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Hi, there is no simple way to do that and the exact behavior as described I can't emulate (today). I believe, that it's possible with deeper knowledge in perlXS, to access the exact codeline which throw the warning and extract their content. But you can define a signalhandler and use PadWalker to print out the lexical and global variables. The following example output these warnings:
Warning: Use of uninitialized value in concatenation (.) or string at mpu.cgi line 25.
Possible variables are:
          '$GLOBAL_VARIABLE' => \'global',
          '$t' => \undef,
          '$s' => \'regular output'
#!/usr/bin/perl use strict; use warnings; use PadWalker(); use Data::Dumper(); local $SIG{'__WARN__'} = sub { if($_[0] !~ /^Use of uninitialized value/) { print @_; } else { # If there are objects, the output can be VERY large when you +increase this local $Data::Dumper::Maxdepth = 2; # takes all lexical variables from caller-nemaspace my $possibles = Data::Dumper::Dumper({ %{PadWalker::peek_my(1) +}, %{PadWalker::peek_our(1)} }); $possibles ne "\$VAR1 = {};\n" ? ($possibles =~ s/^.*?\n(.*)\n +.*?\n$/$1/ms) : ($possibles = ''); print STDERR "Warning: " . join(', ', @_) . "Possible variable +s are:\n$possibles\n"; } }; our $GLOBAL_VARIABLE = 'global'; sub mySub { my $t = undef; my $s = "regular output"; print " $s $t "; } mySub();
Warnings abouot uninitialized values are resolved, all others behave like before. This you should use only to develop. Some warings about uninitialized variables can be very large, when the caller-namespace contain many variables. Tobiwan

In reply to Re: Debugging "Use of uninitialized value" warnings. by Tobiwan
in thread Debugging "Use of uninitialized value" warnings. by cwry

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    [Lady_Aleena]: Module is currently 104 lines but will shirnk to 63. The script using the module is currently 40 lines but will grow to 82, 180 to 146 lines total. (This is after rewrting the data files.)

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