The following module was proposed for inclusion in the Module List:
modid: Carp::Clan
DSLIP: Rdpfp
description: Report errors f/ caller of "clan" of modules
userid: STBEY (Steffen Beyer)
chapterid: 2 (Perl_Core_Modules)
communities:
personal email
similar:
Carp
rationale:
This module is based on "Carp.pm" from Perl 5.005_03. It has been
modified to skip all package names matching the pattern given in the
"use" statement inside the "qw()" term (or argument list).
Suppose you have a family of modules or classes named "Pack::A",
"Pack::B" and so on, and each of them uses "Carp::Clan qw(^Pack::);"
(or at least the one in which the error or warning gets raised).
Thus when for example your script "tool.pl" calls module "Pack::A",
and module "Pack::A" calls module "Pack::B", an exception raised in
module "Pack::B" will appear to have originated in "tool.pl" where
"Pack::A" was called, and not in "Pack::A" where "Pack::B" was
called, as the unmodified "Carp.pm" would try to make you believe
:-).
This works similarly if "Pack::B" calls "Pack::C" where the
exception is raised, etcetera.
In other words, this blames all errors in the "Pack::*" modules on
the user of these modules, i.e., on you. ;-)
The skipping of a clan (or family) of packages according to a
pattern describing its members is necessary in cases where these
modules are not classes derived from each other (and thus when
examining @ISA (as in the original "Carp.pm" module) doesn't help).
The purpose and advantage of this is that a "clan" of modules can
work together (and call each other) and throw exceptions at various
depths down the calling hierarchy and still appear as a monolithic
block (as though they were a single module) from the perspective of
the caller.
In case you just want to ward off all error messages from the
module in which you "use Carp::Clan", i.e., if you want to make all
error messages or warnings to appear to originate from where your
module was called (this is what you usually used to "use Carp;" for
;-)), instead of in your module itself (which is what you can do
with a "die" or "warn" anyway), you do not need to provide a
pattern, the module will automatically provide the correct one for
you.
I.e., just "use Carp::Clan;" without any arguments and call "carp"
or "croak" as appropriate, and they will automatically defend your
module against all blames!
In other words, a pattern is only necessary if you want to make
several modules (more than one) work together and appear as though
they were only one.
So the module is backwards compatible to Carp from Perl 5.005_03
enteredby: STBEY (Steffen Beyer)
enteredon: Wed Oct 10 19:40:41 2001 GMT
The resulting entry would be:
Carp::
::Clan Rdpfp Report errors f/ caller of "clan" of modules STBEY
Thanks for registering,
The Pause Team
PS: The following links are only valid for module list maintainers:
Registration form with editing capabilities:
https://pause.perl.org/pause/authenquery?ACTION=add_mod&USERID=f3000000_5f5e1963219f7b69&SUBMIT_pause99_add_mod_preview=1
Immediate (one click) registration:
https://pause.perl.org/pause/authenquery?ACTION=add_mod&USERID=f3000000_5f5e1963219f7b69&SUBMIT_pause99_add_mod_insertit=1
