_calls.coffee

module.exports = (args) ->
  _get_callback = (args, pos) ->
    if args.length > pos - 1
      candidate = args[args.length-pos]
      if candidate && typeof candidate == 'function'
        candidate

  win = ->
  fail = ->
  if candidate = _get_callback args, 1
    win = candidate

    if candidate = _get_callback args, 2
      fail = win
      win = candidate

  [ win, fail ]

bar.coffee

_calls = require './_calls'

class Bar

  foo: (arg='nothing') ->
    [ _win, _fail ] = _calls arguments

    console.log "Was passed #{arg}"

    @bar _win, _fail

  bar: ->
    [ _win, _fail ] = _calls arguments

    console.log "Calling _win"
    _win( "Winning" )

    console.log "Calling _fail"
    _fail( "Failing" )


b = new Bar

console.log "\n# can call with no args"
b.bar()

console.log "\n# can call with a single callback - will be assigned to _win, so the success callback"
b.bar (msg) ->
  console.log "Called back with #{msg}"

console.log "\n# can call with two callbacks, first is win, second is fail"
b.bar (msg) ->
    console.log "Called back with #{msg}"
  , (msg) ->
    console.log "Failed out with #{msg}"


console.log "\n# can call with just an arg"
b.foo 'foobar'

console.log "\n# can call with an arg and a single callback"
b.foo 'foobar', (msg) ->
  console.log "Called back with #{msg}"

console.log "\n# can also combine both with any args"
b.foo 'foobar'
  , (msg) ->
    console.log "Called back with #{msg}"
  , (msg) ->
    console.log "Failed out with #{msg}"