This should be standard in CoffeeScript and Javascript

tostring.coffee

# Get a printable version of all properties in an object. Ignores function
# properties. DO NOT MAKE THIS A PROPERTY OF Object!
window.objectToString = (obj) ->
  t = typeof obj
  if (t is "number") or (t is "boolean")
    "#{obj}"
  else if window.isArray(obj)
    window._arrayToString(obj)
  else if t is "string"
    '"' + obj + '"'
  else if t is "function"
    null
  else if t is "object"
    "#{window._propertiesToString(obj)}"
  else
    toString.call(obj)

window._propertiesToString = (obj) ->
  a = []
  for own k, v of obj
    if v?
      s = window.objectToString(v)
      a.push '"' + k + '": ' + s if s?

  "{#{a.join(', ')}}"

window._arrayToString = (a) ->
  r = []
  for i in a
    if typeof i is 'string'
      r.push '"' + i + '"'
    else if 'function' is typeof i
      # skip
    else
      r.push i

  if r.length is 0 then '[]' else "[" + r.join(", ") + "]"

# Clone of underscore's isArray function, so we don't have to depend on
# underscore.js
window.isArray = Array.isArray || (obj) -> toString.call(obj) == '[object Array]'