The other possible output would be -4294967294. The result depends on whether m// returns 0 or 1.

use strict;
use warnings;

my $file = "blah";

$_ = "kba.gz";
my $file =-~ /kba\.gz$/;
print $file, "\n";

$_ = "abcd";
my $file =-~ /kba\.gz$/;
print $file;
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