docs: function iterateFilter(input) {
    var self = this,
      out = {};
  
    if (utils.isArray(input)) {
      return utils.map(input, function (value) {
        return self.apply(null, arguments);
      });
    }
  
    if (typeof input === 'object') {
      utils.each(input, function (value, key) {
        out[key] = self.apply(null, arguments);
      });
      return out;
    }
  
    return;
  }