posix barrier-like functionality for events

barrier.js

// js barrier, waits for all events to be fired before executing the callback
// dependencies: 
// 1. jquery 1.4.2+  - jquery.com
// 2. ben alman's tiny jquery pub/sub  - https://gist.github.com/661855
(function($){
	$.barrier = function( evs , callback ){
		var events = evs.split(' ') ;
		var flags = {} ;
		var collector = {} ;
		$.each( events , function( i, ev ){
			flags[ev] = false ;
		}) ;
		$.each( events , function( i, ev ){
			$.subscribe( ev, function( data ){
				collector[ev] = data ;
				flags[ev] = true ;
				var finnish = true ;
				$.each( flags, function( f ){
					finnish = ( flags[f] !== false );
				}) ;
				if( finnish === true ){
					callback( collector ) ;
				}
			}) ;
		}) ;
	} ;
})(jQuery) ;