[JavaScript] 関数遅延実行

Snippets.js

/**
 * 関数遅延実行
 */
deferred=(function(){
	var _w=window,_d=window.document;
	var deferred_default=function(func){_w.setTimeout(function(){func()},0);};
	var deferred_faster_way_readystatechange=((location.protocol==="http:")&&!_w.opera&&/\bMSIE\b/.test(navigator.userAgent))&&function(func){
		var script = _d.createElement("script");
		script.type = "text/javascript";
		script.src  = "javascript:";
		script.onreadystatechange=function(){func()};
	};
	var deferred_faster_way_Image=((typeof(Image)!=="undefined")&&_d.addEventListener)&&function(func){
		var img = new Image();
		var handler=function(){func();};
		img.addEventListener("load", handler, false);
		img.addEventListener("error", handler, false);
		img.src = "data:,/ _ / X";
	};
	return deferred_faster_way_readystatechange||deferred_faster_way_Image||deferred_default;
})();