review.tizen.org Git - platform/framework/web/crosswalk-tizen.git/blob

   1 define([
   2     '../array/forEach',
   3     '../function/identity',
   4     '../function/makeIterator_'
   5 ], function(forEach, identity, makeIterator) {
   6
   7     /**
   8      * Bucket the array values.
   9      */
  10     function groupBy(arr, categorize, thisObj) {
  11         if (categorize) {
  12             categorize = makeIterator(categorize, thisObj);
  13         } else {
  14             // Default to identity function.
  15             categorize = identity;
  16         }
  17
  18         var buckets = {};
  19         forEach(arr, function(element) {
  20             var bucket = categorize(element);
  21             if (!(bucket in buckets)) {
  22                 buckets[bucket] = [];
  23             }
  24
  25             buckets[bucket].push(element);
  26         });
  27
  28         return buckets;
  29     }
  30
  31     return groupBy;
  32 });