gulp-build-module.js

var 	gulp = require('gulp'),
	concat = require('gulp-concat'),
	wrap = require('gulp-wrap'),
	multipipe = require('multipipe'),
	
	spaceRe = /\s+/g,
	wrapper = '(function(undefined){\n\n<%= contents %>\n}());';

module.exports = function buildModule(src, dest, watch) {
	var name = String(src).replace(spaceRe, '-');

	function task() {	
		var pipe = multipipe(
			gulp.src(src),
			concat(),
			wrap(wrapper),
			gulp.dest(dest)
		);
		
		pipe.on('error', function(err) {
			console.warn(err);
		});
	}
	
	gulp.task(name, task);
	gulp.watch(watch, name);
		
};