UPDATE: I have since wrapped all my logging gubbins in custom $SIG{__DIE__} and $SIG{__WARN__} handlers.

use Log::Log4perl qw/:easy :no_extra_logdie_message/;
$SIG{__DIE__} = sub {
        return if $^S; # ignore die in an eval block
        
        # Get the actual caller for the "die" and not the wrapper
        local $Log::Log4perl::caller_depth;
        $Log::Log4perl::caller_depth++;
        
        LOGDIE($_[0]);
    };
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I am currently working on implementing Log::Log4perl in one of my scripts. I have never used this before, and I would like some advise/critiques please.

perl -v
This is perl 5, version 16, subversion 3 (v5.16.3) built for MSWin32-x
+86-multi-thread
(with 1 registered patch, see perl -V for more detail)

Copyright 1987-2012, Larry Wall

Binary build 1603 [296746] provided by ActiveState http://www.ActiveSt
+ate.com
Built Mar 13 2013 11:29:21
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1. I wrote a logging wrapper in $SIG{__DIE__} so I would not have to hunt down and replace all of my die(...) calls with $log->logdie(...)

   $SIG{__DIE__} = sub {
       my ($message) = @_;
       chomp $message;
   
       # Get the actual caller for the "die" and not the wrapper
       local $Log::Log4perl::caller_depth;
       $Log::Log4perl::caller_depth++;
   
       my $log = get_logger('');
       $log->logdie($message);
   };
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2. This broke all my eval{...} error handling:
   

   # the new $SIG{__DIE__} causes everything to die here:
   eval{ do_something(\@args) or die "'do_something()' failed: $!"; };
   
   # This never gets reached
   if ( $@ ) {
       warn "Could not do_something(): [$@]";
       something_else();
   }
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3. $SIG{__DIE__} also catches errors in other modules. I discovered this when I was working with YAML.pm:
   

   use YAML qw/LoadFile/;
   
   # dies with the following error:
   # Can't locate Mo/builder.pm in @INC (@INC contains: C:/Perl/site/lib 
   +C:/Perl/lib .) at (eval 65) line 2, <$IN> line 1.
   my $yaml = LoadFile('./config.yml');
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   (I fixed this particular issue by installing Mo via ppm, but it appears I have opened my self up to a veritable minefield...)
   
   
4. I discovered the $^S variable on perlvar and how it can be used to selectively disable die() in an eval{...} block:

   $SIG{__DIE__} = sub {
       return if $^S; # ignore die in an eval block
       ...
   };
   [download]

   This appears to work the way I expect, but the %SIG and $^S sections in perlvar and the die section in perldoc has some dire sounding warnings about this. (e.g. "Having to even think about the $^S variable in your exception handlers is simply wrong. $SIG{__DIE__} as currently implemented invites grievous and difficult to track down errors."). I am inexperienced enough to be worried about this.

With all that being said, is there a better way to write a Log4perl wrapper for my script's existing die() calls?

Thank you for your time

#!/usr/bin/perl
use Log::Log4perl qw/get_logger :no_extra_logdie_message/;
use strict;
use warnings;
use YAML qw/LoadFile/;

CHECK {
LOG_INIT: {
    # Initialize logging
    local $/ = undef;
    Log::Log4perl::init(\<DATA>);
}
LOG_WRAPPERS: {
    # Wrapper for logging fatal errors
    $SIG{__DIE__} = sub {
        #return if $^S; # ignore die in an eval block
        my ($message) = @_;
        chomp $message;

        # Get the actual caller for the "die" and not the wrapper
        local $Log::Log4perl::caller_depth;
        $Log::Log4perl::caller_depth++;

        my $log = get_logger('');
        $log->logdie($message);
    };
}
}

####################
## MAIN
{
    #Can't locate Mo/builder.pm in @INC (@INC contains: C:/Perl/site/l
+ib C:/Perl/lib .) at (eval 65) line 2, <$IN> line 1.
    my $yaml = LoadFile('./path/to/yaml/file.yml') or die "Could not p
+arse config file:\n$!\n$^E";

    eval { die "a hot potato"; }; # dies here
    if ($@) { print "I caught something:\n[$@]"; exit; } # this is nev
+er reached
}

__DATA__
layout_class = Log::Log4perl::Layout::PatternLayout

# Layout for screen logging
# [Priority] [File::Caller] [Line Number] > Message
debug_layout_pattern = [%p] [%F{1}::%M] [%L] > %m %n

##
## LOGGERS
##
log4perl.logger = TRACE, LogScreen

# Logging to screen
# (Includes TRACE and DEBUG priority level messages)
log4perl.appender.LogScreen         = Log::Log4perl::Appender::Screen
log4perl.appender.LogScreen.utf8    = 1
log4perl.appender.LogScreen.layout  = ${layout_class}
log4perl.appender.LogScreen.layout.ConversionPattern = ${debug_layout_
+pattern}
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