Moved back to scripts instead of objects (FF4, performance).

Author: Dave Artz

A.getjs/A.getjs.js

@@ -1,61 +1,79 @@
-/*!
-* A.getJS v1.0
-* http://www.artzstudio.com/A.js/getJS/
-*
-* Developed by: 
-* - Dave Artz http://www.artzstudio.com/
-*
-* Copyright (c) 2010
-* Not yet licensed cuz I lack free time.
-*/
-
 /*
-* A.getJS is a script that loads JavaScript asynchronously while
-* preserving execution order via a chaining interface.
-* 
-* @author        Dave Artz
-* @copyright     (c) 2010 Dave Artz
-*/
+ * A.getJS v0.9
+ * http://www.artzstudio.com/A.js/getJS/
+ *
+ * Developed by: 
+ * - Dave Artz http://www.artzstudio.com/
+ *
+ * Copyright (c) 2010
+ * Not yet licensed cuz I lack free time.
+ */
+ 
+/*
+ * A.getJS is a script that loads JavaScript asynchronously while
+ * preserving execution order via a chaining interface.
+ * 
+ * @author        Dave Artz
+ * @copyright     (c) 2010 Dave Artz
+ */
 (function( document ) {
 
-// Artz: Consider implementing Image() for IE? Might be more bloaty.
-// http://platform.aol.com/code/upusi/2/edit
-function getObject ( elem, url, callback, type ) {
-	
-	var	object = document.createElement( elem ),
+function getScript ( url, callback, type ) {
+
+	var	script = document.createElement("script"),
 		done = 0;
 
-	object.src = object.data = url;
-	object.type = type;
-	object.width = object.height = 0;
+	script.src = url;
+	script.type = type || "";  // Assumes text/javascript.
+	
+	// This is for Firefox 4
+	// https://developer.mozilla.org/En/HTML/Element/Script
+	// We basically make it synchronously like in FF3.
+	// Not ideal, but we found <object> to be slower
+	// DOM nodes.
+	script.async = false;
 
 	// Attach handlers for all browsers
-	object[ strOnLoad ] = object[ strOnReadyStateChange ] = function() {
-		
-		if ( !done && (!object[ strReadyState ] ||
-			object[ strReadyState ] == "loaded" || object[ strReadyState ] == "complete") ) {
-			
+	script[ strOnLoad ] = script[ strOnReadyStateChange ] = function(){
+
+		if ( !done && (!script[ strReadyState ] ||
+				script[ strReadyState ] == "loaded" || script[ strReadyState ] == "complete") ) {
+
 			// Tell global scripts object this script has loaded.
 			// Set scriptDone to prevent this function from being called twice.
 			done = 1;
-			
+
 			callback( url );
 
 			// Handle memory leak in IE
-			object[ strOnLoad ] = object[ strOnReadyStateChange ] = null;
-			docElement.removeChild( object );
+			script[ strOnLoad ] = script[ strOnReadyStateChange ] = null;
+			docElement.removeChild( script );
 		}
 	};
 
-	docElement.appendChild( object );
+	docElement.appendChild( script );
 }
-
+	
 function getJS ( urlKey, urlKeyCallback ) {
+		
+	function geckoCallback ( url ) {
+		// If both scripts loaded, it's time to party.
+		++urlCount == urlCountTotal && urlKeyCallback && urlKeyCallback();
+	}
+		
+	function getJSCallback ( url ) {
+			
+		// Remember that we have this script cached.
+		urlCached[ url ] = 1;
+
+		// If this callback happens to be for the first urlKey
+		// in the chain, we can trigger the execution. 
+		urlKey == urlKeyChain[0] && executeJS();
+	}
 
 	function executeJS () {
 
 		function executeCallback () {
-			
 			// If all scripts have been cached in the set, it's time
 			// to execute the urlKey callback after the script loads.
 			if ( ++cacheCount == thisUrlsCount ) {
@@ -70,77 +88,67 @@ function getJS ( urlKey, urlKeyCallback ) {
 		}
 
 		for ( var i = 0,
-			thisUrlKey = urlKeyChain[0] || "",
-			thisUrls = thisUrlKey.split( urlSplit ),
-			thisUrl,
-			thisUrlsCount = thisUrls.length,
-			thisUrlKeyCallback = urlKeyCallbacks[ thisUrlKey ],
-			cacheCount = 0; i < thisUrlsCount; i++ ) {
+				thisUrlKey = urlKeyChain[0] || "",
+				thisUrls = thisUrlKey.split( urlSplit ),
+				thisUrl,
+				thisUrlsCount = thisUrls.length,
+				thisUrlKeyCallback = urlKeyCallbacks[ thisUrlKey ],
+				cacheCount = 0; i < thisUrlsCount; i++ ) {
 
 			thisUrl = thisUrls[i];
-			
+
 			if ( urlCached[ thisUrl ] ) {
 				if ( urlExecuted[ thisUrl ] ) {
 					// If we already executed, just do the callback.
 					executeCallback();					
 				} else {
 					// Rememeber that this script already executed.
 					urlExecuted[ thisUrl ] = 1;
-					type = ""; // Clear out the type so we load normally.
-					getObject( strScript, thisUrl, executeCallback, type );	
+					getScript( thisUrl, executeCallback );	
 				}
 			}
 		}
 	}
-	
-	function getJSCallback ( url ) {
 
-		// Remember that we have this script cached.
-		urlCached[ url ] = 1;
-		
-		// If this callback happens to be for the first urlKey
-		// in the chain, we can trigger the execution. 
-		urlKey == urlKeyChain[0] && executeJS();
-	}
-	
 	var urls = urlKey.split( urlSplit ),
+		urlCount = 0,
 		urlCountTotal = urls.length,
 		i = 0,
-		elem = strScript,
 		type,
 		urlKeyChain = this.c; // Contains an arays of urlKeys of this chain, if available.
 
-	// Gecko no longer does what we want out of the box.
-	// Use object instead.
+	// Gecko does what we want out of the box, sort of.
+	// Bypass our super special callback.
 	if ( isGecko ) {
 
-		elem = "object";
+		getJSCallback = geckoCallback;
 
 	// Manage callbacks and execution order manually.
 	} else {
-	
+		
 		// We set this to something bogus so browsers do not 
 		// execute code on our initial request.
 		// http://ejohn.org/blog/javascript-micro-templating/
 		type = "c";
+		
+		// If this is a new chain, start a new array, otherwise push the new guy in.
+		// This is used to preserve execution order for non FF browsers.
+		if ( urlKeyChain ) {
+			// Push the urlKey into the chain.
+			urlKeyChain.push( urlKey );
+		} else {
+			// Create a new urlKeyChain to pass on to others.
+			urlKeyChain = [ urlKey ];
+		}
+
+		// Remember the original callback for this key for later.
+		urlKeyCallbacks[ urlKey ] = urlKeyCallback;
 	}
-	
-	// If this is a new chain, start a new array, otherwise push the new guy in.
-	// This is used to preserve execution order for non FF browsers.
-	if ( urlKeyChain ) {
-		// Push the urlKey into the chain.
-		urlKeyChain.push( urlKey );
-	} else {
-		// Create a new urlKeyChain to pass on to others.
-		urlKeyChain = [ urlKey ];
-	}
-	
-	// Remember the original callback for this key for later.
-	urlKeyCallbacks[ urlKey ] = urlKeyCallback;
+				
 	// Cache the scripts requested.
 	for (; i < urlCountTotal; i++) {
 		// Fetch the script.
-		getObject( elem, urls[i], getJSCallback, type );
+		getScript( urls[i], getJSCallback, type );
 	}
 
 	return {
@@ -150,14 +158,13 @@ function getJS ( urlKey, urlKeyCallback ) {
 }
 
 var	docElement = document.documentElement,
-	//	Artz: Just making things smaller, uncomment if people care.
-	//	head = document.getElementsByTagName("head")[0] || docElement,  
+//	Artz: Just making things smaller, uncomment if people care.
+//	head = document.getElementsByTagName("head")[0] || docElement,  
 	urlKeyCallbacks = {},
 	urlCached = {},
 	urlExecuted = {},
 	urlSplit = ",",	
 
-	strScript = "script",
 	strReadyState = "readyState",
 	strOnReadyStateChange = "onreadystatechange",
 	strOnLoad = "onload",

A.getjs/A.getjs.min.js

@@ -35,7 +35,7 @@
 
 })(window, document);
 
-
+A.log("Starting...");
 A.getJS("javascript.php?num=1&sleep=2,javascript.php?num=2", function(){
 	A.log("<b>Executing callback: javascript.php?num=1,javascript.php?num=2</b>");
 }).getJS("javascript.php?num=4", function(){