diff options
| -rw-r--r-- | bash.html.markdown | 26 | ||||
| -rw-r--r-- | javascript.html.markdown | 2 | ||||
| -rw-r--r-- | matlab.html.markdown | 6 | ||||
| -rw-r--r-- | self.html.markdown | 161 |
4 files changed, 192 insertions, 3 deletions
diff --git a/bash.html.markdown b/bash.html.markdown index 11c1f3a2..81d586c4 100644 --- a/bash.html.markdown +++ b/bash.html.markdown @@ -208,4 +208,30 @@ grep "^foo.*bar$" file.txt grep -c "^foo.*bar$" file.txt # if you literally want to search for the string, and not the regex, use fgrep (or grep -F) fgrep "^foo.*bar$" file.txt + + +# Read Bash shell builtins documentation with the bash 'help' builtin: +help +help help +help for +help return +help source +help . + +# Read Bash manpage documentation with man +apropos bash +man 1 bash +man bash + +# Read info documentation with info (? for help) +apropos info | grep '^info.*(' +man info +info info +info 5 info + +# Read bash info documentation: +info bash +info bash 'Bash Features' +info bash 6 +info --apropos bash ``` diff --git a/javascript.html.markdown b/javascript.html.markdown index 792cab98..a92dcb4a 100644 --- a/javascript.html.markdown +++ b/javascript.html.markdown @@ -46,7 +46,7 @@ doStuff() // Some basic arithmetic works as you'd expect. 1 + 1; // = 2 -.1 + .2; // = 0.30000000000000004 +0.1 + 0.2; // = 0.30000000000000004 8 - 1; // = 7 10 * 2; // = 20 35 / 5; // = 7 diff --git a/matlab.html.markdown b/matlab.html.markdown index 121f16de..2b9077d5 100644 --- a/matlab.html.markdown +++ b/matlab.html.markdown @@ -15,10 +15,12 @@ If you have any feedback please feel free to reach me at ```matlab % Comments start with a percent sign. -%{ Multi line comments look +%{ +Multi line comments look something like -this %} +this +%} % commands can span multiple lines, using '...': a = 1 + 2 + ... diff --git a/self.html.markdown b/self.html.markdown new file mode 100644 index 00000000..69524a84 --- /dev/null +++ b/self.html.markdown @@ -0,0 +1,161 @@ +--- +language: self +contributors: + - ["Russell Allen", "http://github.com/russellallen"] +filename: learnself.self +--- + +Self is a fast prototype based OO language which runs in its own JIT vm. Most development is done through interacting with live objects through a visual development environment called *morphic* with integrated browsers and debugger. + +Everything in Self is an object. All computation is done by sending messages to objects. Objects in Self can be understood as sets of key-value slots. + +# Constructing objects + +The inbuild Self parser can construct objects, including method objects. + +``` +"This is a comment" + +"A string:" +'This is a string with \'escaped\' characters.\n' + +"A 30 bit integer" +23 + +"A 30 bit float" +3.2 + +"-20" +-14r16 + +"An object which only understands one message, 'x' which returns 20" +(| + x = 20. +|) + +"An object which also understands 'x:' which sets the x slot" +(| + x <- 20. +|) + +"An object which understands the method 'doubleX' which +doubles the value of x and then returns the object" +(| + x <- 20. + doubleX = (x: x * 2. self) +|) + +"An object which understands all the messages +that 'traits point' understands". The parser +looks up 'traits point' by sending the messages +'traits' then 'point' to a known object called +the 'lobby'. It looks up the 'true' object by +also sending the message 'true' to the lobby." +(| parent* = traits point. + x = 7. + y <- 5. + isNice = true. +|) +``` + +# Sending messages to objects + +Messages can either be unary, binary or keyword. Precedence is in that order. Unlike Smalltalk, the precedence of binary messages must be specified, and all keywords after the first must start with a capital letter. Messages are separeated from their destination by whitespace. + +``` +"unary message, sends 'printLine' to the object '23' +which prints the string '23' to stdout and returns the receiving object (ie 23)" +23 printLine + +"sends the message '+' with '7' to '23', then the message '*' with '8' to the result" +(23 + 7) * 8 + +"sends 'power:' to '2' with '8' returns 256" +2 power: 8 + +"sends 'keyOf:IfAbsent:' to 'hello' with arguments 'e' and '-1'. +Returns 1, the index of 'e' in 'hello'." +'hello' keyOf: 'e' IfAbsent: -1 +``` + +# Blocks + +Self defines flow control like Smalltalk and Ruby by way of blocks. Blocks are delayed computations of the form: + +``` +[|:x. localVar| x doSomething with: localVar] +``` + +Examples of the use of a block: + +``` +"returns 'HELLO'" +'hello' copyMutable mapBy: [|:c| c capitalize] + +"returns 'Nah'" +'hello' size > 5 ifTrue: ['Yay'] False: ['Nah'] + +"returns 'HaLLO'" +'hello' copyMutable mapBy: [|:c| + c = 'e' ifTrue: [c capitalize] + False: ['a']] +``` + +Multiple expressions are separated by a period. ^ returns immediately. + +``` +"returns An 'E'! How icky!" +'hello' copyMutable mapBy: [|:c. tmp <- ''| + tmp: c capitalize. + tmp = 'E' ifTrue: [^ 'An \'E\'! How icky!']. + c capitalize + ] +``` + +Blocks are performed by sending them the message 'value' and inherit (delegate to) their contexts: +``` +"returns 0" +[|x| + x: 15. + "Repeatedly sends 'value' to the first block while the result of sending 'value' to the + second block is the 'true' object" + [x > 0] whileTrue: [x: x - 1]. + x +] value +``` + +# Methods + +Methods are like blocks but they are not within a context but instead are stored as values of slots. Unlike Smalltalk, methods by default return their final value not 'self'. + +``` +"Here is an object with one assignable slot 'x' and a method 'reduceXTo: y'. +Sending the message 'reduceXTo: 10' to this object will put +the object '10' in the 'x' slot and return the original object" +(| + x <- 50. + reduceXTo: y = ( + [x > y] whileTrue: [x: x - 1]. + self) +|) +. +``` + +# Prototypes + +Self has no classes. The way to get an object is to find a prototype and copy it. + +``` +| d | +d: dictionary copy. +d at: 'hello' Put: 23 + 8. +d at: 'goodbye' Put: 'No!. +"Prints No!" +( d at: 'goodbye' IfAbsent: 'Yes! ) printLine. +"Prints 31" +( d at: 'hello' IfAbsent: -1 ) printLine. +``` + +# Further information + +The [Self handbook](http://handbook.selflanguage.org) has much more information, and nothing beats hand-on experience with Self by downloading it from the [homepage](http://www.selflanguage.org). |