jlUtil For Javascript

var jlUtil = {
	getJSON: function(obj, skip_arr){
		if(typeof obj == "number"
		|| typeof obj == "boolean"){
			return obj;
		}else if(typeof obj == "string"){
			return "'" + obj.replace("'","\\'") + "'";
		}
 
		var json = [];
		skip_arr = skip_arr ? skip_arr : [];
		for(var key in obj){
			//skip function and the keys in skip arr
			if(obj[key].constructor == Function
			|| skip_arr.indexOf(key) != -1){
				continue;
			}
 
			//in Array loop
			if(!isNaN(parseInt(key)) || key.constructor != String){
				json.push(jlUtil.getJSON(obj[key], skip_arr));
				continue;
			}
 
			//else recurrency
			json.push("'" + key + "':" + jlUtil.getJSON(obj[key], skip_arr));
		}
 
		if (obj.constructor == Array) {
			return "[" + json.join(",") + "]";
		} else {
			return "{" + json.join(",") + "}";
		}
	},
	extend: function(obj){
		if (arguments.length == 1) {
			this.extend(this, obj);
			return this;
		}else if(arguments.length >= 2){
			var dst = arguments[0];
			//extend the rest args to args[0]
			for(var i=1; i<arguments.length; ++i){
				for(var item in arguments[i]){
					var tmp = arguments[i][item];
					if(typeof arguments[i][item] == "object"){
						//make a copy while is a object, needs jQuery here
						var tmp = $.extend({}, arguments[i][item]);
					}
					//if is object try recurrency
					if(dst[item] && typeof dst[item] == "object"){
						try{
							this.extend(dst[item], tmp);
						}catch(e){
							dst[item] = tmp;
						}
					}else{
						dst[item] = tmp;
					}
				}
			}
			return dst;
		}
	}
};