protected function parseDocControlLine( Line$line ):self
	{
		switch( $name= $line->pregGet('/(?<=^@)[\w-:]+/') ){
			default:{
				$this->throw("The @$name is not supported.");
			}break;
			case 'extend':{
				$this->throw('The @extend can only be used on first line.');
			}break;
			case 'include':{
				$this->include($line);
			}break;
			case 'section':{
				$this->defineSection($line);
			}break;
			case 'show':{
				$this->showSection($line);
			}break;
		}

		return $this;
	}