public function on() : self
    {
        $this->handler->setErrorHandler();
        $this->handler->setExceptionHandler();
        $this->handler->setFatalHandler();

        return $this;
    }
public function on() : self
    {
        $this->handler->setErrorHandler();
        $this->handler->setExceptionHandler();
        $this->handler->setFatalHandler();

        return $this;
    }
public function on ( ) : self { $ this -> handler -> setErrorHandler ( ) ; $ this -> handler -> setExceptionHandler ( ) ; $ this -> handler -> setFatalHandler ( ) ; return $ this ; }
enable ouch error handler.

@return $this
enable ouch error handler .