Is there an indexOf in javascript to search an array with custom compare function

Question

I need the index of the first value in the array, that matches a custom compare function.

The very nice underscorej has a \"find\" function that returns the

Answer 1

How about such find function ?

(function () {
  if (!Array.prototype._find) {
    Array.prototype._find = function (value) {
      var i = -1, j = this.length;
      if (typeof(value)=="function") 
         for(; (++i < j) && !value(this[i]););
      else
         for(; (++i < j) && !(this[i] === value););

      return i!=j ? i : -1;
    }
  }
}());