Solucion al ejercicio Concatenator #gejs

concatenator.js

var example=["hola",3,["soy",function(){}, ["juan", "fernandez"] ], "y",new Date(), ["no", "tengo",function(){},["dinero",[]] ] ];

/* Using .isArray ECMAS5
https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/isArray */
if(!Array.isArray) {
  Array.isArray = function (arg) {
    return Object.prototype.toString.call(arg) === '[object Array]';
  };
}

var concatena=function(obj,character){
	character = character || ',';
	var result='',partialResult,concatenator;
	if(typeof(obj)=='string'){
		return obj;
	}
	if (Array.isArray(obj)){
		for(var i=0,z=obj.length;i<z;i++){
			partialResult=concatena(obj[i],character);
			concatenator = i>0 ? character : '';
			if(partialResult!=''){
				result += concatenator+partialResult;
			}
		}
	}
	return result;
}

concatena(example,'-');