Directory tree traversal

traverse.coffee

fs = require('fs')
util = require('util')
path = require('path')

flatten = (a, b) ->
  if typeof b is 'undefined'
    b = a
    a = []
  b = b.reduce(flatten, []) if typeof b is 'object'
  a = [a] if typeof a isnt 'object'
  a.concat(b)

traverse = (index, list, callback) ->
  [index, list, callback] = [0, index, list] if arguments.length == 2
  fs.readdir list[index], (err, files) ->
    if files? # Directory
      files = files.map (f) -> path.join(list[index], f)
      list.splice index, 1, files
      list = flatten(list)
      traverse(0, list, callback)
    else # File
      nxt = index + 1 # Move forward? 
      if nxt < list.length then traverse(nxt, list, callback) else callback(list)

traverse [__dirname], (files) ->
  console.log(files)