I found myself using cluck() today. Nothing wrong about that, except I couldn't find a nice way to ditch it for perl -d. I'm trying to see how to schedule/stop for a stack trace in this situation, with the debugger: 

sub message_id($)
{
    my $tr = shift; defined $tr or cluck(), return undef;
    $tr->isa('HTML::Element')   or return undef;
    my $td = ($tr->content_list())[0];
    return $td->as_trimmed_text();
}

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This function is called hundreds of times, I only want a backtrace when it's about to return in that specific condition.
(and yeah, I know cluck works perfectly there).

Thanks in advance

In reply to Translate debug code to a debugging technique by hlen

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