original_string: public function keys()
      {
          $map = new Map;
          foreach (array_keys($this->array) as $hash) {
              $map[] = $this->hash_to_key($hash);
          }
          return $map;
      }
code: public function keys()
      {
          $map = new Map;
          foreach (array_keys($this->array) as $hash) {
              $map[] = $this->hash_to_key($hash);
          }
          return $map;
      }
code_tokens: public function keys ( ) { $ map = new Map ; foreach ( array_keys ( $ this -> array ) as $ hash ) { $ map [ ] = $ this -> hash_to_key ( $ hash ) ; } return $ map ; }
docstring: Get the keys of this map as a new map.
  
  @return new Map
  @api
  @since 1.0.5
docstring_tokens: Get the keys of this map as a new map .