diff options
| -rw-r--r-- | bash.html.markdown | 13 | ||||
| -rw-r--r-- | c.html.markdown | 9 | ||||
| -rw-r--r-- | cs-cz/python3.html.markdown | 6 | ||||
| -rw-r--r-- | d.html.markdown | 50 | ||||
| -rw-r--r-- | pt-br/c-pt.html.markdown | 19 | ||||
| -rw-r--r-- | python3.html.markdown | 4 | ||||
| -rw-r--r-- | xml.html.markdown | 4 |
7 files changed, 67 insertions, 38 deletions
diff --git a/bash.html.markdown b/bash.html.markdown index 191f916a..211d2944 100644 --- a/bash.html.markdown +++ b/bash.html.markdown @@ -90,17 +90,26 @@ else echo "Your name is your username" fi +# NOTE: if $Name is empty, bash sees the above condition as: +if [ -ne $USER ] +# which is invalid syntax +# so the "safe" way to use potentially empty variables in bash is: +if [ "$Name" -ne $USER ] ... +# which, when $Name is empty, is seen by bash as: +if [ "" -ne $USER ] ... +# which works as expected + # There is also conditional execution echo "Always executed" || echo "Only executed if first command fails" echo "Always executed" && echo "Only executed if first command does NOT fail" # To use && and || with if statements, you need multiple pairs of square brackets: -if [ $Name == "Steve" ] && [ $Age -eq 15 ] +if [ "$Name" == "Steve" ] && [ "$Age" -eq 15 ] then echo "This will run if $Name is Steve AND $Age is 15." fi -if [ $Name == "Daniya" ] || [ $Name == "Zach" ] +if [ "$Name" == "Daniya" ] || [ "$Name" == "Zach" ] then echo "This will run if $Name is Daniya OR Zach." fi diff --git a/c.html.markdown b/c.html.markdown index 3339032f..bfdf276c 100644 --- a/c.html.markdown +++ b/c.html.markdown @@ -54,6 +54,8 @@ int function_2(void); // Must declare a 'function prototype' before main() when functions occur after // your main() function. int add_two_ints(int x1, int x2); // function prototype +// although `int add_two_ints(int, int);` is also valid (no need to name the args), +// it is recommended to name arguments in the prototype as well for easier inspection // Your program's entry point is a function called // main with an integer return type. @@ -74,6 +76,9 @@ int main (int argc, char** argv) /////////////////////////////////////// // Types /////////////////////////////////////// + + // All variables MUST be declared at the top of the current block scope + // we declare them dynamically along the code for the sake of the tutorial // ints are usually 4 bytes int x_int = 0; @@ -232,7 +237,7 @@ int main (int argc, char** argv) 0 || 1; // => 1 (Logical or) 0 || 0; // => 0 - // Conditional expression ( ? : ) + // Conditional ternary expression ( ? : ) int e = 5; int f = 10; int z; @@ -302,6 +307,8 @@ int main (int argc, char** argv) for (i = 0; i <= 5; i++) { ; // use semicolon to act as the body (null statement) } + // Or + for (i = 0; i <= 5; i++); // branching with multiple choices: switch() switch (a) { diff --git a/cs-cz/python3.html.markdown b/cs-cz/python3.html.markdown index 11c8a654..6d2fd1eb 100644 --- a/cs-cz/python3.html.markdown +++ b/cs-cz/python3.html.markdown @@ -48,7 +48,7 @@ Poznámka: Tento článek je zaměřen na Python 3. Zde se můžete [naučit sta -5 // 3 # => -2 -5.0 // 3.0 # => -2.0 -# Pokud použiteje desetinné číslo, výsledek je jím také +# Pokud použijete desetinné číslo, výsledek je jím také 3 * 2.0 # => 6.0 # Modulo @@ -420,7 +420,7 @@ next(iterator) # Vyhodí StopIteration ## 4. Funkce #################################################### -# Pro vytvoření nové funkce použijte def +# Pro vytvoření nové funkce použijte klíčové slovo def def secist(x, y): print("x je {} a y je {}".format(x, y)) return x + y # Hodnoty se vrací pomocí return @@ -520,7 +520,7 @@ class Clovek(object): # podtržítka na začátku a na konci značí, že se jedná o atribut nebo # objekt využívaný Pythonem ke speciálním účelům, ale můžete sami # definovat jeho chování. Metody jako __init__, __str__, __repr__ - # a další se nazývají "magické metody". Nikdy nepoužívejte toto + # a další se nazývají "magické metody". Nikdy nepoužívejte toto # speciální pojmenování pro běžné metody. def __init__(self, jmeno): # Přiřazení parametru do atributu instance jmeno diff --git a/d.html.markdown b/d.html.markdown index 88a83e41..80c1dc65 100644 --- a/d.html.markdown +++ b/d.html.markdown @@ -74,16 +74,18 @@ are passed to functions by value (i.e. copied) and classes are passed by referen we can use templates to parameterize all of these on both types and values! ```c -// Here, T is a type parameter. Think <T> from C++/C#/Java +// Here, 'T' is a type parameter. Think '<T>' from C++/C#/Java. struct LinkedList(T) { T data = null; - LinkedList!(T)* next; // The ! is used to instaniate a parameterized type. Again, think <T> + + // Use '!' to instantiate a parameterized type. Again, think '<T>'. + LinkedList!(T)* next; } class BinTree(T) { T data = null; - // If there is only one template parameter, we can omit the parentheses + // If there is only one template parameter, we can omit the parentheses. BinTree!T left; BinTree!T right; } @@ -98,13 +100,11 @@ enum Day { Saturday, } -// Use alias to create abbreviations for types - +// Use alias to create abbreviations for types. alias IntList = LinkedList!int; alias NumTree = BinTree!double; // We can create function templates as well! - T max(T)(T a, T b) { if(a < b) return b; @@ -112,9 +112,8 @@ T max(T)(T a, T b) { return a; } -// Use the ref keyword to ensure pass by referece. -// That is, even if a and b are value types, they -// will always be passed by reference to swap +// Use the ref keyword to ensure pass by reference. That is, even if 'a' and 'b' +// are value types, they will always be passed by reference to 'swap()'. void swap(T)(ref T a, ref T b) { auto temp = a; @@ -122,13 +121,13 @@ void swap(T)(ref T a, ref T b) { b = temp; } -// With templates, we can also parameterize on values, not just types +// With templates, we can also parameterize on values, not just types. class Matrix(uint m, uint n, T = int) { T[m] rows; T[n] columns; } -auto mat = new Matrix!(3, 3); // We've defaulted type T to int +auto mat = new Matrix!(3, 3); // We've defaulted type 'T' to 'int'. ``` @@ -138,21 +137,20 @@ have the syntax of POD structures (`structure.x = 7`) with the semantics of getter and setter methods (`object.setX(7)`)! ```c -// Consider a class parameterized on a types T, U - +// Consider a class parameterized on types 'T' & 'U'. class MyClass(T, U) { T _data; U _other; - } -// And "getter" and "setter" methods like so +// And "getter" and "setter" methods like so: class MyClass(T, U) { T _data; U _other; - // Constructors are always named `this` + // Constructors are always named 'this'. this(T t, U u) { + // This will call the setter methods below. data = t; other = u; } @@ -175,16 +173,24 @@ class MyClass(T, U) { _other = u; } } -// And we use them in this manner +// And we use them in this manner: void main() { - auto mc = MyClass!(int, string); + auto mc = new MyClass!(int, string)(7, "seven"); + + // Import the 'stdio' module from the standard library for writing to + // console (imports can be local to a scope). + import std.stdio; + + // Call the getters to fetch the values. + writefln("Earlier: data = %d, str = %s", mc.data, mc.other); - mc.data = 7; - mc.other = "seven"; + // Call the setters to assign new values. + mc.data = 8; + mc.other = "eight"; - writeln(mc.data); - writeln(mc.other); + // Call the getters again to fetch the new values. + writefln("Later: data = %d, str = %s", mc.data, mc.other); } ``` diff --git a/pt-br/c-pt.html.markdown b/pt-br/c-pt.html.markdown index 451df4f3..43688724 100644 --- a/pt-br/c-pt.html.markdown +++ b/pt-br/c-pt.html.markdown @@ -6,6 +6,7 @@ contributors: - ["Árpád Goretity", "http://twitter.com/H2CO3_iOS"] translators: - ["João Farias", "https://github.com/JoaoGFarias"] + - ["Elton Viana", "https://github.com/eltonvs"] lang: pt-br filename: c-pt.el --- @@ -139,13 +140,13 @@ int main() { int var_length_array[size]; // declara o VLA printf("sizeof array = %zu\n", sizeof var_length_array); - //Uma possível saída para esse programa seria: - // > Entre o tamanho do array:: 10 + // Uma possível saída para esse programa seria: + // > Entre o tamanho do array: 10 // > sizeof array = 40 // String são apenas arrays de caracteres terminados por um - // byte NUL (0x00), representado em string pelo caracter especial '\0'. - // (Não precisamos incluir o byte NUL em literais de string; o compilador + // byte nulo (0x00), representado em string pelo caracter especial '\0'. + // (Não precisamos incluir o byte nulo em literais de string; o compilador // o insere ao final do array para nós.) char uma_string[20] = "Isto é uma string"; // Observe que 'é' não está na tabela ASCII @@ -153,8 +154,8 @@ int main() { // Porém, comentários podem conter acentos printf("%s\n", uma_string); // %s formata a string - printf("%d\n", uma_string[16]); // => 0 - // i.e., byte #17 é 0 (assim como 18, 19, e 20) + printf("%d\n", uma_string[17]); // => 0 + // i.e., byte #18 é 0 (assim como o 19°, 20°, 21°...) // Se temos caracteres entre aspas simples, temos um caracter literal. // Seu tipo é `int`, *não* `char` (por razões históricas). @@ -220,11 +221,11 @@ int main() { 0 || 1; // => 1 (Ou lógico) 0 || 0; // => 0 - //Expressão condicional ( ? : ) + //Expressão condicional ternária ( ? : ) int a = 5; int b = 10; int z; - z = (a > b) ? a : b; // => 10 "se a > b retorne a, senão retorne b." + z = (a > b) ? a : b; // => 10 "se a > b retorne a, senão retorne b." //Operadores de incremento e decremento: char *s = "iLoveC"; @@ -290,6 +291,8 @@ int main() { for (i = 0; i <= 5; i++) { ; // Use ponto e vírgula para agir como um corpo (declaração nula) } + // Ou + for (i = 0; i <= 5; i++); // Criando branchs com escolhas múltiplas: switch() switch (alguma_expressao_integral) { diff --git a/python3.html.markdown b/python3.html.markdown index f3f4dd37..a1125c73 100644 --- a/python3.html.markdown +++ b/python3.html.markdown @@ -160,6 +160,10 @@ print("I'm Python. Nice to meet you!") # => I'm Python. Nice to meet you! # Use the optional argument end to change the end character. print("Hello, World", end="!") # => Hello, World! +# Simple way to get input data from console +input_string_var = input("Enter some data: ") # Returns the data as a string +# Note: In earlier versions of Python, input() method was named as raw_input() + # No need to declare variables before assigning to them. # Convention is to use lower_case_with_underscores some_var = 5 diff --git a/xml.html.markdown b/xml.html.markdown index 4d33e614..547deb08 100644 --- a/xml.html.markdown +++ b/xml.html.markdown @@ -83,7 +83,7 @@ With this tool, you can check the XML data outside the application logic. <!DOCTYPE note SYSTEM "Bookstore.dtd"> <bookstore> <book category="COOKING"> - <title >Everyday Italian</title> + <title>Everyday Italian</title> <price>30.00</price> </book> </bookstore> @@ -121,7 +121,7 @@ With this tool, you can check the XML data outside the application logic. <bookstore> <book category="COOKING"> - <title >Everyday Italian</title> + <title>Everyday Italian</title> <price>30.00</price> </book> </bookstore> |