Debounce function execution in CoffeeScript

Debounce.coffee

# Based on:
# http://unscriptable.com/2009/03/20/debouncing-javascript-methods/

debounce = (func, threshold, execAsap) ->
  timeout = null
  (args...) ->
    obj = this
    delayed = ->
      func.apply(obj, args) unless execAsap
      timeout = null
    if timeout
      clearTimeout(timeout)
    else if (execAsap)
      func.apply(obj, args)
    timeout = setTimeout delayed, threshold || 100



# USAGE
window.addEventListener 'resize', displayViewPortSize

displayViewPortSize = debounce((e) ->
  # do something after window resizing stops  
, 250, false)


displayViewPortSize = debounce((e) ->
  # do something once and then after every 250ms
, 250, true)