A lightweight jQuery memoizer for caching the results of expensive DOM operations.

jquery.cacheOf.js

// jQuery.fn.cacheOf - By Jed Schmidt (MIT Licensed)

// A lightweight jQuery memoizer for caching the results of expensive DOM operations.
	
//	Example usage:

// Say you have a processing-intensive call
// that occurs often in your code.

$().find( "*:not(:contains(abc))" );	
										
// Just initialize cacheOf with the method(s)
// for which results should be cached.

$.fn.cacheOf("find");

// Then make the same call, but inject the cacheOf
// method to fetch the results and cache them.

$().cacheOf().find( "*:not(:contains(abc))" );

// The next time you make the same call, the results
// will be pulled from cache instead of from the DOM.

$().cacheOf().find( "*:not(:contains(abc))" );

// You can cache whatever methods you want.
// Just use spaces to separate each one.

$.fn.cacheOf("find offset myFunc");

// Arguments are automatically hashed to memoize
// each unique call.

$("#myId").cacheOf().myFunc( 123, "abc", document.body );

// jQuery's native data storage is used, so all
// cached values for a node are cleared upon removal.

$("#myId").data("cacheOf"); // => returns an object with all cache keys

// You can also expire a node's cache manually.
$("#myId").cacheOf( null );	

// Questions? Find me at http://twitter.com/tr4nslator.
	
jQuery.fn.cacheOf = ( function() {

	var methods;
	
	return function() {

		if ( this.length === undefined )
			return methods = arguments[0].split(" ");
	
		if ( arguments.length )
			return this.removeData( "cacheOf" );
			
		var	ret = {}, cache = this.data( "cacheOf" );
			
		if ( !cache )
			this.data( "cacheOf", cache = {} );
			
		for ( var i in methods )
			ret[ methods[i] ] = bind( this, methods[i] );
		
		return ret;
		
		function bind( context, name ) {
			return function() {
				var	key = hash( [].concat.apply( [ name ], arguments ) );
				
				return cache[ key ] === undefined
					? cache[ key ] = jQuery.fn[ name ].apply( context, arguments )
					: cache[ key ];
			};
		};
		
		function hash( items ) {
			return jQuery.map( items, function( x ) {
				return x.nodeType ? jQuery.data( x ) : x;
			}).join();
		};
	}
})()