dist/underscore-contrib.js
function(array, pred) {
      return _.filter(_.map(_.range(_.size(array)), function(i) {
        return pred(i, array[i]);
      }),
      existy);
    }
function(array, pred) {
      return _.filter(_.map(_.range(_.size(array)), function(i) {
        return pred(i, array[i]);
      }),
      existy);
    }
function ( array , pred ) { return _ . filter ( _ . map ( _ . range ( _ . size ( array ) ) , function ( i ) { return pred ( i , array [ i ] ) ; } ) , existy ) ; }
Runs its given function on the index of the elements rather than the elements themselves, keeping all of the truthy values in the end.
Runs its given function on the index of the elements rather than the elements themselves keeping all of the truthy values in the end .