You can use some trickery and get the warning to kick the debugger into single-step mode:

use strict;
use warnings;

$SIG{__WARN__} = sub { $DB::single = 1 };

my $c = 3;
my $d = 'foo';

my $e = $c + $d;
print "$e\n";

[download]

This will stop the program after the warning that caused the error (the addition of $c and $d). It is a much more difficult proposition to stop the program before the warning. Then again, this is probably sufficient 99.99% percent of the time.

Note that you still have to run the program under the debugger: perl -d myprogram. The gain is that you just have to <r>un the program, and it will churn away until a warning is raised.

• another intruder with the mooring in the heart of the Perl

In reply to Re: break on warning in debugger by grinder
in thread break on warning in debugger by confused_newbie

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