I'm doing an overhaul on one of my modules (I'm running v5.22.0) and am hitting "Unescaped left brace in regex is deprecated" in a mock script meant to be transformed into a unit test. The offending line is the fourth-from-last, because $_ has a { in it.

How can I escape or otherwise work around this issue, so it'll be backward and forward compatible?

#!/usr/bin/perl
use warnings;
use strict;

use File::Copy;
use Tie::File;

my $f = 't/sample.data';
my $wf = 't/write_sample.data';

copy($f, $wf);

tie my @wfh, 'Tie::File', $wf;

for (@wfh){
    if (/sub seven/){
        $_ =~ s/seven/xxxxx/;
    }
}

untie @wfh;

open my $wfh, '<', $wf
  or die "Can't open test written file $wf: $!";

open my $fh, '<', $f
  or die "Can't open original test file $f: $!";

my @wf = <$wfh>;
my @f = <$fh>;

for (@f){
    if (! grep /$_/, @wf){
        print "$_\n";
    }
}

[download]

-stevieb

In reply to "Unescaped left brace in regex is deprecated" by stevieb

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