Very simple gulp watch for coffeescript

gulpfile.js

/// requires
var gulp    = require('gulp'),
    plumber = require('gulp-plumber'),
    coffee  = require('gulp-coffee'),
    watch   = require('gulp-watch');


/// dirs
var assets_dir = 'assets/';
var coffee_dir = assets_dir + 'coffee/',
        js_dir = assets_dir + 'js/';


/// tasks
gulp.task('default', function ()
{
    gulp.src( coffee_dir + '*.coffee')
        .pipe( plumber({ errorHandler : errorHandler }) )
	.pipe( watch( coffee_dir + '*.coffee' ) )
	.pipe( coffee() )
	.pipe( gulp.dest( js_dir ) );
});


/// functions
errorHandler = function (error)
{
    console.error(error);
}