code: function(a, b) {
        var found = 0
          , keys = Object.keys(b)
          , i = 0
          , l = keys.length
          , val;
  
        for (; i < l; i++) {
          val = b[keys[i]];
          if (has(a, val)) found++;
        }
  
        return found === l;
      }
docs: contains all...