A little Javascript function that loads a javascript file only if a javascript object exists. Can be used to load JS files that depend on other JS files sequentially

conditional script loader

function sequentialJSLoader(URL,conditionalObjName){

    if( typeof conditionalObjName != "undefined" 
	&& eval('typeof ' + conditionalObjName) === "undefined"
      ){
//	console.log(conditionalObjName + " not yet defined");
	window.setTimeout(function(){sequentialJSLoader(URL,conditionalObjName);},500);
	return;
    }
    var J = document.createElement("SCRIPT");
    J.type = "text/javascript";
    J.src = URL;
    document.getElementsByTagName("HEAD")[0].appendChild(J);
}