Stacking Script Event Loaders

I’ve been playing around with JavaScript once when I’ve encountered a problem about my scripts not working, especially those attached to event handlers. You could probably see JavaScript declarations like this on a script or another:

window.onload = functionName;

And, soon, I found out that a lot of plugins I have use the same declaration for initializing their scripts. So, I looked for references and realized that they overwrite one another by declaring that assignment operation over and over again. Looking for solutions, I came across two possible ways to do it:

1. if (typeof window.onload != 'function') {
   	window.onload = newOnLoadFn;
   } else {
   	var onLoadStack = window.onload;
   	window.onload = function() {
   		onLoadStack();
   		newOnLoadFn();
   	}
   }

2. var onLoadStack = window.onload;
   window.onload = function() {
   	if (typeof onLoadStack == 'function' && onLoadStack) {
   		onLoadStack();
   	}
   	newOnLoadFn();
   }

Coding preferences applies, as either basically does the same effect of stacking window.onload events. You could put them on a function if you must:

function addOnLoadEvent(newOnLoadFn) {
	if (typeof window.onload != 'function') {
		window.onload = newOnLoadFn;
	} else {
		var onLoadStack = window.onload;
		window.onload = function() {
			onLoadStack();
			newOnLoadFn();
		}
	}
}

And call events using:

addOnLoadEvent(
	// declaration of function type
);

I would recommend anyone distributing scripts to make use of this to avoid conflicts with other event-triggered scripts users may have beside yours. Thanks!