$.Deferred Pipeline

jquery.deferredPipeline.js

define(["jquery"], function($) {
	//
	// Given a list of functions that return a promise or an object,
	// Set them up to execute them in order using those promises.
	// and returns a promise that resolves after the last promises returned by the function pipeline resolves.
	//
	var deferredPipeline = $.deferredPipeline = function(/* [function, ]*/) {
		//reversed pipeline
		var toPipe = Array.prototype.slice.call(arguments).reverse();
		if (toPipe.length == 0) {
			return $.when();
		} else if (toPipe.length == 1) {
			return toPipe[i]();
		}
		var dfd = $.Deferred();
		var lastFunc = function() {
			toPipe[0](arguments).then(
				function(){dfd.resolve(arguments);},
				function(){dfd.reject(arguments);});
		};
		for (var i = 1;i<toPipe.length;i++) {
			var toResolveNext = lastFunc;
			lastFunc = function() {
				$.when(toPipe[i](arguments)).then(toResolveNext);
			};
		}
		return dfd.promise();
	};
	return deferredPipeline;
});