fairmont

Fairmont

A collection of useful CoffeeScript/JavaScript functions.

General Purpose Functions

w Split a string on whitespace. Useful for concisely creating arrays of strings.

console.log word for word in w "foo bar baz"

type Get the type of a value. Possible values are: number, string, 'boolean, data, regexp, function, array, object, null, undefined. Adapted from The CoffeeScript Cookbook and based on Douglas Crockford's remedial JavaScript blog post.

foo() if type( foo ) == "function"

timer Set a timer. Takes an interval in microseconds and an action. Returns a function to cancel the timer. Basically, a more convenient way to call setTimeout and clearTimeout.

cancel = timer 1000, -> console.log "Done"
cancel()

Array Functions

remove Destructively remove an element from an array. Returns the element removed.

a = w "foo bar baz"
remove( a, "bar" )

uniq Takes an array and returns a new array with all duplicate values from the original array removed. Also takes an optional hash function that defaults to calling toString on the elements.

uniq [1,2,3,1,2,3,4,5,6,3,6,2,4]
# returns [1,2,3,4,5,6]

File System Functions

All file-system functions are based on Node's fs API. This is not required unless the function is actually invoked.

exists Check to see if a file exists.

source = read( sourcePath ) if exists( sourcePath )

read Read a file synchronously and return a UTF-8 string of the contents.

source = read( sourcePath ) if exists( sourcePath )

write Synchronously write a UTF-8 string to a file.

write( file.replace( /foo/g, 'bar' ) )

readdir Synchronously get the contents of a directory as an array.

for file in readdir("documents")
  console.log read( file ) if stat( file ).isFile()

stat Synchronously get the stat object for a file.

for file in readdir("documents")
  console.log read( file ) if stat( file ).isFile()

chdir Change directories, execute a function, and then restore the original working directory.

chdir "documents", ->
  console.log read( "README" )

Hashing/Encoding Functions

md5 Return the MD5 hash of a string.

nutshell = md5( myLifeStory )

base64 Base64 encode a string. (Not URL safe.)

image = data: base64( imageData )

Object Functions

include Adds the properties of one or more objects to another.

include( @, ScrollbarMixin, SidebarMixin )

merge Creates new object by progressively adding the properties of each given object.

options = merge( defaults, globalOptions, localOptions )

delegate Delegates from one object to another by creating functions in the first object that call the second.

delegate( aProxy, aServer )

Object Mixins

Mixins are objects that you can include into another, typically adding features to an object in the process.

Property Add a property method to a class, making it easier to define getters and setters on its prototype.

class Foo
  include @, Property
  property "foo", get: -> @_foo, set: (v) -> @_foo = v

Properties defined using property are enumerable.

Function Functions

memoize A very simple way to cache results of functions that take a single argument. Also takes an optional hash function that defaults to calling toString on the function's argument.

nickname = (email) ->
  expensiveLookupToGetNickname( email )
  
memoize( nickname )