθμούς +από το μηδέν μέχρι τον δωσμένο αριθμό number (κλειστό/ανοικτό διάστημα) +Το παρακάτω τυπώνει: + 0 + 1 + 2 + 3 +""" +for i in range(4): + print(i) + +""" +το "range(lower, upper)" επιστρέφει ένα iterable με αριθμούς +από το lower εώς το upper (κλειστό/ανοικτό διάστημα) +το παρακάτω τυπώνει: + 4 + 5 + 6 + 7 +""" +for i in range(4, 8): + print(i) + +""" +το "range(lower, upper, step)" επιστρέφει ένα iterable με αριθμούς +από το lower μέχρι το upper, με βήμα step +αν δεν δώσουμε τιμή βήματος, το default βήμα είναι 1. +το παρακάτω τυπώνει: + 4 + 6 +""" +for i in range(4, 8, 2): + print(i) +""" + +τα While loops τρέχουν μέχρι μία συνθήκη να γίνει ψευδής. +το παρακάτω τυπώνει: + 0 + 1 + 2 + 3 +""" +x = 0 +while x < 4: + print(x) + x += 1 # Shorthand for x = x + 1 + +# Χειριζόμαστε εξαιρέσεις με ένα try/except block +try: + # Χρησιμοποιούμε το "raise" για να πετάξουμε ένα error + raise IndexError("This is an index error") +except IndexError as e: + pass # το Pass δεν κάνει τίποτα. Συνήθως κάνουμε ανάκτηση. +except (TypeError, NameError): + pass # Μπορούμε να χειριζόμαστε πολλές εξαιρέσεις μαζί, αν χρειαστεί +else: # Προαιρετικό στο try/except block. Πρέπει να ακολουθεί όλα τα except blocks + print("All good!") # τρέχει μόνο αν ο κώδικας στο try δεν προκαλεί εξαιρέσεις +finally: # Εκτελείται ό,τι και να γίνει + print("We can clean up resources here") + +# Αντί για try/finally για να καθαρίσουμε τους πόρους, μπορούμε να χρησιμοποιούμε το +# with expression as target: + pass to cleanup resources you can use a with statement +with open("myfile.txt") as f: + for line in f: + print(line) + +# Η Python προσφέρει μία θεμελιώδη αφαίρεση (abstraction) που λέγεται Iterable. +# iterable είναι ένα αντικείμενο που μπορεί να χρησιμοποιηθεί ως ακολουθία. +# Το αντικείμενο που επιστρέφει η συνάρτηση range, είναι ένα iterable. + +filled_dict = {"one": 1, "two": 2, "three": 3} +our_iterable = filled_dict.keys() +print(our_iterable) # => dict_keys(['one', 'two', 'three']). +# Αυτό είναι ένα αντικείμενο που υλοποιεί την iterable διεπαφή μας. + +# μπορούμε να τρέχουμε loops πάνω του. +for i in our_iterable: + print(i) # Prints one, two, three + +# Ωστόσο δεν μπορούμε να προσπελάσουμε τα στοιχεία του με index. +our_iterable[1] # προκαλεί a TypeError + +# Ένα iterable είναι ένα αντικείμενο που ξέρει πώς να δημιουργήσει έναν iterator. +our_iterator = iter(our_iterable) + +# Ο iterator μας είναι ένα αντικείμενο που μπορεί να θυμάται την κατάσταση όπως το διατρέχουμε. +# Παίρνουμε το επόμενο αντικείμενο με το "next()" +next(our_iterator) # => "one" + +# Διατηρεί την κατάσταση καθώς επαναλαμβάνουμε. +next(our_iterator) # => "two" +next(our_iterator) # => "three" + +# Όταν ο iterator έχει επιστρέψει όλα τα δεδομένα του, προκαλεί ένα μια εξαίρεση StopIteration. +next(our_iterator) # προκαλεί StopIteration + +# Μπορείς να πάρεις όλα τα αντικείμενα ενός iteratior καλώντας list() πάνω του. +list(filled_dict.keys()) # => Επιστρέφει ["one", "two", "three"] + + +#################################################### +## 4. Συναρτήσεις +#################################################### + +# Χρησιμποιούμε το "def" για να ορίσουμε νέες συναρτήσεις +def add(x, y): + print("x is {} and y is {}".format(x, y)) + return x + y # επιστρέφει τιμές με την εντολή return + +# Καλούμε συναρτήσεις με παραμέτρους +add(5, 6) # => τυπώνει "x is 5 and y is 6" και επιστρέφει 11 + +# Ένας άλλος τρόπος να καλέσεις συνάρτησει είναι με keyword arguments (ορίσματα λέξεις-κλειδιά) +add(y=6, x=5) # τα Keyword arguments μπορούν να δωθούν με οποιαδήποτε σειρά. + +# Μπορείς να ορίσεις συναρτήσεις που δέχονται μεταβλητό πλήθος ορισμάτων +def varargs(*args): + return args + +varargs(1, 2, 3) # => (1, 2, 3) + +# Μπορούμε να ορίσουμε και συναρτήσεις που δέχονται μεταβλητό πλήθος keyword arguments +def keyword_args(**kwargs): + return kwargs + +# Για να δούμε τι γίνεται αν την καλέσουμε +keyword_args(big="foot", loch="ness") # => {"big": "foot", "loch": "ness"} + + +# Μπορείς να κάνεις και τα δύο ταυτόχρονα αν θες +def all_the_args(*args, **kwargs): + print(args) + print(kwargs) +""" +all_the_args(1, 2, a=3, b=4) τυπώνει: + (1, 2) + {"a": 3, "b": 4} +""" + +# Όταν καλείς συναρτήσεις μπορείς να κάνεις και το αντίστροφο από args/kwargs! +# Χρησιμοποίησε το * για να επεκτείνεις tuples και χρησιμοποίησε το ** για να επεκτείλεις kwargs +args = (1, 2, 3, 4) +kwargs = {"a": 3, "b": 4} +all_the_args(*args) # ισοδύναμο με all_the_args(1, 2, 3, 4) +all_the_args(**kwargs) # ισοδύναμο με all_the_args(a=3, b=4) +all_the_args(*args, **kwargs) # ισοδύναμο με all_the_args(1, 2, 3, 4, a=3, b=4) + +# Επιστρέφουμε πλειάδα τιμών (με tuple assignments) +def swap(x, y): + return y, x # Επιστρέφει πολλές τιμές ως tuple χωρίς την παρένθεση + # (Σημ.: οι παρενθέσεις έχουν παραλειφθεί αλλά μπορούν να γραφούν) + +x = 1 +y = 2 +x, y = swap(x, y) # => x = 2, y = 1 +# (x, y) = swap(x,y) # Ξανά, οι παρενθέσεις έχουν παραληφθεί αλλά μπορούν να γραφούν + +# Εμβέλεια συναρτήσεων +x = 5 + +def set_x(num): + # Η τοπική μεταβλητή x δεν είναι η ίδια με την global μεταβλητή x + x = num # => 43 + print(x) # => 43 + +def set_global_x(num): + global x + print(x) # => 5 + x = num # η global μεταβλητή x τώρα είναι 6 + print(x) # => 6 + +set_x(43) +set_global_x(6) + + +# Η Python έχει πρώτης τάξης συναρτήσεις +def create_adder(x): + def adder(y): + return x + y + return adder + +add_10 = create_adder(10) +add_10(3) # => 13 + +# Αλλά έχει και anonymous συναρτήσεις. +(lambda x: x > 2)(3) # => True +(lambda x, y: x ** 2 + y ** 2)(2, 1) # => 5 + +# Υπάρχουν ενσωματωμένες συναρτήσεις μεγαλύτερης τάξης +list(map(add_10, [1, 2, 3])) # => [11, 12, 13] +list(map(max, [1, 2, 3], [4, 2, 1])) # => [4, 2, 3] + +list(filter(lambda x: x > 5, [3, 4, 5, 6, 7])) # => [6, 7] + +# Μπορούμε να χρησιμοποιήσουμε list comprehensions για ωραία maps και filters +# το List comprehension αποθηκεύει την έξοδο ως μία λίστα που μπορεί και η ίδια +# να είναι μια εμφωλευμένη λίστα +[add_10(i) for i in [1, 2, 3]] # => [11, 12, 13] +[x for x in [3, 4, 5, 6, 7] if x > 5] # => [6, 7] + +# Μπορείς επίσης να κατασκευάσεις set και dict comprehensions. +{x for x in 'abcddeef' if x not in 'abc'} # => {'d', 'e', 'f'} +{x: x**2 for x in range(5)} # => {0: 0, 1: 1, 2: 4, 3: 9, 4: 16} + + +#################################################### +## 5. Modules +#################################################### + +# Μπορείς να κάνεις import modules +import math +print(math.sqrt(16)) # => 4.0 + +# Μπορείς να πάρεις συγκεκριμένες συναρτήσεις από ένα module +from math import ceil, floor +print(ceil(3.7)) # => 4.0 +print(floor(3.7)) # => 3.0 + +# Μπορείς να κάνεις import όλες τις συναρτήσεις από ένα module. +# Προσοχή: δεν προτείνεται +from math import * + +# Μπορείς να δημιουργείς συντομογραφίες για τα ονόματα των modules +import math as m +math.sqrt(16) == m.sqrt(16) # => True + +# Τα Python modules είναι απλά αρχεία Python. Μπορείς να δημιουργήσεις τα δικά σου +# και να τα κάνεις import το όνομα του module είναι ίδιο με το όνομα του αρχείου + +# μπορείς να βρεις ποιες συναρτήσεις και γνωρίσματα ορίζονται στο module +import math +dir(math) + +# Αν έχεις ένα Python script με όνομα math.py στον ίδιο φάκελο με το τρέχον script +# το αρχείο math.py θα φορτωθεί και όχι το built-in Python module +# Αυτό συμβαίνει επειδή τα τοπικά αρχεία έχουν προτεραιότητα έναντι των built-in +# βιβλιοθηκών της Python + + +#################################################### +## 6. Κλάσεις - Classes +#################################################### + +# χρησιμοποιούμε το "class" statement για να δημιουργήσουμε μια κλάση +class Human: + + # Ένα γνώρισμα της κλάσης. Είναι κοινό για όλα τα στιγμιότυπα αυτής. + species = "H. sapiens" + + # Βασικός initializer, καλείται όταν δημιουργείται στιγμιότυπο της κλάσης. + # Σημ. οι διπλές κάτω παύλες πριν και μετά υποδηλώνουν αντικείμενα + # ή γνωρίσματα που χρησιμοποιούνται από την Python αλλά ζουν σε ελεγχόμενα από + # το χρήση namespaces. + # Μέθοδοι (ή αντικείμενα ή γνωρίσματα) σαν τα __init__, __str__, __repr__ κλπ + # είναι ειδικές μέθοδοι (λέγονται και dunder (double underscore) μέθοδοι) + # Δεν πρέπει να δηλώνεις δικές σου τέτοιες συναρτήσεις + def __init__(self, name): + # Εκχώρησε στο attribute name του object το όρισμα + self.name = name + + # Αρχικοποίησε την ιδιότητα + self._age = 0 + + # Μία μέθοδος στιγμιότυπου (instance method). Όλες οι μέθοδοι παίρνουν το + # "self" ως πρώτο όρισμα + def say(self, msg): + print("{name}: {message}".format(name=self.name, message=msg)) + + # Ακόμα μία instance method + def sing(self): + return 'yo... yo... microphone check... one two... one two...' + + # Μία μέθοδος κλάσεις είναι κοινή ανάμεσα σε όλα τα instances. + # Καλούνται με calling class ώς πρώτο όρισμα + @classmethod + def get_species(cls): + return cls.species + + # Μία στατική μέθοδος καλείται χωρίς αναφορά σε κλάση ή στιγμιότυπο + @staticmethod + def grunt(): + return "*grunt*" + + # Ένα property είναι ακριβώς σαν ένα getter. + # Μετατρέπει τη μέθοδο age σε ένα γνώρισμα (attribute) μόνο-για-ανάγνωση + # με το ίδιο όνομα. + # Δεν χρειάζεται να γράφουμε τετριμένους getters και setters στην Python όμως. + @property + def age(self): + return self._age + + # Αυτό επιτρέπει στο property να γίνει set + @age.setter + def age(self, age): + self._age = age + + # Αυτό επιτρέπει σε ένα property να διαγραφεί + @age.deleter + def age(self): + del self._age + + +# Όταν ο διερμηνέας της Python διαβάζει αρχείο πηγαίου κώδικα τον εκτελεί όλο. +# Αυτός ο έλεγχος του __name__ σιγουρεύει ότι αυτό το block κώδικα τρέχει μόνο +# αυτό το module είναι το κύριο πρόγραμμα (και όχι imported) +if __name__ == '__main__': + # Δημιουργούμε στιγμιότυπο κλάσης + i = Human(name="Ian") + i.say("hi") # "Ian: hi" + j = Human("Joel") + j.say("hello") # "Joel: hello" + # τα i και j είναι στιγμιότυπα του τύπου Human + + # Καλούμε τη μέθοδο της κλάσης + i.say(i.get_species()) # "Ian: H. sapiens" + # Αλλάζουμε το κοινό attribute των αντικειμένων της κλάσης + Human.species = "H. neanderthalensis" + i.say(i.get_species()) # => "Ian: H. neanderthalensis" + j.say(j.get_species()) # => "Joel: H. neanderthalensis" + + # Καλούμε τη static μέθοδο + print(Human.grunt()) # => "*grunt*" + + # Δεν μπορούμε να καλέσουμε τη στατική μέθοδο με ένα στιγμιότυπο + # επειδή το i.grunt() θα βάλει αυτόματα το self (δηλαδή το αντικείμενο i) ως όρισμα + print(i.grunt()) # => TypeError: grunt() takes 0 positional arguments but 1 was given + + # Ενημερώνουμε το property για αυτό το στγμιότυπο + i.age = 42 + # Παίρνουμε το property + i.say(i.age) # => "Ian: 42" + j.say(j.age) # => "Joel: 0" + # Διαγράφουμε το property + del i.age + # i.age # => αυτό θα προκαλούσε AttributeError + + +#################################################### +## 6.1 Κληρονομικότητα - Inheritance +#################################################### + +# Η κληρονομικότητα επιτρέπει σε νέες κλάσεις-παιδιά να οριστούν και να υιοθετήσουν +# μεθόδους και μεταβλητές από την κλάση-γονέα. + +# Χρησιμοποιώντας την κλάση Human που ορίστηκε πριν ως τη βασική κλάση (ή κλάση-γονέα) +# μπορούμε να ορίσουμε τις κλάσεις-παιδιά Superhero, που κληρονομεί μεταβλητές όπως +# "species", "name", και "age", καθώς και μεθόδους όπως "sing" και "grunt" +# από την κλάση Human, αλλά επίσης έχει τις δικές του ξεχωριστές ιδιότητες + +# Για να εκμεταλλευτείς το modularization κατά αρχείο, μπορείς να βάλεις την παραπάνω κλάση +# σε δικό της αρχείο, ας πούμε human.py + +# Για να κάνουμε import συναρτήσεις από άλλα αρχεία χρησιμοποιούμε το παρακάτω format +# from "filename-without-extension" import "function-or-class" + +from human import Human + + +# Προσδιόρισε την/τις parent class(es) ως παραμέτρους της κλάσης που ορίζεται +class Superhero(Human): + + # Αν η κλάση-παιδί πρέπει να κληρονομήσει όλους τους οεισμούς της κλάσης-γονέα + # χωρίς καμία αλλαγή, μπορείς απλά να γράψεις pass (και τίποτα άλλο) + # αλλά σε αυτή την περίπτωση είναι σχολιασμένο για να επιτρέψει τη δημιουργία + # ξεχωριστής κλάσης-παιδιού: + # pass + + # Η κλάση παιδί μπορεί να υπερφορτώσει (override) τα attributes της κλάσης από την οποία κληρονομεί + species = 'Superhuman' + + # Τα παιδιά αυτόματα, κληρονομούν τον constructo της κλάσης-γονέα + # συμπεριλαμβανομένων των ορισμάτων, αλλά μπορείς και να ορίσεις πρόσθετα ορίσματα + # ή ορισμούς και να κάνεις override τις μεθόδους, όπως τον constructor. + # Αυτός ο constructor κληρονομεί το όρισμα "name" από την κλάση Human και + # προσθέτει τα ορίσματα "superpower" και "movie": + def __init__(self, name, movie=False, + superpowers=["super strength", "bulletproofing"]): + + # πρόσθήκη επιπλέον attributes της κλάσης: + self.fictional = True + self.movie = movie + # έχετε το νου σας τις μεταβλητές (mutable) default τιμές, καθώς είναι κοινές + self.superpowers = superpowers + + # Η συνάρτηση "super" επιτρέπει την πρόσβαση στις μεθόδους της κλάσης-γονέα + # που είναι υπερφορτωμένες από το παιδί. Σε αυτή την περίπτωση τη μέθοδο __init__ + # Το παρακάτω καλεί τον constructor της κλάσης-γονέα: + super().__init__(name) + + # υπερφόρτωση της μεθόδου sing + def sing(self): + return 'Dun, dun, DUN!' + + # προσθήκη νέας μεθόδου που εφαρμόζεται σε στιγμιότυπα + def boast(self): + for power in self.superpowers: + print("I wield the power of {pow}!".format(pow=power)) + + +if __name__ == '__main__': + sup = Superhero(name="Tick") + + # Έλεγχος για το αν το στιγμιότυπο sup ανήκει στην κλάση Human + if isinstance(sup, Human): + print('I am human') + if type(sup) is Superhero: + print('I am a superhero') +# TODO: + # Παίρνουμε το Method Resolution search Order που χρησιμοποιούν οι getattr() και super() + # Αυτό το attribute είναι δυναμικό και μπορεί να ανανεωθεί + print(Superhero.__mro__) # => (, + # => , ) + + # Καλούμε μέθοδο της κλάσης-γονέα, αλλά χρησιμοποιεί το δικό της attribute + print(sup.get_species()) # => Superhuman + + # Καλεί την υπερφορτωμένη μέθοδο + print(sup.sing()) # => Dun, dun, DUN! + + # Καλεί μέθοδο από την κλάση Human + sup.say('Spoon') # => Tick: Spoon + + # Καλεί μέθοδο που υπάρχει μόνο στην κλάση Superhero + sup.boast() # => I wield the power of super strength! + # => I wield the power of bulletproofing! + + # Κληρονομημένο class attribute + sup.age = 31 + print(sup.age) # => 31 + + # Attribute που υπάρχει μόνο στην μέσα στην κλάση Superhero + print('Am I Oscar eligible? ' + str(sup.movie)) + +#################################################### +## 6.2 Πολλαπλή Κληρονομικότητα - Multiple Inheritance +#################################################### + +# Ένας ακόμη ορισμός κλάσης +# bat.py +class Bat: + + species = 'Baty' + + def __init__(self, can_fly=True): + self.fly = can_fly + + # Αυτή η κλάση έχει επίσης μία μέθοδο say + def say(self, msg): + msg = '... ... ...' + return msg + + # Και τη δική της μέθοδο sonar + def sonar(self): + return '))) ... (((' + +if __name__ == '__main__': + b = Bat() + print(b.say('hello')) + print(b.fly) + + +# Και ορίζουμε μία ακόμα κλάση που κληρονομεί από τις κλάσεις Superhero και Bat +# superhero.py +from superhero import Superhero +from bat import Bat + +# Ας πούμε αυτή την κλάση Batman +class Batman(Superhero, Bat): + + def __init__(self, *args, **kwargs): + # Τυπικά γα να κληρονομήουμε attributes πρέπει να καλέσουμε τη super: + # super(Batman, self).__init__(*args, **kwargs) + # Ωστόσο έχουμε να κάνουμε με πολλαπλή κληρονομικότητα εδώ, και το super() + # δουλεύει μόνο με την αμέσως ανώτερη κλάση στην ιεραρχία. + # Οπότε, καλούμε ρητά την __init__ για όλους τους πρόγονους + # Η χρήση των *args και **kwargs επιτρέπει έναν καθαρό τρόπο για να περνάμε ορίσματα + # με κάθε κλάση-γονέα να "βγάζει μία φλούδα από το κρεμμύδι". + Superhero.__init__(self, 'anonymous', movie=True, + superpowers=['Wealthy'], *args, **kwargs) + Bat.__init__(self, *args, can_fly=False, **kwargs) + # υπερφορτώνουμε την τιμή του γνωρίσματος name + self.name = 'Sad Affleck' + + def sing(self): + return 'nan nan nan nan nan batman!' + + +if __name__ == '__main__': + sup = Batman() + + # + # Λάβε το Method Resolution search Order που χρησιμοποιείται από το getattr() και το super(). + # Αυτό το attribute είναι δυναμικό και μπορεί να ενημερωθεί + print(Batman.__mro__) # => (, + # => , + # => , + # => , ) + + # Καλεί την μέθοδο της κλάσης-πατέρα αλλά χρησιμοποιεί το attribute της δικής του κλάσης + print(sup.get_species()) # => Superhuman + + # Καλεί την υπερφορτωμένη μέθοδο + print(sup.sing()) # => nan nan nan nan nan batman! + + # Καλεί μέθοδο από την κλάση Human, επειδή μετράει η σειρά της κληρονομιάς + sup.say('I agree') # => Sad Affleck: I agree + + # Καλεί μέθοδο που ανήκει μόνο στον δεύτερο πρόγονο + print(sup.sonar()) # => ))) ... ((( + + # Attribute της κληρονομημένης κλάσης + sup.age = 100 + print(sup.age) # => 100 + + # Κληρονομούμενο attribute από τον δεύτερο πρόγονο του οποίου η default τιμή + # έχει υπερφορτωθεί. + print('Can I fly? ' + str(sup.fly)) # => Can I fly? False + + + +#################################################### +## 7. Προχωρημένα +#################################################### + +# Με τους Generators μπορείς να γράψεις τεμπέλικο κώδικα. +def double_numbers(iterable): + for i in iterable: + yield i + i +# Οι Generators είναι αποδοτικοί από άποψη μνήμης επειδή φορτώνουν μόνο τα δεδομένα +# που είναι αναγκαία για να επεξεργαστούμε την επόμενη τιμή του iterable. +# Αυτό μας επιτρέπει να κάνουμε πράξεις σε τιμές που υπό άλλες συνθήκες θα ήταν +# απαγορευτικά μεγάλες. +for i in double_numbers(range(1, 900000000)): # το `range` είναι ένας generator. + print(i) + if i >= 30: + break + +# Όπως μπορείς να δημιουργήσεις list comprehension, έτσι μπορείς να δημιουργήσεις και +# generator comprehensions +values = (-x for x in [1,2,3,4,5]) +for x in values: + print(x) # τυπώνει -1 -2 -3 -4 -5 στο console/terminal + +# Μπορείς επίσης να μετατρέψεις ένα generator comprehension απευθείας σε λίστα. +values = (-x for x in [1,2,3,4,5]) +gen_to_list = list(values) +print(gen_to_list) # => [-1, -2, -3, -4, -5] + + +# Decorators +# σε αυτό το παράδειγμα το `beg` τυλίγει το `say`. Αν το say_please είναι True τότε +# θα αλλάξει το μήνυμα που επιστρέφεται. +from functools import wraps + + +def beg(target_function): + @wraps(target_function) + def wrapper(*args, **kwargs): + msg, say_please = target_function(*args, **kwargs) + if say_please: + return "{} {}".format(msg, "Please! I am poor :(") + return msg + + return wrapper + + +@beg +def say(say_please=False): + msg = "Can you buy me a beer?" + return msg, say_please + + +print(say()) # Can you buy me a beer? +print(say(say_please=True)) # Can you buy me a beer? Please! I am poor :( +``` + +## Έτοιμοι για περισσότερα? + +### Δωρεάν Online + +* [Automate the Boring Stuff with Python](https://automatetheboringstuff.com) +* [Ideas for Python Projects](http://pythonpracticeprojects.com) +* [The Official Docs](http://docs.python.org/3/) +* [Hitchhiker's Guide to Python](http://docs.python-guide.org/en/latest/) +* [Python Course](http://www.python-course.eu/index.php) +* [First Steps With Python](https://realpython.com/learn/python-first-steps/) +* [A curated list of awesome Python frameworks, libraries and software](https://github.com/vinta/awesome-python) +* [30 Python Language Features and Tricks You May Not Know About](http://sahandsaba.com/thirty-python-language-features-and-tricks-you-may-not-know.html) +* [Official Style Guide for Python](https://www.python.org/dev/peps/pep-0008/) +* [Python 3 Computer Science Circles](http://cscircles.cemc.uwaterloo.ca/) +* [Dive Into Python 3](http://www.diveintopython3.net/index.html) +* [A Crash Course in Python for Scientists](http://nbviewer.jupyter.org/gist/anonymous/5924718) -- cgit v1.2.3 From 05872fc6316d7c6d8cc821a7bb4a74b306d9ce5f Mon Sep 17 00:00:00 2001 From: Vy Hong Date: Tue, 22 Oct 2019 08:35:34 -0700 Subject: Update comment in Java doWhile loop --- java.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/java.html.markdown b/java.html.markdown index ca0b04c2..aa8923ab 100644 --- a/java.html.markdown +++ b/java.html.markdown @@ -381,7 +381,7 @@ public class LearnJava { do { System.out.println(fooDoWhile); // Increment the counter - // Iterated 99 times, fooDoWhile 0->99 + // Iterated 100 times, fooDoWhile 0->99 fooDoWhile++; } while(fooDoWhile < 100); System.out.println("fooDoWhile Value: " + fooDoWhile); -- cgit v1.2.3 From 18b796972639303e472c8f5d1575061d8c8da2ac Mon Sep 17 00:00:00 2001 From: Flo Date: Tue, 22 Oct 2019 23:11:23 +0100 Subject: add go build tags --- go.html.markdown | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/go.html.markdown b/go.html.markdown index ae99535b..4fc155b5 100644 --- a/go.html.markdown +++ b/go.html.markdown @@ -30,6 +30,12 @@ Go comes with a good standard library and a sizeable community. /* Multi- line comment */ + /* A build tag is a line comment starting with // +build + and can be execute by go build -tags="foo bar" command. + Build tags are placed before the package clause near or at the top of the file + followed by a blank line or other line comments. */ +// +build prod, dev, test + // A package clause starts every source file. // Main is a special name declaring an executable rather than a library. package main -- cgit v1.2.3 From 11413f734b6792ece40a80833bee24608e316731 Mon Sep 17 00:00:00 2001 From: Jack Smith Date: Tue, 22 Oct 2019 21:31:02 -0500 Subject: [hdl/en] Add Hardware Description Language Documentation --- hdl.html.markdown | 230 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 230 insertions(+) create mode 100644 hdl.html.markdown diff --git a/hdl.html.markdown b/hdl.html.markdown new file mode 100644 index 00000000..02ab1c41 --- /dev/null +++ b/hdl.html.markdown @@ -0,0 +1,230 @@ +--- +language: hdl +filename: learnhdl.hdl +contributors: + - ["Jack Smith", "https://github.com/JSmithTech2019"] +--- + +HDL (hardware description language) is a specialized language used to describe the structure/behavior of real world circuits. + +It is used by circuit designers to simulate circuits and logic prior to wiring and fabricating a hardware circuit. + +HDL allows circuit designers to simulate circuits at a high level without being connected to specific components. + +## Basic building blocks & introduction to the language--- +This programming language is built by simulating hardware chips and wiring. Normal programming functions are replaced with specialized chips that are added to the current wiring desing. Every base chip must be written as it's own file and imported to be used in the current chip, though they may be reused as often as desired. + +```verilog +// Single line comments start with two forward slashes. + +/* + * Multiline comments can be written using '/*' and 'star/'. + * These are often used as comments. + * + * Note that they cannot be nested and will end at the first 'star/'. + */ + +//////////////////////////////////////////////////// +// 1. Chips & Components +//////////////////////////////////////////////////// +/* + * Unlike other languages HDL creates an individual chip (function) per file + * These are defined with a name, input arguments, output arguments + * and finally the parts/logic of that specific chip. + */ + +// Note CHIP is capitalized, the chip name does not need to be. +CHIP Ex { + IN a, // Single bit (0 or 1) variable. + c[16]; // 16 bit variable bus of single bit values. + + OUT out[16], // 16 bit variable bus output. + carry; // Single bit output variable + + PARTS: + // The functional components of the chip. +} + +// Lines are ended with semicolons but can be continued using commas. The +// whitespace is ignored. + + + +//////////////////////////////////////////////////// +// 2. Inputs, Outputs, & Variables +//////////////////////////////////////////////////// +/* + * Variables and IO are treated as pins/wires and can carry a single bit + * of data (0 or 1). + */ + +// Hardware works on low level 0's and 1's, in order to use a constant +// high or low we use the terms true and false. +a=false; // This is a 0 value. +b=true; // This is a 1 value. + +// Inputs and outputs can be defined as single bits +IN a, b; // Creates two single bit inputs + +// They can also be defined as busses act as arrays where each +// index can contain a single bit value. +OUT c[16]; // Creates a 16 bit output array. + +// Bussed values can be accessed using brackets +a[0] // The first indexed value in the bus a. +a[0..3] // The first 4 values in the a bus. +// Values can also be passed in entirety. For example if the function +// foo() takes an 8 bit input bus and outputs a 2 bit bus: +foo(in=a[0..7], out=c); // C is now a 2 bit internal bus + + +// Note that internally defined busses cannot be subbussed! +// To access these elements, output or input them seperately: +foo(in[0]=false, in[1..7]=a[0..6], out[0]=out1, out[1]=out2); +// out1 and out2 can then be passed into other circuits within the design. + + + +//////////////////////////////////////////////////// +// Combining Subsystems +//////////////////////////////////////////////////// +/* + * HDL relies heavily on using smaller "building block" chips to then be + * added into larger and more complex designs. Creating the smaller components + * and then adding them to the larger circuit allows for fewer lines of code + * as well as reduction in total rewriting of code. + */ + +// We are writing the function AND that checks if inputs I and K are both one. +// To implement this chip we will use the built in NAND gate as well as design +// a custom NOT gate to invert a single input. + +// First we construct the Negation (not) chip. We will use the logically +// complete gate NAND that is built in for this task. +CHIP Not { + IN i; // Not gates only take one single bit input. + OUT o; // The negated value of a. + + PARTS: + // Add the input to the built in chip, which then sends output to the NOT + // output. This effectively negates the given value. + Nand(a=i, b=i, out=o); +} + +// By using the built in NAND gate we were able to construct a NOT gate +// that works like a real world hardware logic chip. Now we must construct +// the AND gate using these two gate primitives. + +// We define a two input, single output AND gate: +CHIP And { + IN i, k; // Two single bit inputs. + OUT o; // One single bit output. + + PARTS: + // Insert I and K into the nand gate and store the output in an internal + // wire called notOut. + Nand(a=i,b=b,out=notOut); + + // Use the not gate we constructed to invert notOut and send to the AND + // output. + Not(in=notOut,out=o); +} + +// Easy! Now we can use Nand, And, and Not gates in higher level circuits. +// Many of these low level components are built in to HDL but any chip can +// be written as a submodule and used in larger designs. +``` + +## Test Files +When working with the nand2tetris hardware simulator chips written using HDL will +then be processed against test and comparison files to test functionality of the +simulated chip versus the expected output. To do this a test file will be loaded +into the hardware simulator and run against the simulated hardware. + +```verilog +// First the chip the test file is written for is loaded +load .hdl + +// We set the output file for the simulated chip output as well as the comparison +// file that it will be tested against. We also specify what the output is expected +// to look like. In this case there will be two output columns, each will be buffered +// by a single space on either side and 4 binary values in the center of each column. +output-file .out, +compare-to .cmp, +output-list in%B1.4.1 out%B1.4.1; + +// Then we set initial values for inputs to the chip. For example +set enable1 1, // set input enable1 to 1 +set enable2 0, // set input enable2 to 0 + +// The clock is also controlled in the test file using tick and tock. Tick is a positive +// pulse and tock takes the clock back to 0. Clock cycles can be run multiple times in +// a row with no other changes to inputs or outputs. +tick, +tock, + +// Finally we output the first expected value (from the test file) which is then compared +// with the first line of real output from our HDL circuit. This output +// can be viewed in the .out file. +output; + +// An example of , a chip that takes in a 4 bit value as input and adds 1 to +// that value could have the following as test code: + +// Set the input value to 0000, clock pulse, compare output from cmp file to actual out. +set in %B0000, +tick, +tock, +output; + +// Set the input value to 0110, clock pulse, compare output from cmp file to actual out. +set in %B0110, +tick, +tock, +output; + +// The expected output for case 1 should be 0001 and case 2 expects 0111, lets learn +// a little more about comparison files before finalizing our lesson. +``` + +## Comparison Files +Now lets take a look at comparison files, the files that hold what the test file compares +with the actual output of an HDL chip in the hardware simulator! + +```verilog +// Like the example above, the structure of the comparison file would look +// something like this +| in | out | +| 0000 | 0001 | +| 0110 | 0111 | + +// Notice how the input values specified in the test case are equivalent to the +// `in` column of the comparison file, and that the space buffer is 1 on either side. + +// If the output from the HDL code we not this, such as the output below, then the +// test will fail and the user will know that the simulated chip is not correctly designed. +| in | out | +| 0000 | 0001 | +| 0110 | 0110 | // Error! The chip did not add 1 here, something went wrong. + + +``` + +This is incredibly useful as it allows designers to simulate chip logic prior to +fabricating real life hardware and identify problems in their designs. Be warned that +errors in the test or comparison files can lead to both false positives and also +the more damaging false negatives so ensure that the logic is sound behind the test +creation. + + +Good luck and happy coding! + +## Resources + +* [From Nand To Tetris](https://www.nand2tetris.org) + +## Further Reading + +* [Hardware Description Language](https://en.wikipedia.org/wiki/Hardware_description_language) + +* [HDL Programming Fundamentals](https://www.electronicdesign.com/products/hdl-programming-fundamentals) \ No newline at end of file -- cgit v1.2.3 From 0650f7b0183d4a5aa1ec905fd47de8c96adecdc0 Mon Sep 17 00:00:00 2001 From: Jack Smith Date: Tue, 22 Oct 2019 21:39:03 -0500 Subject: [hdl/en] Add Hardware Description Language Documentation --- hdl.html.markdown | 33 +++++++++++++++++---------------- 1 file changed, 17 insertions(+), 16 deletions(-) diff --git a/hdl.html.markdown b/hdl.html.markdown index 02ab1c41..cad07817 100644 --- a/hdl.html.markdown +++ b/hdl.html.markdown @@ -146,9 +146,10 @@ into the hardware simulator and run against the simulated hardware. load .hdl // We set the output file for the simulated chip output as well as the comparison -// file that it will be tested against. We also specify what the output is expected -// to look like. In this case there will be two output columns, each will be buffered -// by a single space on either side and 4 binary values in the center of each column. +// file that it will be tested against. We also specify what the output is +// expected to look like. In this case there will be two output columns, each +// will be buffered by a single space on either side and 4 binary values in +// the center of each column. output-file .out, compare-to .cmp, output-list in%B1.4.1 out%B1.4.1; @@ -157,19 +158,19 @@ output-list in%B1.4.1 out%B1.4.1; set enable1 1, // set input enable1 to 1 set enable2 0, // set input enable2 to 0 -// The clock is also controlled in the test file using tick and tock. Tick is a positive -// pulse and tock takes the clock back to 0. Clock cycles can be run multiple times in -// a row with no other changes to inputs or outputs. +// The clock is also controlled in the test file using tick and tock. Tick is a +// positive pulse and tock takes the clock back to 0. Clock cycles can be run +// multiple times in a row with no other changes to inputs or outputs. tick, tock, -// Finally we output the first expected value (from the test file) which is then compared -// with the first line of real output from our HDL circuit. This output +// Finally we output the first expected value (from the test file) which is then +// compared with the first line of real output from our HDL circuit. This output // can be viewed in the .out file. output; -// An example of , a chip that takes in a 4 bit value as input and adds 1 to -// that value could have the following as test code: +// An example of , a chip that takes in a 4 bit value as input and +// adds 1 to that value could have the following as test code: // Set the input value to 0000, clock pulse, compare output from cmp file to actual out. set in %B0000, @@ -183,17 +184,17 @@ tick, tock, output; -// The expected output for case 1 should be 0001 and case 2 expects 0111, lets learn -// a little more about comparison files before finalizing our lesson. +// The expected output for case 1 should be 0001 and case 2 expects 0111, lets +// learn a little more about comparison files before finalizing our lesson. ``` ## Comparison Files -Now lets take a look at comparison files, the files that hold what the test file compares -with the actual output of an HDL chip in the hardware simulator! +Now lets take a look at comparison files, the files that hold what the test file +compares with the actual output of an HDL chip in the hardware simulator! ```verilog -// Like the example above, the structure of the comparison file would look -// something like this +// Like the example above, the structure of the comparison file +// would look something like this | in | out | | 0000 | 0001 | | 0110 | 0111 | -- cgit v1.2.3 From 05018243abce940afe4e221054759d588e812342 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20de=20Santa?= Date: Thu, 24 Oct 2019 12:20:33 -0300 Subject: Fix language typos in clojure-macros-pt.html.markdown --- pt-br/clojure-macros-pt.html.markdown | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/pt-br/clojure-macros-pt.html.markdown b/pt-br/clojure-macros-pt.html.markdown index d56840e0..c686bb80 100644 --- a/pt-br/clojure-macros-pt.html.markdown +++ b/pt-br/clojure-macros-pt.html.markdown @@ -13,15 +13,15 @@ do Clojure lhe dá acesso a toda a extensão da linguagem para escrever rotinas de geração de código chamados "macros". Macros fornecem uma poderosa forma de adequar a linguagem às suas necessidades. -Pórem Tenha cuidado. É considerado má pratica escrever uma macro quando uma função vai fazer. Use uma macro apenas -quando você precisar do controle sobre quando ou se os argumentos para um formulário será avaliado. +Pórem, tenha cuidado. É considerado má pratica escrever uma macro quando uma função vai fazer. Use uma macro apenas +quando você precisar de controle sobre quando ou se os argumentos de um formulário serão avaliados. Você vai querer estar familiarizado com Clojure. Certifique-se de entender tudo em -[Clojure em Y Minutos](/docs/clojure/). +[Aprenda Clojure em Y Minutos](/docs/clojure/). ```clojure -;; Defina uma macro utilizando defmacro. Sua macro deve ter como saida uma lista que possa -;; ser avaliada como codigo Clojure. +;; Defina uma macro utilizando defmacro. Sua macro deve ter como saída uma lista que possa +;; ser avaliada como código Clojure. ;; ;; Essa macro é a mesma coisa que se você escrever (reverse "Hello World") (defmacro my-first-macro [] @@ -33,14 +33,14 @@ Você vai querer estar familiarizado com Clojure. Certifique-se de entender tudo (macroexpand '(my-first-macro)) ;; -> (# "Hello World") -;; Você pode avaliar o resultad de macroexpand diretamente: +;; Você pode avaliar o resultado de macroexpand diretamente: (eval (macroexpand '(my-first-macro))) ; -> (\d \l \o \r \W \space \o \l \l \e \H) -;; mas você deve usar esse mais suscinto, sintax como de função: +;; mas você deve usar essa sintaxe mais sucinta e familiar a funções: (my-first-macro) ; -> (\d \l \o \r \W \space \o \l \l \e \H) -;; Você pode tornar as coisas mais faceis pra você, utilizando a sintaxe de citação mais suscinta +;; Você pode tornar as coisas mais fáceis pra você, utilizando a sintaxe de citação mais suscinta ;; para criar listas nas suas macros: (defmacro my-first-quoted-macro [] '(reverse "Hello World")) -- cgit v1.2.3 From 0af4996d08c550144cf368f0fd6e0693294896a0 Mon Sep 17 00:00:00 2001 From: Philippe Coval Date: Fri, 25 Oct 2019 11:35:24 +0200 Subject: [ansible/en]: Fix quotes in command line example Change-Id: I46fe48764029d243b211cef04f06fdf62ea39219 Forwarded: https://github.com/adambard/learnxinyminutes-docs/pull/3729 Signed-off-by: Philippe Coval --- ansible.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ansible.html.markdown b/ansible.html.markdown index 41a8c9b5..bfb1406b 100644 --- a/ansible.html.markdown +++ b/ansible.html.markdown @@ -513,7 +513,7 @@ $ # Now we would run the above playbook with roles You can use the jinja in the CLI too ```bash -ansible -m shell -a 'echo {{ my_variable }}` -e 'my_variable=something, playbook_parameter=twentytwo" localhost +ansible -m shell -a 'echo {{ my_variable }}' -e 'my_variable=something, playbook_parameter=twentytwo' localhost ``` In fact - jinja is used to template parts of the playbooks too -- cgit v1.2.3 From 7e27297ea555764a5e690f251205d9323b349bb2 Mon Sep 17 00:00:00 2001 From: Kyle Mendes Date: Sun, 27 Oct 2019 12:41:50 -0500 Subject: Formatting the dart example --- dart.html.markdown | 78 +++++++++++++++++++++++++++++++++++++++--------------- 1 file changed, 57 insertions(+), 21 deletions(-) diff --git a/dart.html.markdown b/dart.html.markdown index 07f755f7..dec2c904 100644 --- a/dart.html.markdown +++ b/dart.html.markdown @@ -29,6 +29,7 @@ example1() { nested2() => print("Example1 nested 1 nested 2"); nested2(); } + nested1(); } @@ -37,6 +38,7 @@ example2() { nested1(fn) { fn(); } + nested1(() => print("Example2 nested 1")); } @@ -47,9 +49,12 @@ example3() { planA(fn(informSomething)) { fn("Example3 plan A"); } - planB(fn) { // Or don't declare number of parameters. + + planB(fn) { + // Or don't declare number of parameters. fn("Example3 plan B"); } + planA((s) => print(s)); planB((s) => print(s)); } @@ -60,17 +65,20 @@ example4() { nested1(fn(informSomething)) { fn(example4Something); } + nested1((s) => print(s)); } // Class declaration with a sayIt method, which also has closure access // to the outer variable as though it were a function as seen before. var example5method = "Example5 sayIt"; + class Example5Class { sayIt() { print(example5method); } } + example5() { // Create an anonymous instance of the Example5Class and call the sayIt // method on it. @@ -86,6 +94,7 @@ class Example6Class { print(instanceVariable); } } + example6() { new Example6Class().sayIt(); } @@ -96,10 +105,12 @@ class Example7Class { static sayItFromClass() { print(classVariable); } + sayItFromInstance() { print(classVariable); } } + example7() { Example7Class.sayItFromClass(); new Example7Class().sayItFromInstance(); @@ -111,7 +122,7 @@ example7() { // by default. But arrays and maps are not. They can be made constant by // declaring them "const". var example8Array = const ["Example8 const array"], - example8Map = const {"someKey": "Example8 const map"}; + example8Map = const {"someKey": "Example8 const map"}; example8() { print(example8Array[0]); print(example8Map["someKey"]); @@ -172,6 +183,7 @@ example13() { print("Example13 regexp doesn't match '${s}'"); } } + match(s1); match(s2); } @@ -190,7 +202,7 @@ example14() { } // dynamic typed null can be convert to bool - var b;// b is dynamic type + var b; // b is dynamic type b = "abc"; try { if (b) { @@ -240,9 +252,11 @@ example15() { // StringBuffer. Or you could join a string array. example16() { var sb = new StringBuffer(), a = ["a", "b", "c", "d"], e; - for (e in a) { sb.write(e); } + for (e in a) { + sb.write(e); + } print("Example16 dynamic string created with " - "StringBuffer '${sb.toString()}'"); + "StringBuffer '${sb.toString()}'"); print("Example16 join string array '${a.join()}'"); } @@ -302,11 +316,13 @@ class Example21 { set names(List list) { _names = list; } + int get length => _names.length; void add(String name) { _names.add(name); } } + void example21() { Example21 o = new Example21(); o.add("c"); @@ -320,7 +336,9 @@ class Example22A { var _name = "Some Name!"; get name => _name; } + class Example22B extends Example22A {} + example22() { var o = new Example22B(); print("Example22 class inheritance '${o.name}'"); @@ -334,19 +352,21 @@ example22() { // single inheritance doesn't get in the way of reusable code. // Mixins follow the "with" statement during the class declaration. class Example23A {} + class Example23Utils { addTwo(n1, n2) { return n1 + n2; } } + class Example23B extends Example23A with Example23Utils { addThree(n1, n2, n3) { return addTwo(n1, n2) + n3; } } + example23() { - var o = new Example23B(), r1 = o.addThree(1, 2, 3), - r2 = o.addTwo(1, 2); + var o = new Example23B(), r1 = o.addThree(1, 2, 3), r2 = o.addTwo(1, 2); print("Example23 addThree(1, 2, 3) results in '${r1}'"); print("Example23 addTwo(1, 2) results in '${r2}'"); } @@ -362,12 +382,13 @@ class Example24A { } get value => _value; } + class Example24B extends Example24A { Example24B({value: "someOtherValue"}) : super(value: value); } + example24() { - var o1 = new Example24B(), - o2 = new Example24B(value: "evenMore"); + var o1 = new Example24B(), o2 = new Example24B(value: "evenMore"); print("Example24 calling super during constructor '${o1.value}'"); print("Example24 calling super during constructor '${o2.value}'"); } @@ -379,10 +400,11 @@ class Example25 { var value, anotherValue; Example25({this.value, this.anotherValue}); } + example25() { var o = new Example25(value: "a", anotherValue: "b"); print("Example25 shortcut for constructor '${o.value}' and " - "'${o.anotherValue}'"); + "'${o.anotherValue}'"); } // Named parameters are available when declared between {}. @@ -394,17 +416,19 @@ example26() { _name = name; _surname = surname; } + setConfig2(name, [surname, email]) { _name = name; _surname = surname; _email = email; } + setConfig1(surname: "Doe", name: "John"); print("Example26 name '${_name}', surname '${_surname}', " - "email '${_email}'"); + "email '${_email}'"); setConfig2("Mary", "Jane"); print("Example26 name '${_name}', surname '${_surname}', " - "email '${_email}'"); + "email '${_email}'"); } // Variables declared with final can only be set once. @@ -416,6 +440,7 @@ class Example27 { // that follows the : Example27({this.color1, color2}) : color2 = color2; } + example27() { final color = "orange", o = new Example27(color1: "lilac", color2: "white"); print("Example27 color is '${color}'"); @@ -434,6 +459,7 @@ class Example28 extends IterableBase { } get iterator => names.iterator; } + example28() { var o = new Example28(); o.forEach((name) => print("Example28 '${name}'")); @@ -459,10 +485,12 @@ example29() { callItForMe(fn()) { return fn(); } + rand() { v = new DM.Random().nextInt(50); return v; } + while (true) { print("Example29 callItForMe(rand) '${callItForMe(rand)}'"); if (v != 30) { @@ -477,8 +505,12 @@ example29() { // Parse int, convert double to int, or just keep int when dividing numbers // by using the ~/ operation. Let's play a guess game too. example30() { - var gn, tooHigh = false, - n, n2 = (2.0).toInt(), top = int.parse("123") ~/ n2, bottom = 0; + var gn, + tooHigh = false, + n, + n2 = (2.0).toInt(), + top = int.parse("123") ~/ n2, + bottom = 0; top = top ~/ 6; gn = new DM.Random().nextInt(top + 1); // +1 because nextInt top is exclusive print("Example30 Guess a number between 0 and ${top}"); @@ -488,10 +520,11 @@ example30() { } else { tooHigh = n > gn; print("Example30 Number ${n} is too " - "${tooHigh ? 'high' : 'low'}. Try again"); + "${tooHigh ? 'high' : 'low'}. Try again"); } return n == gn; } + n = (top - bottom) ~/ 2; while (!guessNumber(n)) { if (tooHigh) { @@ -510,12 +543,15 @@ example30() { // the program needs to startup with. main() { print("Learn Dart in 15 minutes!"); - [example1, example2, example3, example4, example5, example6, example7, - example8, example9, example10, example11, example12, example13, example14, - example15, example16, example17, example18, example19, example20, - example21, example22, example23, example24, example25, example26, - example27, example28, example29, example30 - ].forEach((ef) => ef()); + [ + example1, example2, example3, example4, example5, + example6, example7, example8, example9, example10, + example11, example12, example13, example14, example15, + example16, example17, example18, example19, example20, + example21, example22, example23, example24, example25, + example26, example27, example28, example29, + example30 // Adding this comment stops the dart formatter from putting all items on a new line + ].forEach((ef) => ef()); } ``` -- cgit v1.2.3 From daa3502767283a3fd0922d2e5cde2bdb779328b0 Mon Sep 17 00:00:00 2001 From: Raul Almeida <36135994+almeidaraul@users.noreply.github.com> Date: Tue, 29 Oct 2019 15:26:15 -0300 Subject: Add command tips and examples, fix wild text Added information under "Alguns atalhos e dicas" and "Macros"; removed some wild text in the header (essentially, one of the contributors was one of vim's modes) --- pt-br/vim-pt.html.markdown | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/pt-br/vim-pt.html.markdown b/pt-br/vim-pt.html.markdown index d7617bbe..cc304381 100644 --- a/pt-br/vim-pt.html.markdown +++ b/pt-br/vim-pt.html.markdown @@ -5,6 +5,7 @@ contributors: - ["RadhikaG", "https://github.com/RadhikaG"] translators: - ["David Lima", "https://github.com/davelima"] + - ["Raul Almeida", "https://github.com/almeidaraul"] lang: pt-br filename: LearnVim-pt.txt --- @@ -24,6 +25,7 @@ para agilizar a navegação para pontos específicos no arquivo, além de ediç :w # Salva o arquivo atual :wq # Salva o arquivo e fecha o vim :q! # Fecha o vim e descarta as alterações no arquivo + # ! depois de qualquer comando força a sua execução # ! *força* :q a executar, fechando o vim sem salvar antes :x # Salva o arquivo e fecha o vim (atalho para :wq) @@ -158,7 +160,15 @@ Alguns exemplos importantes de 'Verbos', 'Modificadores' e 'Nomes': :earlier 15m # Reverte o documento para como ele estava há 15 minutos atrás :later 15m # Reverte o comando acima ddp # Troca linhas consecutivas de posição, dd e depois p + xp # Permuta caractere atual e o seguinte + Xp # Permuta caractere atual e o anterior . # Repete a última ação + + # Em geral, o usuário pode associar um comando em maísculas (exemplo: D) com + # "executar este comando até o final da linha" + + # Usar a tecla de um comando duas vezes geralmente significa executar este + # comando sobre toda a linha (exemplo: dd apaga a linha inteira) ``` ## Macros @@ -172,6 +182,7 @@ exatamente a mesma sequencia de ações e comandos na seleção atual. qa # Inicia a gravação de uma macro chamado 'a' q # Para a gravação @a # Executa a macro + @@ # Executa a última macro executada ``` ### Configurando o ~/.vimrc -- cgit v1.2.3 From 87b2be61024a7ccc1e8cb66a3b8e1cccffb8deee Mon Sep 17 00:00:00 2001 From: Raul Almeida <36135994+almeidaraul@users.noreply.github.com> Date: Tue, 29 Oct 2019 19:53:29 -0300 Subject: Update contributors in pascal-pt I translated this a while back and decided to add myself as a contributor besides a translator because I changed much of the original text to what I feel is a more legible, better explanation of the Pascal language. --- pt-br/pascal-pt.html.markdown | 1 + 1 file changed, 1 insertion(+) diff --git a/pt-br/pascal-pt.html.markdown b/pt-br/pascal-pt.html.markdown index 3a37271a..749b2d0d 100644 --- a/pt-br/pascal-pt.html.markdown +++ b/pt-br/pascal-pt.html.markdown @@ -4,6 +4,7 @@ filename: learnpascal-pt.pas contributors: - ["Ganesha Danu", "https://github.com/blinfoldking"] - ["Keith Miyake", "https//github.com/kaymmm"] + - ["Raul Almeida", "https://github.com/almeidaraul"] translators: - ["Raul Almeida", "https://github.com/almeidaraul"] lang: pt-br -- cgit v1.2.3 From 6e1f2df651ca7f3349705c7b545600e0b54fc30a Mon Sep 17 00:00:00 2001 From: retoc Date: Thu, 31 Oct 2019 20:46:49 +0100 Subject: updated link to java coding guidelines, the old one is broken --- de-de/java-de.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/de-de/java-de.html.markdown b/de-de/java-de.html.markdown index e8ac5bda..e52087ec 100644 --- a/de-de/java-de.html.markdown +++ b/de-de/java-de.html.markdown @@ -477,7 +477,7 @@ Für tiefergreifende Fragen ist Google der beste Startpunkt. * [Generics](http://docs.oracle.com/javase/tutorial/java/generics/index.html) -* [Java Code Conventions](http://www.oracle.com/technetwork/java/codeconv-138413.html) +* [Java Code Conventions](https://www.oracle.com/technetwork/java/codeconventions-150003.pdf) **Online Tutorials** -- cgit v1.2.3 From dfc80dc81355725c3461826a30c50d9eebfc04b6 Mon Sep 17 00:00:00 2001 From: Kyle Mendes Date: Thu, 31 Oct 2019 18:37:56 -0500 Subject: Update Sass Example to use proper syntax highlighting --- sass.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sass.html.markdown b/sass.html.markdown index 224db80e..860e550a 100644 --- a/sass.html.markdown +++ b/sass.html.markdown @@ -16,7 +16,7 @@ This tutorial is written using SCSS. If you're already familiar with CSS3, you'll be able to pick up Sass relatively quickly. It does not provide any new styling properties but rather the tools to write your CSS more efficiently and make maintenance much easier. -```sass +```scss //Single line comments are removed when Sass is compiled to CSS. -- cgit v1.2.3 From 9c18774c349cbb0821f59f77c6fff3908139bff7 Mon Sep 17 00:00:00 2001 From: hamidra Date: Fri, 1 Nov 2019 20:49:53 -0700 Subject: add downcast to the tutorial --- swift.html.markdown | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/swift.html.markdown b/swift.html.markdown index 1f9fe897..8582131a 100644 --- a/swift.html.markdown +++ b/swift.html.markdown @@ -692,6 +692,11 @@ print(mySquare.sideLength) // 4 // cast instance let aShape = mySquare as Shape +// downcast instance: +// Because downcasting can fail, the result can be an optional (as?) or an implicitly unwrpped optional (as!). +let anOptionalSquare = aShape as? Square // This will return nil if aShape is not a Square +let aSquare = aShape as! Square // This will throw a runtime error if aShape is not a Square + // compare instances, not the same as == which compares objects (equal to) if mySquare === mySquare { print("Yep, it's mySquare") -- cgit v1.2.3 From f27686677752dca4d715f796aa0cc759bc05f998 Mon Sep 17 00:00:00 2001 From: David Sampson Date: Mon, 4 Nov 2019 10:51:48 -0600 Subject: Info on typeclasses and types --- haskell.html.markdown | 149 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 145 insertions(+), 4 deletions(-) diff --git a/haskell.html.markdown b/haskell.html.markdown index 90d47c27..f3b84bdd 100644 --- a/haskell.html.markdown +++ b/haskell.html.markdown @@ -293,7 +293,13 @@ foldr (\x y -> 2*x + y) 4 [1,2,3] -- 16 -- 7. Data Types ---------------------------------------------------- --- Here's how you make your own data type in Haskell +-- A data type is declared with a 'type constructor' on the left +-- and one or more 'data constructors' on the right, separated by +-- the pipe | symbol. This is a sum/union type. Each data constructor +-- is a (possibly nullary) function that creates an object of the type +-- named by the type constructor. + +-- This is essentially an enum data Color = Red | Blue | Green @@ -304,7 +310,57 @@ say Red = "You are Red!" say Blue = "You are Blue!" say Green = "You are Green!" --- Your data types can have parameters too: +-- Note that the type constructor is used in the type signature +-- and the data constructors are used in the body of the function +-- Data constructors are primarily pattern-matched against + +-- This next one is a traditional container type holding two fields +-- In a type declaration, data constructors take types as parameters +-- Data constructors can have the same name as type constructors +-- This is common where the type only has a single data constructor + +data Point = Point Float Float + +-- This can be used in a function like: + +distance :: Point -> Point -> Float +distance (Point x y) (Point x' y') = sqrt $ dx + dy + where dx = (x - x') ** 2 + dy = (y - y') ** 2 + +-- Types can have multiple data constructors with arguments, too + +data Name = Mononym String | FirstLastName String String | FullName String String String + +-- To make things clearer we can use record syntax + +data Point2D = CartesianPoint2D { x :: Float, y :: Float } | PolarPoint2D { r :: Float, theta :: Float } + +myPoint = CartesianPoint2D { x = 7.0, y = 10.0 } + +-- Using record syntax automatically creates accessor functions (the name of the field) + +xOfMyPoint = x myPoint + +-- xOfMyPoint is equal to 7.0 + +-- Record syntax also allows a simple form of update + +myPoint' = myPoint { x = 9.0 } + +-- myPoint' is CartesianPoint2D { x = 9.0, y = 10.0 } + +-- Even if a type is defined with record syntax, it can be declared like +-- a simple data constructor. This is fine: + +myPoint'2 = CartesianPoint2D 3.3 4.0 + +-- It's also useful to pattern match data constructors in `case` expressions + +distanceFromOrigin x = case x of (CartesianPoint2D x y) -> sqrt $ x ** 2 + y ** 2 + (PolarPoint2D r _) -> r + +-- Your data types can have type parameters too: data Maybe a = Nothing | Just a @@ -313,8 +369,93 @@ Just "hello" -- of type `Maybe String` Just 1 -- of type `Maybe Int` Nothing -- of type `Maybe a` for any `a` +-- For convenience we can also create type synonyms with the 'type' keyword + +type String = [Char] + +-- Unlike `data` types, type synonyms need no constructor, and can be used +-- anywhere a synonymous data type could be used. Say we have the +-- following type synonyms and items with the following type signatures + +type Weight = Float +type Height = Float +type Point = (Float, Float) +getMyHeightAndWeight :: Person -> (Height, Weight) +findCenter :: Circle -> Point +somePerson :: Person +someCircle :: Circle +distance :: Point -> Point -> Float + +-- The following would compile and run without issue, even though it does not make +-- sense semantically, because the type synonyms reduce to the same base types + +distance (getMyHeightAndWeight somePerson) (findCenter someCircle) + +---------------------------------------------------- +-- 8. Typeclasses +---------------------------------------------------- + +-- Typeclasses are one way Haskell does polymorphism +-- They are similar to interfaces in other languages +-- A typeclass defines a set of functions that must work on any type that is in +-- that typeclass. + +-- The Eq typeclass is for types whose instances can be tested for equality with one another + +class Eq a where + (==) :: a -> a -> Bool + (/=) :: a -> a -> Bool + x == y = not (x /= y) + x /= y = not (x == y) + +-- This defines a typeclass that requires two functions, (==) and (/=) +-- It also declares that one function can be declared in terms of another +-- So it is enough that *either* the (==) function or the (/=) is defined +-- And the other will be 'filled in' based on the typeclass definition + +-- To make a type a member of a type class, the instance keyword is used + +instance Eq TrafficLight where + Red == Red = True + Green == Green = True + Yellow == Yellow = True + _ == _ = False + +-- Now we can use (==) and (/=) with TrafficLight objects + +canProceedThrough :: TrafficLight -> Bool +canProceedThrough t = t /= Red + +-- You can NOT create an instance definition for a type synonym + +-- Functions can be written to take typeclasses with type parameters, rather than types, +-- assuming that the function only relies on features of the typeclass + +isEqual (Eq a) => a -> a -> Bool +isEqual x y = x == y + +-- Note that x and y MUST be the same type, as they are both defined as being of type parameter 'a' +-- A typeclass does state that different types in the typeclass can be mixed together +-- So `isEqual Red 2` is invalid, even though 2 is an Int which is an instance of Eq, and Red is +-- a TrafficLight which is also an instance of Eq + +-- Other common typeclasses are: +-- Ord for types that can be ordered, allowing you to use >, <=, etc. +-- Read for types that can be created from a string representation +-- Show for types that can be converted to a string for display +-- Num, Real, Integral, Fractional for types that can do mathematical calculation +-- Enum for types that can be stepped through +-- Bounded for types with a maximum and minimum + +-- Haskell can automatically make types part of Eq, Ord, Read, Show, Enum, and Bounded +-- with the `deriving` keyword at the end of the type declaration + +data Point = Point Float Float deriving (Eq, Read, Show) + +-- In this case it is NOT necessary to create an 'instance' definition + ---------------------------------------------------- --- 8. Haskell IO +-- 9. Haskell IO ---------------------------------------------------- -- While IO can't be explained fully without explaining monads, @@ -395,7 +536,7 @@ main'' = do ---------------------------------------------------- --- 9. The Haskell REPL +-- 10. The Haskell REPL ---------------------------------------------------- -- Start the repl by typing `ghci`. -- cgit v1.2.3 From 35fc26b754a8696e505024c5b364d54e7adcde60 Mon Sep 17 00:00:00 2001 From: David Sampson Date: Mon, 4 Nov 2019 11:05:21 -0600 Subject: fixed line lengths --- haskell.html.markdown | 48 +++++++++++++++++++++++++++++------------------- 1 file changed, 29 insertions(+), 19 deletions(-) diff --git a/haskell.html.markdown b/haskell.html.markdown index f3b84bdd..1cc79ec9 100644 --- a/haskell.html.markdown +++ b/haskell.html.markdown @@ -330,15 +330,19 @@ distance (Point x y) (Point x' y') = sqrt $ dx + dy -- Types can have multiple data constructors with arguments, too -data Name = Mononym String | FirstLastName String String | FullName String String String +data Name = Mononym String + | FirstLastName String String + | FullName String String String -- To make things clearer we can use record syntax -data Point2D = CartesianPoint2D { x :: Float, y :: Float } | PolarPoint2D { r :: Float, theta :: Float } +data Point2D = CartesianPoint2D { x :: Float, y :: Float } + | PolarPoint2D { r :: Float, theta :: Float } myPoint = CartesianPoint2D { x = 7.0, y = 10.0 } --- Using record syntax automatically creates accessor functions (the name of the field) +-- Using record syntax automatically creates accessor functions +-- (the name of the field) xOfMyPoint = x myPoint @@ -357,8 +361,9 @@ myPoint'2 = CartesianPoint2D 3.3 4.0 -- It's also useful to pattern match data constructors in `case` expressions -distanceFromOrigin x = case x of (CartesianPoint2D x y) -> sqrt $ x ** 2 + y ** 2 - (PolarPoint2D r _) -> r +distanceFromOrigin x = + case x of (CartesianPoint2D x y) -> sqrt $ x ** 2 + y ** 2 + (PolarPoint2D r _) -> r -- Your data types can have type parameters too: @@ -386,8 +391,9 @@ somePerson :: Person someCircle :: Circle distance :: Point -> Point -> Float --- The following would compile and run without issue, even though it does not make --- sense semantically, because the type synonyms reduce to the same base types +-- The following would compile and run without issue, +-- even though it does not make sense semantically, +-- because the type synonyms reduce to the same base types distance (getMyHeightAndWeight somePerson) (findCenter someCircle) @@ -397,10 +403,11 @@ distance (getMyHeightAndWeight somePerson) (findCenter someCircle) -- Typeclasses are one way Haskell does polymorphism -- They are similar to interfaces in other languages --- A typeclass defines a set of functions that must work on any type that is in --- that typeclass. +-- A typeclass defines a set of functions that must +-- work on any type that is in that typeclass. --- The Eq typeclass is for types whose instances can be tested for equality with one another +-- The Eq typeclass is for types whose instances can +-- be tested for equality with one another. class Eq a where (==) :: a -> a -> Bool @@ -428,27 +435,30 @@ canProceedThrough t = t /= Red -- You can NOT create an instance definition for a type synonym --- Functions can be written to take typeclasses with type parameters, rather than types, --- assuming that the function only relies on features of the typeclass +-- Functions can be written to take typeclasses with type parameters, +-- rather than types, assuming that the function only relies on +-- features of the typeclass isEqual (Eq a) => a -> a -> Bool isEqual x y = x == y --- Note that x and y MUST be the same type, as they are both defined as being of type parameter 'a' --- A typeclass does state that different types in the typeclass can be mixed together --- So `isEqual Red 2` is invalid, even though 2 is an Int which is an instance of Eq, and Red is --- a TrafficLight which is also an instance of Eq +-- Note that x and y MUST be the same type, as they are both defined +-- as being of type parameter 'a'. +-- A typeclass does not state that different types in the typeclass can +-- be mixed together. +-- So `isEqual Red 2` is invalid, even though 2 is an Int which is an +-- instance of Eq, and Red is a TrafficLight which is also an instance of Eq -- Other common typeclasses are: -- Ord for types that can be ordered, allowing you to use >, <=, etc. -- Read for types that can be created from a string representation -- Show for types that can be converted to a string for display --- Num, Real, Integral, Fractional for types that can do mathematical calculation +-- Num, Real, Integral, Fractional for types that can do math -- Enum for types that can be stepped through -- Bounded for types with a maximum and minimum --- Haskell can automatically make types part of Eq, Ord, Read, Show, Enum, and Bounded --- with the `deriving` keyword at the end of the type declaration +-- Haskell can automatically make types part of Eq, Ord, Read, Show, Enum, +-- and Bounded with the `deriving` keyword at the end of the type declaration data Point = Point Float Float deriving (Eq, Read, Show) -- cgit v1.2.3 From b27d3a088db2fac2324df2a05330801afee2e92b Mon Sep 17 00:00:00 2001 From: Rett Berg Date: Sat, 16 Nov 2019 12:38:14 -0700 Subject: add example of how stack might be managed --- wasm.html.markdown | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+) diff --git a/wasm.html.markdown b/wasm.html.markdown index 98bfc000..92831e69 100644 --- a/wasm.html.markdown +++ b/wasm.html.markdown @@ -222,6 +222,92 @@ contributors: ) ) (export "apply_cos64" (func $apply_cos64)) + + ;; Demonstration of how this C code might be written by hand + ;; + ;; typedef struct { + ;; int a; + ;; int b; + ;; } sum_struct_t; + ;; + ;; sum_struct_t sum_struct_create(int a, int b) { + ;; return (sum_struct_t){a, b}; + ;; } + ;; + ;; int sum_local() { + ;; sum_struct_t s = sum_struct_create(40, 2); + ;; return s.a + s.b; + ;; } + ;; + ;; Wasm is a stack-based language, but for returning values more complicated + ;; than an int/float, a memory stack has to be manually managed. One ;; + ;; approach is to use a mutable global to store the stack_ptr. We give + ;; ourselves 1MiB of mem-stack and grow it downwards. + ;; + ;; Note: we are differentiating from the memstack (stack stored in memory) + ;; and the "stack", which wasm implicitly uses to to pass and return values. + (global $memstack_ptr (mut i32) (i32.const 65536)) + + ;; structs can only be returned by reference + (func $sum_struct_create + (param $sum_struct_ptr i32) + (param $var$a i32) + (param $var$b i32) + ;; c// sum_struct_ptr->a = a; + (i32.store + (get_local $sum_struct_ptr) + (get_local $var$a) + ) + + ;; c// sum_struct_ptr->b = b; + (i32.store offset=4 + (get_local $sum_struct_ptr) + (get_local $var$b) + ) + ) + + (func $sum_local (result i32) + (local $var$sum_struct$a i32) + (local $var$sum_struct$b i32) + (local $local_memstack_ptr i32) + + ;; reserve stack space + (i32.sub + (get_global $memstack_ptr) + (i32.const 8) + ) + tee_local $local_memstack_ptr ;; tee both stores and returns given value + set_global $memstack_ptr + + ;; call the function, storing the result in the stack + (call $sum_struct_create + ((;$sum_struct_ptr=;) get_local $local_memstack_ptr) + ((;$var$a=;) i32.const 40) + ((;$var$b=;) i32.const 2) + ) + + ;; retrieve values from struct + (set_local $var$sum_struct$a + (i32.load offset=0 (get_local $local_memstack_ptr)) + ) + (set_local $var$sum_struct$b + (i32.load offset=4 (get_local $local_memstack_ptr)) + ) + + ;; unreserve stack space + (set_global $memstack_ptr + (i32.add + (get_local $local_memstack_ptr) + (i32.const 8) + ) + ) + + (i32.add + (get_local $var$sum_struct$a) + (get_local $var$sum_struct$b) + ) + ) + (export "sum_local" (func $sum_local)) ) ``` -- cgit v1.2.3 From 4727925b1aef7f030adb8ae76bf7562a6280b54e Mon Sep 17 00:00:00 2001 From: Rett Berg Date: Sat, 16 Nov 2019 12:44:47 -0700 Subject: update comments a bit --- wasm.html.markdown | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/wasm.html.markdown b/wasm.html.markdown index 92831e69..d62539b8 100644 --- a/wasm.html.markdown +++ b/wasm.html.markdown @@ -223,7 +223,12 @@ contributors: ) (export "apply_cos64" (func $apply_cos64)) - ;; Demonstration of how this C code might be written by hand + ;; Wasm is a stack-based language, but for returning values more complicated + ;; than an int/float, a memory stack has to be manually managed. One + ;; approach is to use a mutable global to store the stack_ptr. We give + ;; ourselves 1MiB of mem-stack and grow it downwards. + ;; + ;; Below is a demonstration of how this C code **might** be written by hand ;; ;; typedef struct { ;; int a; @@ -238,17 +243,11 @@ contributors: ;; sum_struct_t s = sum_struct_create(40, 2); ;; return s.a + s.b; ;; } - ;; - ;; Wasm is a stack-based language, but for returning values more complicated - ;; than an int/float, a memory stack has to be manually managed. One ;; - ;; approach is to use a mutable global to store the stack_ptr. We give - ;; ourselves 1MiB of mem-stack and grow it downwards. - ;; - ;; Note: we are differentiating from the memstack (stack stored in memory) - ;; and the "stack", which wasm implicitly uses to to pass and return values. + + ;; Unlike C, we must manage our own memory stack (global $memstack_ptr (mut i32) (i32.const 65536)) - ;; structs can only be returned by reference + ;; Structs can only be returned by reference (func $sum_struct_create (param $sum_struct_ptr i32) (param $var$a i32) -- cgit v1.2.3 From 0427cb31681114e3d4c2bf664c37d17aa82a7f59 Mon Sep 17 00:00:00 2001 From: Rett Berg Date: Sat, 16 Nov 2019 12:47:32 -0700 Subject: more comment updates --- wasm.html.markdown | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/wasm.html.markdown b/wasm.html.markdown index d62539b8..aba2084f 100644 --- a/wasm.html.markdown +++ b/wasm.html.markdown @@ -224,9 +224,9 @@ contributors: (export "apply_cos64" (func $apply_cos64)) ;; Wasm is a stack-based language, but for returning values more complicated - ;; than an int/float, a memory stack has to be manually managed. One + ;; than an int/float, a separate memory stack has to be manually managed. One ;; approach is to use a mutable global to store the stack_ptr. We give - ;; ourselves 1MiB of mem-stack and grow it downwards. + ;; ourselves 1MiB of memstack and grow it downwards. ;; ;; Below is a demonstration of how this C code **might** be written by hand ;; @@ -244,7 +244,7 @@ contributors: ;; return s.a + s.b; ;; } - ;; Unlike C, we must manage our own memory stack + ;; Unlike C, we must manage our own memory stack. We reserve 1MiB (global $memstack_ptr (mut i32) (i32.const 65536)) ;; Structs can only be returned by reference @@ -270,7 +270,7 @@ contributors: (local $var$sum_struct$b i32) (local $local_memstack_ptr i32) - ;; reserve stack space + ;; reserve memstack space (i32.sub (get_global $memstack_ptr) (i32.const 8) @@ -278,7 +278,7 @@ contributors: tee_local $local_memstack_ptr ;; tee both stores and returns given value set_global $memstack_ptr - ;; call the function, storing the result in the stack + ;; call the function, storing the result in the memstack (call $sum_struct_create ((;$sum_struct_ptr=;) get_local $local_memstack_ptr) ((;$var$a=;) i32.const 40) @@ -293,7 +293,7 @@ contributors: (i32.load offset=4 (get_local $local_memstack_ptr)) ) - ;; unreserve stack space + ;; unreserve memstack space (set_global $memstack_ptr (i32.add (get_local $local_memstack_ptr) -- cgit v1.2.3 From 1aec529fa9c0cfc54eaa412a7fb959fe03cbc1ee Mon Sep 17 00:00:00 2001 From: Krain Arnold Date: Wed, 20 Nov 2019 15:31:29 +0100 Subject: fix minor typos and spelling errors --- ansible.html.markdown | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/ansible.html.markdown b/ansible.html.markdown index 41a8c9b5..fc656e30 100644 --- a/ansible.html.markdown +++ b/ansible.html.markdown @@ -30,9 +30,9 @@ But ansible is way more! It provides execution plans, an API, library, and callb #### Pros -* It is an agent-less tools In most scenarios, it use ssh as a transport layer. +* It is an agent-less tool. In most scenarios, it uses ssh as a transport layer. In some way you can use it as 'bash on steroids'. -* It is very easy to start. If you are familiar with ssh concept - you already +* It is very easy to start. If you are familiar with the concept of ssh - you already know Ansible (ALMOST). * It executes 'as is' - other tools (salt, puppet, chef - might execute in different scenario than you would expect) @@ -176,7 +176,7 @@ instances in the cloud, execute shell command). The simplest module is called Example of modules: * Module: `ping` - the simplest module that is useful to verify host connectivity -* Module: `shell` - a module that executes shell command on a specified host(s). +* Module: `shell` - a module that executes a shell command on a specified host(s). ```bash @@ -204,13 +204,13 @@ the module subsystem (useful to install python2.7) Execution of a single Ansible **module** is called a **task**. The simplest module is called `ping` as you could see above. -Another example of the module that allow you to execute command remotly on +Another example of the module that allows you to execute a command remotely on multiple resources is called `shell`. See above how you were using them already. ### Playbook **Execution plan** written in a form of script file(s) is called **playbook**. -Playbook consist of multiple elements - +Playbooks consist of multiple elements - * a list (or group) of hosts that 'the play' is executed against * `task(s)` or `role(s)` that are going to be executed * multiple optional settings (like default variables, and way more) @@ -247,7 +247,7 @@ Note: Example playbook is explained in the next chapter: 'Roles' ### Inventory -Inventory is a set of objects or hosts, against which we are executing our +An inventory is a set of objects or hosts, against which we are executing our playbooks or single tasks via shell commands. For these few minutes, let's assume that we are using the default ansible inventory (which in Debian based system is placed in `/etc/ansible/hosts`). @@ -303,8 +303,8 @@ Role can be included in your playbook (executed via your playbook). ``` #### For remaining examples we would use additional repository -This example install ansible in `virtualenv` so it is independend from a system. -You need to initialize it into your shell-context with `source environment.sh` +This example installs ansible in `virtualenv` so it is independent from a system. +You need to initialize it into your shell-context with the `source environment.sh` command. We are going to use this repository with examples: [https://github.com/sirkubax/ansible-for-learnXinYminutes]() @@ -551,7 +551,7 @@ provides a way to encrypt confidential files so you can store them in the repository, yet the files are decrypted on-the-fly during ansible execution. The best way to use it is to store the secret in some secure location, and -configure ansible to use during runtime. +configure ansible to use them during runtime. ```bash # Try (this would fail) @@ -588,7 +588,7 @@ You might like to know, that you can build your inventory dynamically. deliver that to ansible - anything is possible. You do not need to reinvent the wheel - there are plenty of ready to use -inventory scripts for most popular Cloud providers and a lot of in-house +inventory scripts for the most popular Cloud providers and a lot of in-house popular usecases. [AWS example](http://docs.ansible.com/ansible/latest/intro_dynamic_inventory.html#example-aws-ec2-external-inventory-script) @@ -614,7 +614,7 @@ callback_whitelist = profile_tasks ### facts-cache and ansible-cmdb -You can pull some information about your environment from another hosts. +You can pull some information about your environment from another host. If the information does not change - you may consider using a facts_cache to speed things up. -- cgit v1.2.3 From 726d743f2751f2f03d64613321132ca8ec6bdfb4 Mon Sep 17 00:00:00 2001 From: Stanley Lim Date: Thu, 21 Nov 2019 11:33:30 -0500 Subject: [mips/en] Fixed typos --- mips.html.markdown | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/mips.html.markdown b/mips.html.markdown index 4134d3fa..45e16e7b 100644 --- a/mips.html.markdown +++ b/mips.html.markdown @@ -20,12 +20,12 @@ gateways and routers. # Programs typically contain a .data and .text sections .data # Section where data is stored in memory (allocated in RAM), similar to - # variables in higher level languages + # variables in higher-level languages # Declarations follow a ( label: .type value(s) ) form of declaration hello_world: .asciiz "Hello World\n" # Declare a null terminated string num1: .word 42 # Integers are referred to as words - # (32 bit value) + # (32-bit value) arr1: .word 1, 2, 3, 4, 5 # Array of words arr2: .byte 'a', 'b' # Array of chars (1 byte each) @@ -139,7 +139,7 @@ gateways and routers. # The basic format of these branching instructions typically follow # Komm, schaue was das zeigt + Komm, schaue was das zeigt

Das ist ein Absatz.

Das ist ein anderer Absatz.

    @@ -93,12 +93,12 @@ Dieser Artikel ist bedacht darauf, nur HTML Syntax und nützliche Tipps zu geben - - + + - + -- cgit v1.2.3 From d6f4b949d57bfaaaf85e6e8bc93825a575c3ac5b Mon Sep 17 00:00:00 2001 From: caminsha Date: Sat, 18 Jan 2020 00:43:12 +0100 Subject: fixed typos and grammar I have fixed some typos and comama errors in make --- de-de/make-de.html.markdown | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) diff --git a/de-de/make-de.html.markdown b/de-de/make-de.html.markdown index cf90dc29..1bae332c 100644 --- a/de-de/make-de.html.markdown +++ b/de-de/make-de.html.markdown @@ -11,14 +11,14 @@ lang: de-de --- Eine Makefile definiert einen Graphen von Regeln um ein Ziel (oder Ziele) -zu erzeugen. Es dient dazu die geringste Menge an Arbeit zu verrichten um -ein Ziel in einklang mit dem Quellcode zu bringen. Make wurde berühmterweise +zu erzeugen. Es dient dazu, die geringste Menge an Arbeit zu verrichten um +ein Ziel in Einklang mit dem Quellcode zu bringen. Make wurde berühmterweise von Stuart Feldman 1976 übers Wochenende geschrieben. Make ist noch immer -sehr verbreitet (vorallem im Unix umfeld) obwohl es bereits sehr viel +sehr verbreitet (vorallem im Unix Umfeld) obwohl es bereits sehr viel Konkurrenz und Kritik zu Make gibt. -Es gibt eine vielzahl an Varianten von Make, dieser Artikel beschäftig sich -mit der Version GNU Make. Diese Version ist standard auf Linux. +Es gibt eine Vielzahl an Varianten von Make, dieser Artikel beschäftigt sich +mit der Version GNU Make. Diese Version ist Standard auf Linux. ```make @@ -44,14 +44,15 @@ file0.txt: # die erste Regel ist die Standard-Regel. -# Diese Regel wird nur abgearbeitet wenn file0.txt aktueller als file1.txt ist. +# Diese Regel wird nur abgearbeitet, wenn file0.txt aktueller als file1.txt ist. file1.txt: file0.txt cat file0.txt > file1.txt # Verwende die selben Quoting-Regeln wie die Shell @cat file0.txt >> file1.txt # @ unterdrückt die Ausgabe des Befehls an stdout. -@echo 'hello' - # - bedeutet das Make die Abarbeitung fortsetzt auch wenn Fehler passieren. + # - bedeutet, dass Make die Abarbeitung fortsetzt auch wenn Fehler + # passieren. # Versuche `make file1.txt` auf der Kommandozeile. # Eine Regel kann mehrere Ziele und mehrere Voraussetzungen haben. @@ -59,7 +60,7 @@ file2.txt file3.txt: file0.txt file1.txt touch file2.txt touch file3.txt -# Make wird sich beschweren wenn es mehrere Rezepte für die gleiche Regel gibt. +# Make wird sich beschweren, wenn es mehrere Rezepte für die gleiche Regel gibt. # Leere Rezepte zählen nicht und können dazu verwendet werden weitere # Voraussetzungen hinzuzufügen. @@ -67,8 +68,8 @@ file2.txt file3.txt: file0.txt file1.txt # Phony-Ziele #----------------------------------------------------------------------- -# Ein Phony-Ziel ist ein Ziel das keine Datei ist. -# Es wird nie aktuell sein, daher wird Make immer versuchen es abzuarbeiten +# Ein Phony-Ziel ist ein Ziel, das keine Datei ist. +# Es wird nie aktuell sein, daher wird Make immer versuchen, es abzuarbeiten all: maker process # Es ist erlaubt Dinge ausserhalb der Reihenfolge zu deklarieren. @@ -89,14 +90,14 @@ ex0.txt ex1.txt: maker # Automatische Variablen & Wildcards #----------------------------------------------------------------------- -process: file*.txt # Eine Wildcard um Dateinamen zu Vergleichen +process: file*.txt # Eine Wildcard um Dateinamen zu vergleichen @echo $^ # $^ ist eine Variable die eine Liste aller # Voraussetzungen enthält. @echo $@ # Namen des Ziels ausgeben. #(Bei mehreren Ziel-Regeln enthält $@ den Verursacher der Abarbeitung #der Regel.) @echo $< # Die erste Voraussetzung aus der Liste - @echo $? # Nur die Voraussetzungen die nicht aktuell sind. + @echo $? # Nur die Voraussetzungen, die nicht aktuell sind. @echo $+ # Alle Voraussetzungen inklusive Duplikate (nicht wie Üblich) #@echo $| # Alle 'order only' Voraussetzungen @@ -114,20 +115,20 @@ process: ex1.txt file0.txt %.png: %.svg inkscape --export-png $^ -# Muster-Vergleichs-Regeln werden nur abgearbeitet wenn make entscheidet das Ziel zu -# erzeugen +# Muster-Vergleichs-Regeln werden nur abgearbeitet, wenn make entscheidet das +# Ziel zu erzeugen # Verzeichnis-Pfade werden normalerweise bei Muster-Vergleichs-Regeln ignoriert. # Aber make wird versuchen die am besten passende Regel zu verwenden. small/%.png: %.svg inkscape --export-png --export-dpi 30 $^ -# Make wird die letzte Version einer Muster-Vergleichs-Regel verwenden die es +# Make wird die letzte Version einer Muster-Vergleichs-Regel verwenden, die es # findet. %.png: %.svg @echo this rule is chosen -# Allerdings wird make die erste Muster-Vergleicher-Regel verwenden die das +# Allerdings wird make die erste Muster-Vergleicher-Regel verwenden, die das # Ziel erzeugen kann. %.png: %.ps @echo this rule is not chosen if *.svg and *.ps are both present @@ -171,7 +172,7 @@ name4 ?= Jean # nicht gibt. override name5 = David -# Verhindert das Kommando-Zeilen Argumente diese Variable ändern können. +# Verhindert, dass Kommando-Zeilen Argumente diese Variable ändern können. name4 +=grey # Werte an eine Variable anhängen (inkludiert Leerzeichen). @@ -179,9 +180,9 @@ name4 +=grey # Muster-Spezifische Variablen Werte (GNU Erweiterung). echo: name2 = Sara # Wahr innerhalb der passenden Regel und auch innerhalb # rekursiver Voraussetzungen (ausser wenn es den Graphen zerstören - # kann wenn es zu kompilizert wird!) + # kann, wenn es zu kompilizert wird!) -# Ein paar Variablen die von Make automatisch definiert werden. +# Ein paar Variablen, die von Make automatisch definiert werden. echo_inbuilt: echo $(CC) echo ${CXX} @@ -196,7 +197,7 @@ echo_inbuilt: # Variablen 2 #----------------------------------------------------------------------- -# Der erste Typ von Variablen wird bei jeder verwendung ausgewertet. +# Der erste Typ von Variablen wird bei jeder Verwendung ausgewertet. # Das kann aufwendig sein, daher exisitert ein zweiter Typ von Variablen. # Diese werden nur einmal ausgewertet. (Das ist eine GNU make Erweiterung) @@ -215,7 +216,7 @@ var4 ::= good night # Funktionen #----------------------------------------------------------------------- -# Make verfügt über eine vielzahl von Funktionen. +# Make verfügt über eine Vielzahl von Funktionen. sourcefiles = $(wildcard *.c */*.c) objectfiles = $(patsubst %.c,%.o,$(sourcefiles)) -- cgit v1.2.3 From 7d51b05c4108cac0cfb26b87b9d5ce22016df74d Mon Sep 17 00:00:00 2001 From: danielgolf Date: Sun, 19 Jan 2020 23:44:41 +0100 Subject: fixed a typo in bash de-de --- de-de/bash-de.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/de-de/bash-de.html.markdown b/de-de/bash-de.html.markdown index 3fb3e71f..3a76708a 100644 --- a/de-de/bash-de.html.markdown +++ b/de-de/bash-de.html.markdown @@ -157,7 +157,7 @@ echo "#helloworld" | cat > output.out echo "#helloworld" | tee output.out >/dev/null # Löschen der Hilfsdateien von oberhalb, mit Anzeige der Dateinamen -# (mit '-i' für "interactive" erfolgt für jede Date eine Rückfrage) +# (mit '-i' für "interactive" erfolgt für jede Datei eine Rückfrage) rm -v output.out error.err output-and-error.log # Die Ausgabe von Befehlen kann mit Hilfe von $( ) in anderen Befehlen verwendet weden: -- cgit v1.2.3 From dc7996c6e84f38a1cbb7e268c69275c7f19b792a Mon Sep 17 00:00:00 2001 From: Suhayb Alghutaymil Date: Wed, 22 Jan 2020 13:49:33 +0300 Subject: Remove an extra double quote --- php.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/php.html.markdown b/php.html.markdown index 40c9dd01..d4103e97 100644 --- a/php.html.markdown +++ b/php.html.markdown @@ -289,7 +289,7 @@ if (false) { print (false ? 'Does not get printed' : 'Does'); // ternary shortcut operator since PHP 5.3 -// equivalent of "$x ? $x : 'Does'"" +// equivalent of "$x ? $x : 'Does'" $x = false; print($x ?: 'Does'); -- cgit v1.2.3 From 75320beb234e3321e76b04010b292e343cf26f6d Mon Sep 17 00:00:00 2001 From: Mark Date: Wed, 22 Jan 2020 12:16:26 +0000 Subject: Added missing import std.stdio... to make an example compilable. --- d.html.markdown | 1 + 1 file changed, 1 insertion(+) diff --git a/d.html.markdown b/d.html.markdown index d2a57cae..93c08da2 100644 --- a/d.html.markdown +++ b/d.html.markdown @@ -212,6 +212,7 @@ found in the wonderful `std.algorithm` module! ```d import std.algorithm : map, filter, reduce; import std.range : iota; // builds an end-exclusive range +import std.stdio; void main() { // We want to print the sum of a list of squares of even ints -- cgit v1.2.3 From 51e66185357ec8e7ab6d35d1c74d6f328029eb72 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E8=B0=AD=E4=B9=9D=E9=BC=8E?= <109224573@qq.com> Date: Thu, 23 Jan 2020 10:59:04 +0800 Subject: Update zh-cn/yaml-cn.html.markdown Co-Authored-By: woclass --- zh-cn/yaml-cn.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/zh-cn/yaml-cn.html.markdown b/zh-cn/yaml-cn.html.markdown index ebb3aa62..5a7e45f4 100644 --- a/zh-cn/yaml-cn.html.markdown +++ b/zh-cn/yaml-cn.html.markdown @@ -16,7 +16,7 @@ YAML 根本不容许文字制表符。 ```yaml ---- # document start +--- # 文档开头 # YAML 中的注解看起来像这样。 -- cgit v1.2.3 From 0f6291c0b2622d66edebd3366ba4362998f6a055 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E8=B0=AD=E4=B9=9D=E9=BC=8E?= <109224573@qq.com> Date: Thu, 23 Jan 2020 11:00:44 +0800 Subject: Update yaml-cn.html.markdown --- zh-cn/yaml-cn.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/zh-cn/yaml-cn.html.markdown b/zh-cn/yaml-cn.html.markdown index 5a7e45f4..e75fafba 100644 --- a/zh-cn/yaml-cn.html.markdown +++ b/zh-cn/yaml-cn.html.markdown @@ -178,7 +178,7 @@ set2: item2: null item3: null -... # document end +... # 文档结束 ``` ### 更多资源 -- cgit v1.2.3 From 96eddee475db3e9c58b7b24694d3cb2fb4a42a14 Mon Sep 17 00:00:00 2001 From: David Hari Date: Fri, 24 Jan 2020 11:51:52 +1100 Subject: Made some improvements MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit • Under Simple syntax, it referred to a unary message as “a single string”. I think it would be clearer and more accurate to describe it as “a single symbol”. Calling it a string may leave people confused with actual strings (i.e. instance of String class). Furthermore, message selectors are actually Symbol instances. • Fixed the formatting of the bullet-point list of messages. • Fixed the formatting of the example code, and set highlighting to smalltalk language. • Under Assignment, many of the examples are actually access and assignment. You could simplify the list down to just the first 6 (i.e. up to and including x := Object new). The rest can go in a section further down which is about interesting base access methods. Even the Object new example isn’t really necessary, but it helps to show that assigning objects is no different from assigning literals. --- smalltalk.html.markdown | 92 ++++++++++++++++++++++++------------------------- 1 file changed, 45 insertions(+), 47 deletions(-) diff --git a/smalltalk.html.markdown b/smalltalk.html.markdown index ae7ecb0e..faf826f3 100644 --- a/smalltalk.html.markdown +++ b/smalltalk.html.markdown @@ -30,7 +30,7 @@ The most basic operation is to send a message to an object `anObject aMessage` There are three sorts of messages -- unary - a single string that may be several words conjoined in what we call camelcase form, with no arguments. For example 'size', 'reverseBytes', 'convertToLargerFormatPixels' +- unary - a single symbol that may be several words conjoined in what we call camelcase form, with no arguments. For example 'size', 'reverseBytes', 'convertToLargerFormatPixels' - binary - a small set of symbols of the sort often used for arithmetic operations in most languages, requiring a single argument. For example '+', '//', '@'. We do not use traditional arithmetic precedence, something to keep an eye on. - keyword - the general form where multiple arguments can be passed. As with the unary form we use camelcase to join words together but arguments are inserted in the midst of the message with colons used to separate them lexically. For example 'setTemperature:', 'at:put:', 'drawFrom:to:lineWidth:fillColor:' @@ -38,21 +38,23 @@ There are three sorts of messages `result := myObject doSomethingWith: thatObject` We are sending the message 'doSomethingWith:' to myObject. This happens to be a message that has a single argument but that's not important yet. 'myObject' is a 'MyExampleClass' instance so the system looks at the list of messages understood by MyExampleClass + - beClever - doWierdThing: - doSomethingWith In searching we see what initially looks like a match - but no, it lacks the final colon. So we find the super class of MyExampleClass - BigExampleClass. Which has a list of known messages of its own + - beClever - doSomethingWith: - buildCastleInAir - annoyUserByDoing: -We find a proper exact match and start to execute the code -``` +We find a proper exact match and start to execute the code: + +```smalltalk doSomethingWith: argumentObject -"A comment about what this code is meant to do and any known limitations, problems, where it might be further documented etc" -self size > 4 ifTrue: [^argumentObject sizeRelatingTo: self]. + self size > 4 ifTrue: [^argumentObject sizeRelatingTo: self]. ``` Everything here except the `^` involves sending more messages. Event the `ifTrue:` that you might think is a language control structure is just Smalltalk code. @@ -94,7 +96,7 @@ Taken from [Smalltalk Cheatsheet](http://www.angelfire.com/tx4/cus/notes/smallta `"Period (.) is the statement separator. Not required on last line of a method"` #### Transcript: -``` +```smalltalk Transcript clear. "clear to transcript window" Transcript show: 'Hello World'. "output string in transcript window" Transcript nextPutAll: 'Hello World'. "output string in transcript window" @@ -108,26 +110,17 @@ Transcript endEntry. "flush the output buffer" ``` #### Assignment: -``` +```smalltalk | x y | x _ 4. "assignment (Squeak) <-" x := 5. "assignment" x := y := z := 6. "compound assignment" x := (y := 6) + 1. x := Object new. "bind to allocated instance of a class" -x := 123 class. "discover the object class" -x := Integer superclass. "discover the superclass of a class" -x := Object allInstances. "get an array of all instances of a class" -x := Integer allSuperclasses. "get all superclasses of a class" -x := 1.2 hash. "hash value for object" -y := x copy. "copy object" -y := x shallowCopy. "copy object (not overridden)" -y := x deepCopy. "copy object and instance vars" -y := x veryDeepCopy. "complete tree copy using a dictionary" ``` #### Constants: -``` +```smalltalk | b | b := true. "true constant" b := false. "false constant" @@ -147,7 +140,7 @@ x := #('abc' 2 $a). "mixing of types allowed" ``` #### Booleans: -``` +```smalltalk | b x y | x := 1. y := 2. b := (x = y). "equals" @@ -185,7 +178,7 @@ b := $A isLowercase. "test if lower case character" ``` #### Arithmetic expressions: -``` +```smalltalk | x | x := 6 + 3. "addition" x := 6 - 3. "subtraction" @@ -241,7 +234,7 @@ x := 100 atRandom. "quick random number" ``` #### Bitwise Manipulation: -``` +```smalltalk | b x | x := 16rFF bitAnd: 16r0F. "and bits" x := 16rF0 bitOr: 16r0F. "or bits" @@ -257,7 +250,7 @@ b := 16rFF noMask: 16r0F. "test if all bits set in mask clear in recei ``` #### Conversion: -``` +```smalltalk | x | x := 3.99 asInteger. "convert number to integer (truncates in Squeak)" x := 3.99 asFraction. "convert number to fraction" @@ -281,7 +274,7 @@ x := 15 storeStringBase: 16. - `^`expression terminates block & method (exits all nested blocks) - blocks intended for long term storage should not contain `^` -``` +```smalltalk | x y z | x := [ y := 1. z := 2. ]. x value. "simple block usage" x := [ :argOne :argTwo | argOne, ' and ' , argTwo.]. "set up block with argument passing" @@ -304,7 +297,7 @@ Transcript show: (x value: 'First' value: 'Second'); cr. "use block with argu - private (methods private to class) - instance-creation (class methods for creating instance) -``` +```smalltalk | x | x := 2 sqrt. "unary message" x := 2 raisedTo: 10. "keyword message" @@ -319,7 +312,7 @@ x := 3 + 2; * 100. "result=300. Sends message to same ``` #### Conditional Statements: -``` +```smalltalk | x | x > 10 ifTrue: [Transcript show: 'ifTrue'; cr]. "if then" x > 10 ifFalse: [Transcript show: 'ifFalse'; cr]. "if else" @@ -359,7 +352,7 @@ result := (switch at: $B) value. ``` #### Iteration statements: -``` +```smalltalk | x y | x := 4. y := 1. [x > 0] whileTrue: [x := x - 1. y := y * 2]. "while true loop" @@ -371,7 +364,7 @@ x timesRepeat: [y := y * 2]. "times repeat loop (i := 1 to x ``` #### Character: -``` +```smalltalk | x y | x := $A. "character assignment" y := x isLowercase. "test if lower case" @@ -391,7 +384,7 @@ y := $A max: $B. ``` #### Symbol: -``` +```smalltalk | b x y | x := #Hello. "symbol assignment" y := 'String', 'Concatenation'. "symbol concatenation (result is string)" @@ -413,7 +406,7 @@ y := x asSet. "convert symbol to set collect ``` #### String: -``` +```smalltalk | b x y | x := 'This is a string'. "string assignment" x := 'String', 'Concatenation'. "string concatenation" @@ -447,7 +440,7 @@ Fixed length collection - ByteArray: Array limited to byte elements (0-255) - WordArray: Array limited to word elements (0-2^32) -``` +```smalltalk | b x y sum max | x := #(4 3 2 1). "constant array" x := Array with: 5 with: 4 with: 3 with: 2. "create array with up to 4 elements" @@ -490,7 +483,7 @@ y := x asSet. "convert to set collection" #### OrderedCollection: acts like an expandable array -``` +```smalltalk | b x y sum max | x := OrderedCollection with: 4 with: 3 with: 2 with: 1. "create collection with up to 4 elements" @@ -537,7 +530,7 @@ y := x asSet. "convert to set collection" #### SortedCollection: like OrderedCollection except order of elements determined by sorting criteria -``` +```smalltalk | b x y sum max | x := SortedCollection with: 4 with: 3 with: 2 with: 1. "create collection with up to 4 elements" @@ -583,7 +576,7 @@ y := x asSet. "convert to set collection" #### Bag: like OrderedCollection except elements are in no particular order -``` +```smalltalk | b x y sum max | x := Bag with: 4 with: 3 with: 2 with: 1. "create collection with up to 4 elements" x := Bag new. "allocate collection" @@ -619,7 +612,7 @@ like Bag except duplicates not allowed #### IdentitySet: uses identity test (== rather than =) -``` +```smalltalk | b x y sum max | x := Set with: 4 with: 3 with: 2 with: 1. "create collection with up to 4 elements" x := Set new. "allocate collection" @@ -649,7 +642,7 @@ y := x asSet. "convert to set collection" ``` #### Interval: -``` +```smalltalk | b x y sum max | x := Interval from: 5 to: 10. "create interval object" x := 5 to: 10. @@ -679,7 +672,7 @@ y := x asSet. "convert to set collection" ``` #### Associations: -``` +```smalltalk | x y | x := #myVar->'hello'. y := x key. @@ -690,7 +683,7 @@ y := x value. #### IdentityDictionary: uses identity test (== rather than =) -``` +```smalltalk | b x y | x := Dictionary new. "allocate collection" x add: #a->4; @@ -757,7 +750,7 @@ Smalltalk removeKey: #CMRDictionary ifAbsent: []. "remove user dictionary fr ``` #### Internal Stream: -``` +```smalltalk | b x ios | ios := ReadStream on: 'Hello read stream'. ios := ReadStream on: 'Hello read stream' from: 1 to: 5. @@ -785,7 +778,7 @@ b := ios atEnd. ``` #### FileStream: -``` +```smalltalk | b x ios | ios := FileStream newFileNamed: 'ios.txt'. ios nextPut: $H; cr. @@ -805,7 +798,7 @@ ios close. ``` #### Date: -``` +```smalltalk | x y | x := Date today. "create date for today" x := Date dateAndTimeNow. "create date from current time/date" @@ -839,7 +832,7 @@ b := (x <= Date today). "comparison" ``` #### Time: -``` +```smalltalk | x y | x := Time now. "create time from current time" x := Time dateAndTimeNow. "create time from current time/date" @@ -859,7 +852,7 @@ b := (x <= Time now). "comparison" ``` #### Point: -``` +```smalltalk | x y | x := 200@100. "obtain a new point" y := x x. "x coordinate" @@ -884,12 +877,12 @@ x := 20@5 dotProduct: 10@2. "sum of product (x1*x2 + y1*y2)" ``` #### Rectangle: -``` +```smalltalk Rectangle fromUser. ``` #### Pen: -``` +```smalltalk | myPen | Display restoreAfter: [ Display fillWhite. @@ -917,7 +910,7 @@ Display height. "get display height" ``` #### Dynamic Message Calling/Compiling: -``` +```smalltalk | receiver message result argument keyword1 keyword2 argument1 argument2 | "unary message" @@ -957,7 +950,7 @@ result := (Message ``` #### Class/Meta-Class: -``` +```smalltalk | b x | x := String name. "class name" x := String category. "organization category" @@ -990,7 +983,7 @@ Object withAllSubclasses size. "get total number of class entries" ``` #### Debugging: -``` +```smalltalk | a b x | x yourself. "returns receiver" String browse. "browse specified class" @@ -1013,8 +1006,13 @@ Transcript show: a, b; cr. ``` #### Miscellaneous -``` +```smalltalk | x | +x := 1.2 hash. "hash value for object" +y := x copy. "copy object" +y := x shallowCopy. "copy object (not overridden)" +y := x deepCopy. "copy object and instance vars" +y := x veryDeepCopy. "complete tree copy using a dictionary" "Smalltalk condenseChanges." "compress the change file" x := FillInTheBlank request: 'Prompt Me'. "prompt user for input" Utilities openCommandKeyHelp -- cgit v1.2.3 From d8ac6f4707191e7b8d76deda90f840cfd15bf457 Mon Sep 17 00:00:00 2001 From: Harry Moreno Date: Thu, 23 Jan 2020 19:57:30 -0500 Subject: update broken link --- kdb+.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kdb+.html.markdown b/kdb+.html.markdown index 027b6571..680c01c1 100644 --- a/kdb+.html.markdown +++ b/kdb+.html.markdown @@ -771,6 +771,6 @@ select from splayed / (the columns are read from disk on request) * [*q for mortals* q language tutorial](http://code.kx.com/q4m3/) * [*Introduction to Kdb+* on disk data tutorial](http://code.kx.com/q4m3/14_Introduction_to_Kdb+/) -* [q language reference](http://code.kx.com/q/ref/card/) +* [q language reference](https://code.kx.com/q/ref/) * [Online training courses](http://training.aquaq.co.uk/) * [TorQ production framework](https://github.com/AquaQAnalytics/TorQ) -- cgit v1.2.3 From d8516eed650dafc4eadb5db9a4411e0dfc0c73cb Mon Sep 17 00:00:00 2001 From: Divay Prakash Date: Fri, 24 Jan 2020 19:28:45 +0530 Subject: Update powershell-cn.html.markdown Add lang code --- zh-cn/powershell-cn.html.markdown | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/zh-cn/powershell-cn.html.markdown b/zh-cn/powershell-cn.html.markdown index ad5d50d3..6ab34e9f 100644 --- a/zh-cn/powershell-cn.html.markdown +++ b/zh-cn/powershell-cn.html.markdown @@ -5,7 +5,8 @@ contributors: - ["Wouter Van Schandevijl", "https://github.com/laoujin"] translators: - ["Feng Gao", "https://github.com/gaufung"] -filename: LearnPowershell.ps1 +filename: LearnPowershell-cn.ps1 +lang: zh-cn --- PowerShell 是 Windows 平台下的脚本语言同时也是配置管理框架，它是建立在微软 .Net Framework 之上，Windows 7 以及之后版本都内置 Poweshell。下面的示例中都是 PoweShell 脚本的一部分或者直接能够在 Shell 交互窗口中执行。 -- cgit v1.2.3 From ccf57b418ed50a10a02f823308d53d4eb6c44696 Mon Sep 17 00:00:00 2001 From: Divay Prakash Date: Fri, 24 Jan 2020 20:22:50 +0530 Subject: Update ansible.html.markdown --- ansible.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ansible.html.markdown b/ansible.html.markdown index fc656e30..e4c2615d 100644 --- a/ansible.html.markdown +++ b/ansible.html.markdown @@ -303,7 +303,7 @@ Role can be included in your playbook (executed via your playbook). ``` #### For remaining examples we would use additional repository -This example installs ansible in `virtualenv` so it is independent from a system. +This example installs ansible in `virtualenv` so it is independent from the system. You need to initialize it into your shell-context with the `source environment.sh` command. -- cgit v1.2.3 From 4ac076c8f289034e670d1507158324cc0334cddd Mon Sep 17 00:00:00 2001 From: Philippe Coval Date: Fri, 25 Oct 2019 11:33:09 +0200 Subject: [ansible/en]: Fix URL link Forwarded: https://github.com/adambard/learnxinyminutes-docs/pull/ Change-Id: Ic41e20f44f7e7aeab1811d8d48964c5d57c335eb Signed-off-by: Philippe Coval --- ansible.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ansible.html.markdown b/ansible.html.markdown index 28da618c..30dfba13 100644 --- a/ansible.html.markdown +++ b/ansible.html.markdown @@ -307,7 +307,7 @@ This example installs ansible in `virtualenv` so it is independent from the syst You need to initialize it into your shell-context with the `source environment.sh` command. -We are going to use this repository with examples: [https://github.com/sirkubax/ansible-for-learnXinYminutes]() +We are going to use this repository with examples: [https://github.com/sirkubax/ansible-for-learnXinYminutes](https://github.com/sirkubax/ansible-for-learnXinYminutes) ```bash $ # The following example contains a shell-prompt to indicate the venv and relative path -- cgit v1.2.3 From 2321097fadd30ae0c09cc224a3e0260cd3c9a842 Mon Sep 17 00:00:00 2001 From: Maxime Guerreiro Date: Sat, 25 Jan 2020 22:44:18 +0000 Subject: [elixir/en] Use https links --- elixir.html.markdown | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/elixir.html.markdown b/elixir.html.markdown index 7af29202..0b717ca6 100644 --- a/elixir.html.markdown +++ b/elixir.html.markdown @@ -1,7 +1,7 @@ --- language: elixir contributors: - - ["Joao Marques", "http://github.com/mrshankly"] + - ["Joao Marques", "https://github.com/mrshankly"] - ["Dzianis Dashkevich", "https://github.com/dskecse"] - ["Ryan Plant", "https://github.com/ryanplant-au"] - ["Ev Bogdanov", "https://github.com/evbogdanov"] @@ -451,9 +451,9 @@ Agent.update(my_agent, fn colors -> ["blue" | colors] end) ## References -* [Getting started guide](http://elixir-lang.org/getting-started/introduction.html) from the [Elixir website](http://elixir-lang.org) +* [Getting started guide](https://elixir-lang.org/getting-started/introduction.html) from the [Elixir website](https://elixir-lang.org) * [Elixir Documentation](https://elixir-lang.org/docs.html) * ["Programming Elixir"](https://pragprog.com/book/elixir/programming-elixir) by Dave Thomas -* [Elixir Cheat Sheet](http://media.pragprog.com/titles/elixir/ElixirCheat.pdf) -* ["Learn You Some Erlang for Great Good!"](http://learnyousomeerlang.com/) by Fred Hebert +* [Elixir Cheat Sheet](https://media.pragprog.com/titles/elixir/ElixirCheat.pdf) +* ["Learn You Some Erlang for Great Good!"](https://learnyousomeerlang.com/) by Fred Hebert * ["Programming Erlang: Software for a Concurrent World"](https://pragprog.com/book/jaerlang2/programming-erlang) by Joe Armstrong -- cgit v1.2.3 From 1b01d8c03f1fb68d3f0f2270c9ec1bbeab949f25 Mon Sep 17 00:00:00 2001 From: Andrea Borruso Date: Wed, 29 Jan 2020 08:43:27 +0100 Subject: piccola correzione di testo --- it-it/bash-it.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/it-it/bash-it.html.markdown b/it-it/bash-it.html.markdown index 099cc681..cfe58f30 100644 --- a/it-it/bash-it.html.markdown +++ b/it-it/bash-it.html.markdown @@ -63,7 +63,7 @@ echo ${Variabile} # Sotto ci sono altri esempi che analizzano l'uso dell'espansione dei parametri. # Sostituzione di stringhe nelle variabili -echo ${Variabile/Una/A} +echo ${Variabile/Una/La} # Questo sostituirà la prima occorrenza di "Una" con "La" # Sottostringa di una variabile -- cgit v1.2.3 From e157a92b38fbc89bd9e9e023a2c36f3670a5553f Mon Sep 17 00:00:00 2001 From: Bob Date: Thu, 30 Jan 2020 17:19:48 +0800 Subject: Added zh-tw translation to Dart --- zh-tw/dart-tw.html.markdown | 566 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 566 insertions(+) create mode 100644 zh-tw/dart-tw.html.markdown diff --git a/zh-tw/dart-tw.html.markdown b/zh-tw/dart-tw.html.markdown new file mode 100644 index 00000000..5a9241c2 --- /dev/null +++ b/zh-tw/dart-tw.html.markdown @@ -0,0 +1,566 @@ +--- +language: dart +lang: zh-tw +filename: learndart-tw.dart +contributors: + - ["Joao Pedrosa", "https://github.com/jpedrosa/"] +translators: + - ["Bob Lu", "https://github.com/LuPoYi/"] +--- + +Dart 是程式語言領域的新人。 +它借鑒了許多其他主流語言，並且不會偏離它的兄弟語言 JavaScript 太多。 +就像 JavaScript 一樣，Dart 的目標是提供良好的瀏覽器整合性。 + +Dart 最有爭議的特性必然是它的可選類型。 + +```javascript +import "dart:collection"; +import "dart:math" as DM; + +// 歡迎進入15分鐘的 Dart 學習。 http://www.dartlang.org/ +// 這是一個可實際執行的範例。你可以用 Dart 執行它 +// 或者線上執行! 可以把程式碼複製/貼上到這個網站。 http://try.dartlang.org/ + +// 函數宣告和方法宣告看起來一樣。 +// 函數宣告可以是巢狀的。宣告使用這種 name() {} 的形式， +// 或者 name() => 單行表示式; 的形式。 +// 右箭頭的宣告形式會直接地返回表示式的結果。 +example1() { + example1nested1() { + example1nested2() => print("Example1 nested 1 nested 2"); + example1nested2(); + } + example1nested1(); +} + +// 匿名函數沒有函數名。 +example2() { + example2nested1(fn) { + fn(); + } + example2nested1(() => print("Example2 nested 1")); +} + +// 當宣告函數類型的參數的時候，宣告中可以包含 +// 函數參數需要的參數，指定所需的參數名即可。 +example3() { + example3nested1(fn(informSomething)) { + fn("Example3 nested 1"); + } + example3planB(fn) { // 或者不宣告函數參數的參數 + fn("Example3 plan B"); + } + example3nested1((s) => print(s)); + example3planB((s) => print(s)); +} + +// 函數有可以訪問到外層變數的閉包。 +var example4Something = "Example4 nested 1"; +example4() { + example4nested1(fn(informSomething)) { + fn(example4Something); + } + example4nested1((s) => print(s)); +} + +// 下面這個包含 sayIt 方法的類別宣告，同樣有一個可以訪問外層變數的閉包， +// 就像前面的函數一樣。 +var example5method = "Example5 sayIt"; +class Example5Class { + sayIt() { + print(example5method); + } +} +example5() { + // 創建一個 Example5Class 類的匿名實例， + // 並呼叫它的 sayIt 方法。 + new Example5Class().sayIt(); +} + +// 類別的宣告使用這種形式 class name { [classBody] }. +// classBody 中可以包含實例方法和變數， +// 還可以包含類別方法和變數。 +class Example6Class { + var example6InstanceVariable = "Example6 instance variable"; + sayIt() { + print(example6InstanceVariable); + } +} +example6() { + new Example6Class().sayIt(); +} + +// 類別方法和變數使用 static 宣告。 +class Example7Class { + static var example7ClassVariable = "Example7 class variable"; + static sayItFromClass() { + print(example7ClassVariable); + } + sayItFromInstance() { + print(example7ClassVariable); + } +} +example7() { + Example7Class.sayItFromClass(); + new Example7Class().sayItFromInstance(); +} + +// 定數非常方便，但是對於在函數/方法的外層的定數有一個限制， +// 類別的外層或外面的定數必須是常數。 +// 字串和數字預設是常數。 +// 但是 array 和 map 不是。他們需要用 "const" 宣告為常數。 +var example8Array = const ["Example8 const array"], + example8Map = const {"someKey": "Example8 const map"}; +example8() { + print(example8Array[0]); + print(example8Map["someKey"]); +} + +// Dart 中的迴圈使用標準的 for () {} 或 while () {} 的形式， +// 以及更加現代的 for (.. in ..) {} 的形式, 或者 +// 以 forEach 開頭並具有許多特性支援函數回呼的形式。 +var example9Array = const ["a", "b"]; +example9() { + for (var i = 0; i < example9Array.length; i++) { + print("Example9 for loop '${example9Array[i]}'"); + } + var i = 0; + while (i < example9Array.length) { + print("Example9 while loop '${example9Array[i]}'"); + i++; + } + for (var e in example9Array) { + print("Example9 for-in loop '${e}'"); + } + example9Array.forEach((e) => print("Example9 forEach loop '${e}'")); +} + +// 透過迴圈遍歷字串中的每個字元或者取出其子字串。 +var example10S = "ab"; +example10() { + for (var i = 0; i < example10S.length; i++) { + print("Example10 String character loop '${example10S[i]}'"); + } + for (var i = 0; i < example10S.length; i++) { + print("Example10 substring loop '${example10S.substring(i, i + 1)}'"); + } +} + +// 支援兩種數字格式 int 和 double。 +example11() { + var i = 1 + 320, d = 3.2 + 0.01; + print("Example11 int ${i}"); + print("Example11 double ${d}"); +} + +// DateTime 提供了日期/時間的方法。 +example12() { + var now = new DateTime.now(); + print("Example12 now '${now}'"); + now = now.add(new Duration(days: 1)); + print("Example12 tomorrow '${now}'"); +} + +// 支援正規表達式。 +example13() { + var s1 = "some string", s2 = "some", re = new RegExp("^s.+?g\$"); + match(s) { + if (re.hasMatch(s)) { + print("Example13 regexp matches '${s}'"); + } else { + print("Example13 regexp doesn't match '${s}'"); + } + } + match(s1); + match(s2); +} + +// 布林運算式支持隱式轉換以及動態類型 +example14() { + var a = true; + if (a) { + print("Example14 true, a is $a"); + } + a = null; + if (a) { + print("Example14 true, a is $a"); + } else { + print("Example14 false, a is $a"); // 執行到這裡 + } + +// 動態類型的null可以轉換成bool型 + var b; // b是動態類型 + b = "abc"; + try { + if (b) { + print("Example14 true, b is $b"); + } else { + print("Example14 false, b is $b"); + } + } catch (e) { + print("Example14 error, b is $b"); // 這段程式碼可以執行但是會報錯 + } + b = null; + if (b) { + print("Example14 true, b is $b"); + } else { + print("Example14 false, b is $b"); // 執行到這裡 + } + + // 靜態類型的null不能轉換成bool型 + var c = "abc"; + c = null; + // 編譯出錯 + // if (c) { + // print("Example14 true, c is $c"); + // } else { + // print("Example14 false, c is $c"); + // } +} + +// try/catch/finally 和 throw 語句用於例外處理。 +// throw 語句可以使用任何物件作為參數。 +example15() { + try { + try { + throw "Some unexpected error."; + } catch (e) { + print("Example15 an exception: '${e}'"); + throw e; // Re-throw + } + } catch (e) { + print("Example15 catch exception being re-thrown: '${e}'"); + } finally { + print("Example15 Still run finally"); + } +} + +// 想要有效地動態創建長字串， +// 應該使用 StringBuffer。或者 join 一個字串的陣列。 +example16() { + var sb = new StringBuffer(), a = ["a", "b", "c", "d"], e; + for (e in a) { sb.write(e); } + print("Example16 dynamic string created with " + "StringBuffer '${sb.toString()}'"); + print("Example16 join string array '${a.join()}'"); +} + +// 字串連接只需讓相鄰的字串相連， +// 不需要額外的操作運算符號。 +example17() { + print("Example17 " + "concatenate " + "strings " + "just like that"); +} + +// 字串使用單引號或雙引號做分隔，二者並沒有實際的差異。 +// 這種靈活性可以很好地避免內容中需要轉義換行的情況。 +// 例如，字串內容裡的 HTML 屬性使用了雙引號。 +example18() { + print('Example18 ' + "Don't can't I'm Etc" + ''); +} + +// 用三個單引號或三個雙引號表示的字串 +// 可以跨越多行，並且包含換行。 +example19() { + print('''Example19 +Example19 Don't can't I'm Etc +Example19 '''); +} + +// 字串可以使用 $ 符號插入內容。 +// 使用 $ { [expression] } 的形式，表示式的值會被插入到字串中。 +// $ 跟著一個變數名會插入變數的值。 +// 如果要在字符串中插入 $ ，可以使用 \$ 的轉義形式取代。 +example20() { + var s1 = "'\${s}'", s2 = "'\$s'"; + print("Example20 \$ interpolation ${s1} or $s2 works."); +} + +// 可選類型允許作為 API 的標註，並且可以輔助 IDE， +// 這樣 IDE 可以更好地提供重構、自動完成和錯誤檢測功能。 +// 目前為止我們還沒有宣告任何類型，並且程式可以執行。 +// 事實上，類型在執行時會被忽略。 +// 類型甚至可以是錯的，並且程式依然可以執行， +// 好像和類型完全無關一樣。 +// 有一個執行時參數可以讓程式進入檢查模式，它會在執行時檢查類型錯誤。 +// 這在開發時很有用，但是由於增加了額外的檢查會使程式變慢， +// 因此應該避免在部署時使用。 +class Example21 { + List _names; + Example21() { + _names = ["a", "b"]; + } + List get names => _names; + set names(List list) { + _names = list; + } + int get length => _names.length; + void add(String name) { + _names.add(name); + } +} + +void example21() { + Example21 o = new Example21(); + o.add("c"); + print("Example21 names '${o.names}' and length '${o.length}'"); + o.names = ["d", "e"]; + print("Example21 names '${o.names}' and length '${o.length}'"); +} + +// 類型的繼承形式是 class name extends AnotherClassName {} 。 +class Example22A { + var _name = "Some Name!"; + get name => _name; +} +class Example22B extends Example22A {} +example22() { + var o = new Example22B(); + print("Example22 class inheritance '${o.name}'"); +} + +// 類型也可以使用 mixin 的形式 ： +// class name extends SomeClass with AnotherClassName {}. +// 必需繼承某個類型才能 mixin 另一個類型。 +// 當前 mixin 的模板類型不能有建構子。 +// Mixin 主要是用來和輔助的類型共享方法的， +// 這樣單一繼承就不會影響程式碼重覆使用。 +// Mixin 宣告在類型定義的 "with" 後面。 +class Example23A {} +class Example23Utils { + addTwo(n1, n2) { + return n1 + n2; + } +} +class Example23B extends Example23A with Example23Utils { + addThree(n1, n2, n3) { + return addTwo(n1, n2) + n3; + } +} +example23() { + var o = new Example23B(), r1 = o.addThree(1, 2, 3), + r2 = o.addTwo(1, 2); + print("Example23 addThree(1, 2, 3) results in '${r1}'"); + print("Example23 addTwo(1, 2) results in '${r2}'"); +} + +// 類型的建構子和類型名相同，形式為 +// SomeClass() : super() {}, 其中 ": super()" 的部分是可選的， +// 它用來傳遞參數給父類型的建構子。 +class Example24A { + var _value; + Example24A({value: "someValue"}) { + _value = value; + } + get value => _value; +} +class Example24B extends Example24A { + Example24B({value: "someOtherValue"}) : super(value: value); +} +example24() { + var o1 = new Example24B(), + o2 = new Example24B(value: "evenMore"); + print("Example24 calling super during constructor '${o1.value}'"); + print("Example24 calling super during constructor '${o2.value}'"); +} + +// 對於簡單的類型，有一種設置構造函數參數的快捷方式。 +// 只需要使用 this.parameterName 的前綴， +// 它就會把參數設置為同名的實例變數。 +class Example25 { + var value, anotherValue; + Example25({this.value, this.anotherValue}); +} +example25() { + var o = new Example25(value: "a", anotherValue: "b"); + print("Example25 shortcut for constructor '${o.value}' and " + "'${o.anotherValue}'"); +} + +// 可以在大括號 {} 中宣告命名參數。 +// 大括號 {} 中宣告的參數的順序是隨意的。 +// 在中括號 [] 中宣告的參數也是可選的。 +example26() { + var _name, _surname, _email; + setConfig1({name, surname}) { + _name = name; + _surname = surname; + } + setConfig2(name, [surname, email]) { + _name = name; + _surname = surname; + _email = email; + } + setConfig1(surname: "Doe", name: "John"); + print("Example26 name '${_name}', surname '${_surname}', " + "email '${_email}'"); + setConfig2("Mary", "Jane"); + print("Example26 name '${_name}', surname '${_surname}', " + "email '${_email}'"); +} + +// 使用 final 宣告的變數只能被設置一次。 +// 在類型裡面，final 實例變數可以通過常數的建構子參數設置。 +class Example27 { + final color1, color2; + // 更靈活一點的方法是在冒號 : 後面設置 final 實例變數。 + Example27({this.color1, color2}) : color2 = color2; +} +example27() { + final color = "orange", o = new Example27(color1: "lilac", color2: "white"); + print("Example27 color is '${color}'"); + print("Example27 color is '${o.color1}' and '${o.color2}'"); +} + +// 要導入一個函式庫，使用 import "libraryPath" 的形式，或者如果要導入的是 +// 核心庫使用 import "dart:libraryName" 。還有一個稱為 "pub" 的套件管理工具， +// 它使用 import "package:packageName" 的約定形式。 +// 看下這個文件頂部的 import "dart:collection"; 語法。 +// 導入語句必需在其它程式碼宣告之前出現。 IterableBase 來自於 dart:collection 。 +class Example28 extends IterableBase { + var names; + Example28() { + names = ["a", "b"]; + } + get iterator => names.iterator; +} +example28() { + var o = new Example28(); + o.forEach((name) => print("Example28 '${name}'")); +} + +// 對於控制流程，我們有： +// * 必需帶 break 的標準 switch 語法 +// * if-else 和三元運算子 ..?..:.. +// * 閉包和匿名函數 +// * break, continue 和 return 語法 +example29() { + var v = true ? 30 : 60; + switch (v) { + case 30: + print("Example29 switch statement"); + break; + } + if (v < 30) { + } else if (v > 30) { + } else { + print("Example29 if-else statement"); + } + callItForMe(fn()) { + return fn(); + } + rand() { + v = new DM.Random().nextInt(50); + return v; + } + while (true) { + print("Example29 callItForMe(rand) '${callItForMe(rand)}'"); + if (v != 30) { + break; + } else { + continue; + } + // 不會到這裡。 + } +} + +// 解析 int，把 double 轉成 int，或者使用 ~/ 運算符號在除法計算時僅保留整數位。 +// 讓我們也來場猜數遊戲吧。 +example30() { + var gn, + tooHigh = false, + n, + n2 = (2.0).toInt(), + top = int.parse("123") ~/ n2, + bottom = 0; + top = top ~/ 6; + gn = new DM.Random().nextInt(top + 1); // +1 because nextInt top is exclusive + print("Example30 Guess a number between 0 and ${top}"); + guessNumber(i) { + if (n == gn) { + print("Example30 Guessed right! The number is ${gn}"); + } else { + tooHigh = n > gn; + print("Example30 Number ${n} is too " + "${tooHigh ? 'high' : 'low'}. Try again"); + } + return n == gn; + } + + n = (top - bottom) ~/ 2; + while (!guessNumber(n)) { + if (tooHigh) { + top = n - 1; + } else { + bottom = n + 1; + } + n = bottom + ((top - bottom) ~/ 2); + } +} + +// 選填位置參數： +// 參數定義使用方括號 [ ]，傳入參數是選填的。 +example31() { + findVolume31(int length, int breath, [int height]) { + print('length = $length, breath = $breath, height = $height'); + } + + findVolume31(10,20,30); // 可執行 + findVolume31(10,20); // 也可執行 +} + +// 選填命名參數： +// 參數定義使用大括號 { }, 傳入參數是選填的。 +// 必須傳入參數名稱及參數值，並以 : 分隔 +// 大括號的順序沒有差別 +// 這種類型參數可以幫我們避免多個參數傳入時造成混淆。 +example32() { + findVolume32(int length, int breath, {int height}) { + print('length = $length, breath = $breath, height = $height'); + } + + findVolume32(10,20,height:30); // 可執行 & 參數名稱在這邊有傳入 + findVolume32(10,20); // 也可執行 +} + +// 選填預設參數： +// 與選填命名參數相同，此外，我們為此參數定義的預設值 +// 如果沒有傳入值，就使用預設值 +example33() { + findVolume33(int length, int breath, {int height=10}) { + print('length = $length, breath = $breath, height = $height'); + } + + findVolume33(10,20,height:30); // 可執行 + findVolume33(10,20); // 可執行 +} + +// 程式的唯一入口點是 main 函式。 +// 在程式開始執行 main 函式之前，不會執行任何外部程式碼。 +// 這樣有助於更快加載甚至是延遲加載程式啟動時所需要的部分； +main() { + print("Learn Dart in 15 minutes!"); + [ + example1, example2, example3, example4, example5, + example6, example7, example8, example9, example10, + example11, example12, example13, example14, example15, + example16, example17, example18, example19, example20, + example21, example22, example23, example24, example25, + example26, example27, example28, example29, + example30 // 增加此註解可阻止dart formatter把所有項目都換行 + ].forEach((ef) => ef()); +} + +``` + +## 延伸閱讀 + +Dart 有一個綜合性網站。它涵蓋了 API 參考、入門教學、文章以及更多， +還包括一個有用的線上試用 Dart 頁面。 +* [https://www.dartlang.org](https://www.dartlang.org) +* [https://try.dartlang.org](https://try.dartlang.org) -- cgit v1.2.3 From 6e056f93dc12e6811f0f247877e1ba7bd6172803 Mon Sep 17 00:00:00 2001 From: Richard Eng Date: Thu, 30 Jan 2020 07:31:47 -0500 Subject: Update smalltalk.html.markdown --- smalltalk.html.markdown | 1 + 1 file changed, 1 insertion(+) diff --git a/smalltalk.html.markdown b/smalltalk.html.markdown index faf826f3..d6d369cc 100644 --- a/smalltalk.html.markdown +++ b/smalltalk.html.markdown @@ -30,6 +30,7 @@ The most basic operation is to send a message to an object `anObject aMessage` There are three sorts of messages + - unary - a single symbol that may be several words conjoined in what we call camelcase form, with no arguments. For example 'size', 'reverseBytes', 'convertToLargerFormatPixels' - binary - a small set of symbols of the sort often used for arithmetic operations in most languages, requiring a single argument. For example '+', '//', '@'. We do not use traditional arithmetic precedence, something to keep an eye on. - keyword - the general form where multiple arguments can be passed. As with the unary form we use camelcase to join words together but arguments are inserted in the midst of the message with colons used to separate them lexically. For example 'setTemperature:', 'at:put:', 'drawFrom:to:lineWidth:fillColor:' -- cgit v1.2.3 From 043e4984ffa29389e3110a8f277870642df51097 Mon Sep 17 00:00:00 2001 From: caminsha Date: Thu, 30 Jan 2020 17:48:40 +0100 Subject: removed doubled line --- de-de/bc.html.markdown | 1 - 1 file changed, 1 deletion(-) diff --git a/de-de/bc.html.markdown b/de-de/bc.html.markdown index 9aedd93b..e1b51e4f 100644 --- a/de-de/bc.html.markdown +++ b/de-de/bc.html.markdown @@ -29,7 +29,6 @@ obase: definiert die Basis der Ausgabe*/ hour = read() /*Eingabe einer Zahl*/ if(hour < 12) { /*Operatoren sind genau wie in C*/ - print "Guten Morgen\n" /*"print" outputs strings or variables print "Guten Morgen\n" /*"print" Gibt Strings oder Variablen mit einem Komma separiert aus.*/ } else if(hour == 12) { -- cgit v1.2.3 From 42ce472cf95d60bbd1f64ed022c84362dfc3cf6f Mon Sep 17 00:00:00 2001 From: caminsha Date: Thu, 30 Jan 2020 17:49:10 +0100 Subject: =?UTF-8?q?removed=20Wagenr=C3=BCcklauf=20because=20it=20is=20not?= =?UTF-8?q?=20very=20common?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- de-de/bc.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/de-de/bc.html.markdown b/de-de/bc.html.markdown index e1b51e4f..61ae1b79 100644 --- a/de-de/bc.html.markdown +++ b/de-de/bc.html.markdown @@ -37,7 +37,7 @@ if(hour < 12) { /*Operatoren sind genau wie in C*/ Um Escape-Sequenzen klarer zu machen, ist hier eine vereinfachte Liste, welche in bc funktioneren.: \b: Backspace - \c: Wagenrücklauf (carriage return) + \c: carriage return \n: Zeilenumbruch \t: Tab \\: Backslash*/ -- cgit v1.2.3 From f3f32e2d814650db6ce633a73ba99ef0c8ceaef1 Mon Sep 17 00:00:00 2001 From: caminsha Date: Thu, 30 Jan 2020 17:49:48 +0100 Subject: made newlines so that the content is not more than 80 char --- de-de/bc.html.markdown | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/de-de/bc.html.markdown b/de-de/bc.html.markdown index 61ae1b79..3e04f2a7 100644 --- a/de-de/bc.html.markdown +++ b/de-de/bc.html.markdown @@ -44,7 +44,8 @@ if(hour < 12) { /*Operatoren sind genau wie in C*/ } else { /* Standardmässig sind Variablen global. */ thisIsGlobal = 5 - /*Variablen können lokal gemacht werden. Benutze das Schlüsselwort "auto" in einer Funktion.*/ + /*Variablen können lokal gemacht werden. Benutze das Schlüsselwort "auto" + in einer Funktion.*/ } /* Jede Variable hat als Voreinstellung den Wert 0. */ @@ -84,7 +85,8 @@ define x(n) { return n + x } x(3) /*4*/ -print x /*Es stellt sich heraus, dass x ausserhalb der Funktion nicht zugänglich ist.*/ +print x /*Es stellt sich heraus, dass x ausserhalb der Funktion nicht + zugänglich ist.*/ /*Arrays sind äquivalent zu C Arrays.*/ for(i = 0; i <= 3; i++) { a[i] = 1 -- cgit v1.2.3 From de19c7fbe18a1307a1ebcea02d683366c231b133 Mon Sep 17 00:00:00 2001 From: caminsha Date: Thu, 30 Jan 2020 17:50:09 +0100 Subject: added ternary operator --- de-de/bc.html.markdown | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/de-de/bc.html.markdown b/de-de/bc.html.markdown index 3e04f2a7..49a2878d 100644 --- a/de-de/bc.html.markdown +++ b/de-de/bc.html.markdown @@ -54,10 +54,10 @@ num = blankVariable /*num wurde auf 0 gesetzt.*/ /*Wie in C ist nur 0 falsch.*/ if(!num) {print "false\n"} -/*Im Gegensatz zu C hat bc die Operatoren ?: nicht. Zum Beispiel +/*Im Gegensatz zu C hat bc den Ternäroperator ?: nicht. Zum Beispiel führt dieser Codeblok zu einem Fehler: a = (num) ? 1 : 0 -/*Jedoch kann dies simuliert werden:*/ +Jedoch kann dies simuliert werden:*/ a = (num) && (1) || (0) /*&& ist das UND, || ist das ODER*/ /*For-Schleifen*/ -- cgit v1.2.3 From 5e23544d4fc283917063998f0272a33c6c0d364c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?RUSLAN=20L=C3=93PEZ=20CARRO?= Date: Thu, 30 Jan 2020 14:36:48 -0600 Subject: language/docker (#3805) * Related to issue #3631 The docker hello world in english * Related to issue #3631 docker interactive mode * Related to issue #3631 limited script to 80 characters --- docker.html.markdown | 146 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 146 insertions(+) create mode 100644 docker.html.markdown diff --git a/docker.html.markdown b/docker.html.markdown new file mode 100644 index 00000000..24f85247 --- /dev/null +++ b/docker.html.markdown @@ -0,0 +1,146 @@ +--- +language: docker +filename: docker.bat +contributors: + - ["Ruslan López", "http://javapro.org/"] +--- + +``` +:: download, install and run hello-world image +docker run hello-world + +:: if this is the first time you should be able to see the message +:: Unable to find image 'hello-world:latest' locally +:: latest: Pulling from library/hello-world +:: 1b930d010525: Pull complete +:: Digest: sha256:4fe721ccc2e8dc7362278a29dc660d833570ec2682f4e4194f4ee23e415e1064 +:: Status: Downloaded newer image for hello-world:latest +:: +:: Hello from Docker! +:: This message shows that your installation appears to be working correctly. +:: +:: To generate this message, Docker took the following steps: +:: 1. The Docker client contacted the Docker daemon. +:: 2. The Docker daemon pulled the "hello-world" image from the Docker Hub. +:: (amd64) +:: 3. The Docker daemon created a new container from that image which runs the +:: executable that produces the output you are currently reading. +:: 4. The Docker daemon streamed that output to the Docker client, which sent it +:: to your terminal. +:: +:: To try something more ambitious, you can run an Ubuntu container with: +:: $ docker run -it ubuntu bash +:: +:: Share images, automate workflows, and more with a free Docker ID: +:: https://hub.docker.com/ +:: +:: For more examples and ideas, visit: +:: https://docs.docker.com/get-started/ + +:: now lets see currently running images +docker ps +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES + +:: lets see the images we have ran previously +docker ps -a + +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES +:: 4a76281f9c53 hello-world "/hello" 2 minutes ago Exited (0) 2 minutes ago +:: happy_poincare +:: the name part is generated automatically so it probably will be different for you + +:: let's remove our previously generated image +docker rm happy_poincare + +:: lets test if it was really deleted +docker ps -a +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES + +:: specify a custom name for the container +docker run --name test_container hello-world +:: Hello from Docker! +:: This message shows that your installation appears to be working correctly. +:: +:: To generate this message, Docker took the following steps: +:: 1. The Docker client contacted the Docker daemon. +:: 2. The Docker daemon pulled the "hello-world" image from the Docker Hub. +:: (amd64) +:: 3. The Docker daemon created a new container from that image which runs the +:: executable that produces the output you are currently reading. +:: 4. The Docker daemon streamed that output to the Docker client, which sent it +:: to your terminal. +:: +:: To try something more ambitious, you can run an Ubuntu container with: +:: $ docker run -it ubuntu bash +:: +:: Share images, automate workflows, and more with a free Docker ID: +:: https://hub.docker.com/ +:: +:: For more examples and ideas, visit: +:: https://docs.docker.com/get-started/ + +docker ps -a +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES +:: d345fe1a4f41 hello-world "/hello" About a minute ago Exited (0) About a minute ago +:: test_container +:: as you can see the name is now what we have specified + +:: retireve logs from a named container +docker logs test_container +:: Hello from Docker! +:: This message shows that your installation appears to be working correctly. +:: +:: To generate this message, Docker took the following steps: +:: 1. The Docker client contacted the Docker daemon. +:: 2. The Docker daemon pulled the "hello-world" image from the Docker Hub. +:: (amd64) +:: 3. The Docker daemon created a new container from that image which runs the +:: executable that produces the output you are currently reading. +:: 4. The Docker daemon streamed that output to the Docker client, which sent it +:: to your terminal. +:: +:: To try something more ambitious, you can run an Ubuntu container with: +:: $ docker run -it ubuntu bash +:: +:: Share images, automate workflows, and more with a free Docker ID: +:: https://hub.docker.com/ +:: +:: For more examples and ideas, visit: +:: https://docs.docker.com/get-started/ + +docker rm test_container + +docker run ubuntu +:: Unable to find image 'ubuntu:latest' locally +:: latest: Pulling from library/ubuntu +:: 2746a4a261c9: Pull complete +:: 4c1d20cdee96: Pull complete 0d3160e1d0de: Pull complete c8e37668deea: Pull complete Digest: sha256:250cc6f3f3ffc5cdaa9d8f4946ac79821aafb4d3afc93928f0de9336eba21aa4 +:: Status: Downloaded newer image for ubuntu:latest + +docker ps -a +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES +:: c19e9e5b000a ubuntu "/bin/bash" 5 seconds ago Exited (0) 4 seconds ago +:: relaxed_nobel + +:: running a container in an interactive mode +docker run -it ubuntu +:: root@e2cac48323d2:/# uname +:: Linux +:: root@e2cac48323d2:/# exit +:: exit + +docker rm relaxed_nobel + +docker ps -a +:: CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS +:: NAMES +:: e2cac48323d2 ubuntu "/bin/bash" 2 minutes ago Exited (0) About a minute ago +:: nifty_goldwasser + +docker rm nifty_goldwasser +``` \ No newline at end of file -- cgit v1.2.3 From a7242df7d7f49ee2a7440a5a10f203d64e481f24 Mon Sep 17 00:00:00 2001 From: Michael Graf Date: Thu, 30 Jan 2020 15:29:06 -0800 Subject: go/en: add type switch and multiple cases --- go.html.markdown | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/go.html.markdown b/go.html.markdown index 4fc155b5..49f1ade4 100644 --- a/go.html.markdown +++ b/go.html.markdown @@ -12,6 +12,7 @@ contributors: - ["Alexej Friesen", "https://github.com/heyalexej"] - ["Clayton Walker", "https://github.com/cwalk"] - ["Leonid Shevtsov", "https://github.com/leonid-shevtsov"] + - ["Michael Graf", "https://github.com/maerf0x0"] --- Go was created out of the need to get work done. It's not the latest trend @@ -196,7 +197,7 @@ func learnFlowControl() { x := 42.0 switch x { case 0: - case 1: + case 1, 2: // Can have multiple matches on one case case 42: // Cases don't "fall through". /* @@ -208,6 +209,19 @@ func learnFlowControl() { default: // Default case is optional. } + + // Type switch allows switching on the type of something instead of value + var data interface{} + data = "" + switch c := data.(type) { + case string: + fmt.Println(c, "is a string") + case int64: + fmt.Printf("%d is an int64\n", c) + default: + // all other cases + } + // Like if, for doesn't use parens either. // Variables declared in for and if are local to their scope. for x := 0; x < 3; x++ { // ++ is a statement. -- cgit v1.2.3 From bb97b7c3e4025ed92d23e72335efc3e685ce3fef Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D9=81=D8=A7=D8=B1=D8=B3?= Date: Thu, 30 Jan 2020 20:24:47 -0500 Subject: Fixed Typo and added a few examples --- toml.html.markdown | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/toml.html.markdown b/toml.html.markdown index 385a2437..4c76ee91 100755 --- a/toml.html.markdown +++ b/toml.html.markdown @@ -117,7 +117,7 @@ date4 = 1979-05-27 # without offset or time array1 = [ 1, 2, 3 ] array2 = [ "Commas", "are", "delimiters" ] -array3 = [ "Don't mixed", "different", "types" ] +array3 = [ "Don't mix", "different", "types" ] array4 = [ [ 1.2, 2.4 ], ["all", 'strings', """are the same""", '''type'''] ] array5 = [ "Whitespace", "is", "ignored" @@ -171,6 +171,9 @@ c = 1 [a] d = 2 +# Will generate the following in JSON: +# { "a": {"b": {"c": 1}, "d": 2 } } + # You cannot define any key or table more than once. Doing so is invalid. # DO NOT DO THIS @@ -221,6 +224,24 @@ name = "Nail" sku = 284758393 color = "gray" +# JSON-land styled structure: +```json +{ + "products": [ + { + "name": "array of table", + "sku": 7385594937, + "emptyTableAreAllowed": true + }, + {}, + { + "name": "Nail", + "sku": 284758393, + "color": "gray" + } + ] +} +``` # You can create nested arrays of tables as well. Each double-bracketed # sub-table will belong to the nearest table element above it. @@ -247,7 +268,7 @@ color = "gray" note = "I am an array item in banana fruit's table/map" ``` -In JSON land, this code will be: +# In JSON land, this code will be: ```json { -- cgit v1.2.3 From e08467e87257b718ec687e8d58d72172d660f070 Mon Sep 17 00:00:00 2001 From: caminsha Date: Fri, 31 Jan 2020 03:41:40 +0100 Subject: Fixed some small typos --- de-de/css-de.html.markdown | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/de-de/css-de.html.markdown b/de-de/css-de.html.markdown index c31e73d2..da706e91 100644 --- a/de-de/css-de.html.markdown +++ b/de-de/css-de.html.markdown @@ -27,7 +27,7 @@ In diesem Artikel wird am meisten auf generelle Hinweise und die Syntax geachtet ####################*/ /* Eigentlich ist das grundlegende CSS-Statement sehr simpel */ -selektor { eigenschaft: wert; /* mehr eigenschaften...*/ } +selektor { eigenschaft: wert; /* mehr Eigenschaften...*/ } /* Der Selektor wird dazu benutzt, ein Element auf der Seite auszuwählen. @@ -35,7 +35,7 @@ Man kann aber auch alle Elemente auf einer Seite auswählen! */ * { color:red; } /* farbe:rot */ /* -Angenommen wir haben folgendes Element auf einer Seite: +Angenommen, wir haben folgendes Element auf einer Seite:
    */ @@ -170,7 +170,7 @@ empfohlen ist --> ## Spezifität Ein Element kann natürlich auch von mehr als einer Regel in einem Stylesheet -angesprochen werdenm und kann eine Eigenschaft auch öfters als einmal zugewiesen +angesprochen werden und kann eine Eigenschaft auch öfters als einmal zugewiesen bekommen. In diesen Fällen gibt es Regeln, die die Spezifität von Selektoren regeln. Wir haben dieses CSS: -- cgit v1.2.3 From 2eb57cb02376df701e80d2692deab5809214171a Mon Sep 17 00:00:00 2001 From: Barton Stanley Date: Fri, 31 Jan 2020 13:04:15 -0600 Subject: Change "invokation" to "invocation" --- ruby.html.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ruby.html.markdown b/ruby.html.markdown index 3fc2ed2d..376f4a47 100644 --- a/ruby.html.markdown +++ b/ruby.html.markdown @@ -256,7 +256,7 @@ else 'else, also optional' end -# If a condition controls invokation of a single statement rather than a block of code +# If a condition controls invocation of a single statement rather than a block of code # you can use postfix-if notation warnings = ['Patronimic is missing', 'Address too short'] puts("Some warnings occurred:\n" + warnings.join("\n")) if !warnings.empty? -- cgit v1.2.3 From d5432679c75c57dd280af957df8063d10b30db99 Mon Sep 17 00:00:00 2001 From: Barton Stanley Date: Fri, 31 Jan 2020 14:20:14 -0600 Subject: [CONTRIBUTING.markdown] Change "buid" to "build" --- CONTRIBUTING.markdown | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/CONTRIBUTING.markdown b/CONTRIBUTING.markdown index 18a5a5d7..3dfd38ce 100644 --- a/CONTRIBUTING.markdown +++ b/CONTRIBUTING.markdown @@ -83,7 +83,7 @@ addition or not. ## Building the site locally -You can buid the site locally to test your changes. Follow the steps below. +You can build the site locally to test your changes. Follow the steps below. * Install Ruby language runtime and RubyGems. See [here](https://middlemanapp.com/basics/install/) for more details. * Clone or zip download the [learnxinyminutes-site](https://github.com/adambard/learnxinyminutes-site) repo. -- cgit v1.2.3 From 70e59f7f3d1229d30f11683e3b0a86bdfdf40cd9 Mon Sep 17 00:00:00 2001 From: khswong <42327203+khswong@users.noreply.github.com> Date: Fri, 31 Jan 2020 16:30:16 -0800 Subject: [toml/en] Fix Formatting and Syntax Highlighting Switching between json code block and toml code block caused it to render improperly. Fixed. --- toml.html.markdown | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/toml.html.markdown b/toml.html.markdown index 4c76ee91..2b234965 100755 --- a/toml.html.markdown +++ b/toml.html.markdown @@ -12,7 +12,7 @@ It is an alternative to YAML and JSON. It aims to be more human friendly than JS Be warned, TOML's spec is still changing a lot. Until it's marked as 1.0, you should assume that it is unstable and act accordingly. This document follows TOML v0.4.0. -``` +```toml # Comments in TOML look like this. ################ @@ -223,8 +223,8 @@ emptyTableAreAllowed = true name = "Nail" sku = 284758393 color = "gray" - -# JSON-land styled structure: +``` +The equivalent in JSON would be: ```json { "products": [ @@ -242,6 +242,8 @@ color = "gray" ] } ``` + +```toml # You can create nested arrays of tables as well. Each double-bracketed # sub-table will belong to the nearest table element above it. @@ -266,11 +268,11 @@ color = "gray" [[fruit.color]] name = "yellow" note = "I am an array item in banana fruit's table/map" -``` - -# In JSON land, this code will be: +``` +The equivalent in JSON would be: ```json + { "fruit": [ { -- cgit v1.2.3
    Erster Tabellenkopf
    Erster Tabellenkopf Zweiter Tabllenkopf
    Erste Zeile, erste Spalte Erste Zeile, erste Spalte Erste Zeile, zweite Spalte