the errors method

Bricklayer template tag handlers also inherit the errors method. This method allows you to do logging and error handling using Bricklayers error handling API. If you have specialized error handler plugins they will be used. The method is called with the following syntax ->errors("error text", "error_type") where the text is the logging or error message you wish to use and the type is an error or logging level. Bricklayer natively understands the following levels: log and fatal. log is just a system logging message and fatal causes bricklayer to generate an error message and stop running. If you write error handlers that understand other levels you can use them too.