6.16.1 Signalling errors

Function: error string arg ...

[SRFI-23] Signals an error. Internally the action is realized by those two steps.

1. An error exception is created, with the message prefixed by string and followed by args.
2. The error exception is thrown, which may be handled by the current active error handler, if any.

If no error handler is active, the default error handler is used, which prints the error message to the current error port and some debug information. Then, if Gauche is running interactively, the control moves to the toplevel; if Gauche is running as a script, it exits with the exit status EX_SOFTWARE (70).

Function: errorf fmt-string arg ...

Similar to an error, but the error message is formatted by format, i.e. it is equivalent to:

(define (errorf fmt . args) (error (apply format #f fmt args)))