Delete pogoscript (#5199)

pogo.html.markdown

@@ -1,202 +0,0 @@
----
-language: PogoScript
-contributors:
-    - ["Tim Macfarlane", "http://github.com/refractalize"]
-filename: learnPogo.pogo
----
-
-Pogoscript is a little language that emphasises readability, DSLs and provides excellent asynchronous primitives for writing connected JavaScript applications for the browser or server.
-
-``` javascript
-// defining a variable
-water temperature = 24
-
-// re-assigning a variable after its definition
-water temperature := 26
-
-// functions allow their parameters to be placed anywhere
-temperature at (a) altitude = 32 - a / 100
-
-// longer functions are just indented
-temperature at (a) altitude :=
-    if (a < 0)
-        water temperature
-    else
-        32 - a / 100
-
-// calling a function
-current temperature = temperature at 3200 altitude
-
-// this function constructs a new object with methods
-position (x, y) = {
-    x = x
-    y = y
-
-    distance from position (p) =
-        dx = self.x - p.x
-        dy = self.y - p.y
-        Math.sqrt (dx * dx + dy * dy)
-}
-
-// `self` is similar to `this` in JavaScript with the
-// exception that `self` isn't redefined in each new
-// function definition
-// `self` just does what you expect
-
-// calling methods
-position (7, 2).distance from position (position (5, 1))
-
-// as in JavaScript, objects are hashes too
-position.'x' == position.x == position.('x')
-
-// arrays
-positions = [
-    position (1, 1)
-    position (1, 2)
-    position (1, 3)
-]
-
-// indexing an array
-positions.0.y
-
-n = 2
-positions.(n).y
-
-// strings
-poem = 'Tail turned to red sunset on a juniper crown a lone magpie cawks.
-        Mad at Oryoki in the shrine-room -- Thistles blossomed late afternoon.
-        Put on my shirt and took it off in the sun walking the path to lunch.
-        A dandelion seed floats above the marsh grass with the mosquitos.
-        At 4 A.M. the two middleaged men sleeping together holding hands.
-        In the half-light of dawn a few birds warble under the Pleiades.
-        Sky reddens behind fir trees, larks twitter, sparrows cheep cheep cheep
-        cheep cheep.'
-
-// that's Allen Ginsburg
-
-// interpolation
-outlook = 'amazing!'
-console.log "the weather tomorrow is going to be #(outlook)"
-
-// regular expressions
-r/(\d+)m/i
-r/(\d+) degrees/mg
-
-// operators
-true @and true
-false @or true
-@not false
-2 < 4
-2 >= 2
-2 > 1
-
-// plus all the javascript ones
-
-// to define your own
-(p1) plus (p2) =
-    position (p1.x + p2.x, p1.y + p2.y)
-
-// `plus` can be called as an operator
-position (1, 1) @plus position (0, 2)
-// or as a function
-(position (1, 1)) plus (position (0, 2))
-
-// explicit return
-(x) times (y) = return (x * y)
-
-// new
-now = @new Date ()
-
-// functions can take named optional arguments
-spark (position, color: 'black', velocity: {x = 0, y = 0}) = {
-    color = color
-    position = position
-    velocity = velocity
-}
-
-red = spark (position 1 1, color: 'red')
-fast black = spark (position 1 1, velocity: {x = 10, y = 0})
-
-// functions can unsplat arguments too
-log (messages, ...) =
-    console.log (messages, ...)
-
-// blocks are functions passed to other functions.
-// This block takes two parameters, `spark` and `c`,
-// the body of the block is the indented code after the
-// function call
-
-render each @(spark) into canvas context @(c)
-    ctx.begin path ()
-    ctx.stroke style = spark.color
-    ctx.arc (
-        spark.position.x + canvas.width / 2
-        spark.position.y
-        3
-        0
-        Math.PI * 2
-    )
-    ctx.stroke ()
-
-// asynchronous calls
-
-// JavaScript both in the browser and on the server (with Node.js)
-// makes heavy use of asynchronous IO with callbacks. Async IO is
-// amazing for performance and making concurrency simple but it
-// quickly gets complicated.
-// Pogoscript has a few things to make async IO much much easier
-
-// Node.js includes the `fs` module for accessing the file system.
-// Let's list the contents of a directory
-
-fs = require 'fs'
-directory listing = fs.readdir! '.'
-
-// `fs.readdir()` is an asynchronous function, so we can call it
-// using the `!` operator. The `!` operator allows you to call
-// async functions with the same syntax and largely the same
-// semantics as normal synchronous functions. Pogoscript rewrites
-// it so that all subsequent code is placed in the callback function
-// to `fs.readdir()`.
-
-// to catch asynchronous errors while calling asynchronous functions
-
-try
-    another directory listing = fs.readdir! 'a-missing-dir'
-catch (ex)
-    console.log (ex)
-
-// in fact, if you don't use `try catch`, it will raise the error up the
-// stack to the outer-most `try catch` or to the event loop, as you'd expect
-// with non-async exceptions
-
-// all the other control structures work with asynchronous calls too
-// here's `if else`
-config =
-    if (fs.stat! 'config.json'.is file ())
-        JSON.parse (fs.read file! 'config.json' 'utf-8')
-    else
-        {
-            color: 'red'
-        }
-
-// to run two asynchronous calls concurrently, use the `?` operator.
-// The `?` operator returns a *future* which can be executed to
-// wait for and obtain the result, again using the `!` operator
-
-// we don't wait for either of these calls to finish
-a = fs.stat? 'a.txt'
-b = fs.stat? 'b.txt'
-
-// now we wait for the calls to finish and print the results
-console.log "size of a.txt is #(a!.size)"
-console.log "size of b.txt is #(b!.size)"
-
-// futures in Pogoscript are analogous to Promises
-```
-
-That's it.
-
-Download [Node.js](http://nodejs.org/) and `npm install pogo`.
-
-There is plenty of documentation on [http://pogoscript.org/](http://pogoscript.org/), including a [cheat sheet](http://pogoscript.org/cheatsheet.html), a [guide](http://pogoscript.org/guide/), and how [Pogoscript translates to Javascript](http://featurist.github.io/pogo-examples/). Get in touch on the [google group](http://groups.google.com/group/pogoscript) if you have questions!