original_string: public function sortByKeys( \Closure $callback )
  	{
  		$items = $this->items;
  		uksort($items, $callback);
  		return new static($items);
  	}
code: public function sortByKeys( \Closure $callback )
  	{
  		$items = $this->items;
  		uksort($items, $callback);
  		return new static($items);
  	}
code_tokens: public function sortByKeys ( \ Closure $ callback ) { $ items = $ this -> items ; uksort ( $ items , $ callback ) ; return new static ( $ items ) ; }
docstring: Sort an collection by keys using a user-defined comparison function
  
  @param \Closure $callback
  @return static
docstring_tokens: Sort an collection by keys using a user - defined comparison function