$ node
> if(!Object.prototype.try) {
...   Object.prototype.try = function() {
...     if (typeof this[arguments[0]] == "undefined") return false;
...     return this[arguments[0]];
...   }
... }
[Function]
> 
> var objeto = {meuArray: [1,2]};
> console.log((objeto.try('meuArray').length > 0) ? "lindo": "feio");
lindo
> delete objeto.meuArray;
true
> console.log((objeto.try('meuArray').length > 0) ? "lindo": "feio");
feio
>