If I understand you, just have your subroutine change a global variable to be the error message, then look at that on an undef return. You can make it a list if you want to report more than one error. You also might want to look into the <error:...> directive for the grammar.

-- Randal L. Schwartz, Perl hacker

In reply to Re: RecDescent error handling by merlyn
in thread RecDescent error handling by dcorbin

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