small, simple, matcher function factory for searching DOM nodes

matcher

/** any tag  
 - () - any alement that is a tag and not TextElement
 - (func) - matching decided by the provided function
 - (tag) - element with that tag
 - (attr,value) - element with attribute and value for it
 - (tag,attr,value) */
function matcher(p1,p2,p3){
	if(typeof(p1) == 'function') return p1;
	if(!p3){
		if(!p2){	
			if(!p1) return function(e){ return e.tagName; };
			return function (e){ 
				return e.tagName == p1; 
			};
		}else{
			return function (e){ 
				return e.getAttribute && e.getAttribute(p1) == p2; 
			};
		}
	}else{
		return function (e){ 
			return e.getAttribute && e.tagName == p1 && e.getAttribute(p2) == p3; 
		};
	}
}