Question

I’m looking for something similar to Groovy’s every() method, which tests every element of a list if it meets some criteria. If they all meet the criteria, the function returns true. Otherwise, false. I’ve tried something like this:

var arr = [1, 0, 1, 0, 1, 1];
var allOnes = $.grep(arr, function(ind) { 
                   return this == 1;
               }).length == arr.length;

..but its not very clean. I haven’t had any luck while searching through the API. Is using grep() the only way to do it?

Answer 1

How about just turning your working code into a method on array, to ease its reuse:

Array.prototype.every = function(predicate){
 return $.grep(this,predicate).length == this.length;  
}

usage:

alert([1,0,1,0].every(function(i) { return i == 1; }));

Working example: http://jsfiddle.net/59J5A/

Edit: changed to grep