Format Money in Coffeescript

format_money.coffee

# Inspired by http://stackoverflow.com/a/149099/1649199

Number::formatMoney = (t=',', d='.', c='$') ->
  n = this
  s = if n < 0 then "-#{c}" else c
  i = Math.abs(n).toFixed(2)
  j = (if (j = i.length) > 3 then j % 3 else 0)
  s += i.substr(0, j) + t if j
  return s + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + t)