Part of my main Cakefile that pre-compiles Handlebars templates. This script watches the specified directory for changes and writes to templates.js

handlebars-precompiler-cakefile.coffee

fs = require 'fs'
{print} = require 'sys'
{log, error} = console; print = log
{spawn, exec} = require 'child_process'

run = (name, args...) ->
  proc = spawn(name, args)
  proc.stdout.on('data', (buffer) -> print buffer if buffer = buffer.toString().trim())
  proc.stderr.on('data', (buffer) -> error buffer if buffer = buffer.toString().trim())
  proc.on 'exit', (status) ->
    process.exit(1) if status isnt 0
    
task 'watch', 'Watch template dir for changes and compile ', () ->
  # pre-compile client-side templates
  templatesDir = 'public/js/templates/src'

  compileHandlebars = (template) ->  
    run 'handlebars', templatesDir, '-f', 'public/js/templates/templates.js'
    run 'uglifyjs', 'public/js/templates/templates.js', '-o','public/js/templates/templates.js'

  # watch client side templates
  templates = fs.readdirSync templatesDir
  for i in [0...templates.length]
    template = templatesDir + '/' + templates[i]
    do (template) ->
      fs.watchFile template, (curr, prev) ->
        if +curr.mtime isnt +prev.mtime
          compileHandlebars(template)

  compileHandlebars()