Restart Coffee server on file change

Cakefile

fs    = require 'fs'
log   = console.log
spawn = require('child_process').spawn

task 'server', 'Start server.coffee and restart on file change', ->
  log "Starting server, kill with Ctrl-c"
  server = spawn "coffee", ["server.coffee"]
  server.stdout.on "data", (data) ->
    log "#{data}"

  server.on "exit", ->
    log "Restart server"
    invoke "server"

  fs.watchFile "server.coffee", (curr, prev) ->
    if curr.mtime > prev.mtime
      server.kill()