Carp croak not working when used in an imported function

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

I am importing a function called "errmsg" into my module. This function formats my error messages, specifically it handles dies. This function lives in a helper module.

The main module dies via "errmsg" when someone passes the wrong argument to a method.

The problem is that the error is always reported as happening in the module and not in the program that calls the method with the wrong argument. So I am trying to use Carp's croak function, but it is not working right.

In my "errmsg" function, I am using 'Carp::croak'. (I have to qualify it because CGI::Carp is also importing croak apparently.) Is there something I need to add to 'Carp::croak' to get it to report the error as I want it? Thanks. Example code:

sub errmsg {
Carp::croak "$_[0]";
}
[download]

Comment on Carp croak not working when used in an imported function Download Code

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Re: Carp croak not working when used in an imported function by ikegami (Patriarch) on Sep 29, 2006 at 23:10 UTC
Even though it's been imported (say into PkgB), `errmsg` was compiled in another package (say into PkgA). `croak` will skip over any calls within PkgA because that's where `errmsg` was compiled. It doesn't skip over the calls in PkgB. A couple of ways around this: `package PkgB; sub errmsg { local $Carp::CarpLevel = $Carp::CarpLevel + 1; PkgA::errmsg(@_); }` [download] or `package PkgB; our @ISA = 'PkgA';` [download] or `package PkgB; our @CARP_NOT = 'PkgA';` [download]	[reply] [d/l] [select]
Re: Carp croak not working when used in an imported function by mreece (Friar) on Sep 29, 2006 at 22:49 UTC
try this? `sub errmsg { local $Carp::CarpLevel = 1; Carp::croak "$_[0]"; }` [download] update: i understand this is a rather contentious 'feature'! some suggest ~~+=1~~ instead, or consider Carp::Clan.. again: +=1 doesn't work as i expected on a `local`, use `local $Carp::CarpLevel = $Carp::CarpLevel + 1;` as shenme suggested below!	[reply] [d/l] [select]
Re^2: Carp croak not working when used in an imported function by shenme (Priest) on Sep 29, 2006 at 23:04 UTC
Quick, before tilly notices, change that to `local $Carp::CarpLevel = $Carp::CarpLevel + 1;` [download]	[reply] [d/l]
Re^2: Carp croak not working when used in an imported function by fmerges (Chaplain) on Sep 29, 2006 at 23:25 UTC
Hi, Why quoting the parameter to croak? "$_[0]" -> $_[0] I don't see the problem: cucu.pm `package cucu; use strict; use Carp (); sub error { Carp::croak @_; } 1;` [download] t.pl `use strict; use cucu; ty(); sub ty { cucu::error('blabla'); }` [download] Regards, fmerges at irc.freenode.net	[reply] [d/l] [select]
Re^2: Carp croak not working when used in an imported function by Anonymous Monk on Sep 29, 2006 at 23:12 UTC
That did it! Thanks.	[reply]
Re: Carp croak not working when used in an imported function by diotalevi (Canon) on Sep 29, 2006 at 23:33 UTC
This is a problem that Carp::Clan solves. ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply]


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