Perl::Critic::Policy::ErrorHandling::RequireCarping(3) Use functions from Carp instead of warn or die.


This Policy is part of the core Perl::Critic distribution.


The "die" and "warn" functions both report the file and line number where the exception occurred. But if someone else is using your subroutine, they usually don't care where your code blew up. Instead, they want to know where their code invoked the subroutine. The Carp module provides alternative methods that report the exception from the caller's file and line number.

By default, this policy will not complain about "die" or "warn", if it can determine that the message will always result in a terminal newline. Since perl suppresses file names and line numbers in this situation, it is assumed that no stack traces are desired either and none of the Carp functions are necessary.

    die "oops" if $explosion;             #not ok
    warn "Where? Where?!" if $tiger;      #not ok
    open my $mouth, '<', 'food'
        or die 'of starvation';           #not ok
    if (! $dentist_appointment) {
        warn "You have bad breath!\n";    #ok
    die "$clock not set.\n" if $no_time;  #ok
    my $message = "$clock not set.\n";
    die $message if $no_time;             #not ok, not obvious


By default, this policy allows uses of "die" and "warn" ending in an explicit newline. If you give this policy an "allow_messages_ending_with_newlines" option in your .perlcriticrc with a false value, then this policy will prohibit such uses.

    allow_messages_ending_with_newlines = 0

If you give this policy an "allow_in_main_unless_in_subroutine" option in your .perlcriticrc with a true value, then this policy will allow "die" and "warn" in name space main:: unless they appear in a subroutine, even if they do not end in an explicit newline.

    allow_in_main_unless_in_subroutine = 1


Should allow "die" when it is obvious that the ``message'' is a reference.


Jeffrey Ryan Thalhammer <[email protected]>


Copyright (c) 2005-2011 Imaginative Software Systems. All rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license can be found in the LICENSE file included with this module.