Hello szabgab,

I actually like your own proposed solutions. But here is another possibility:

use 5.010;
use strict;
use warnings;
use constant DEBUG => 1;
no  if DEBUG, warnings => 'uninitialized';

my $x = 23;
my $y;

say "With DEBUG = ", DEBUG;

debug("x='$x' y='$y'") if DEBUG;

if (DEBUG)
{
    sub debug { say shift; }
}
[download]

Output:

22:41 >perl 1758_SoPW.pl
With DEBUG = 0

22:41 >perl 1758_SoPW.pl
With DEBUG = 1
x='23' y=''

22:41 >
[download]

The downside, of course, is that you have to add if DEBUG to the end of all your existing debug calls. :-(

Anyway, hope that helps,