exploring javascript type auto-coercion (and its pitfalls)

gistfile1.txt

// **********
// NOTE: this is a stupid trivial example illustrating automatic
// type-coercion, not an example of the kind of data-structure logic
// you'd ever actually use. don't miss the forest for the trees.
// Read down in the comment thread for 'myCoolString' for a slightly
// more sensible example.
//
// NOTE #2: this gist thread was spawned from a twitter discussion
// about `parseInt(0/1,19)==18`:
// https://twitter.com/getify/status/221009838006747136
// **********


var myObj = {
   _val: [10,5,7,9,-1,4,13,6],
   toString: function(){
     return ""+Math.max.apply(this,this._val);
   }
};

parseInt(myObj); // 13 ==> this is part of what makes javascript awesome

I woud use valueOf here instead of toString.