I happened across Marco d'Itri's blog post regarding the s/// operator with the "g" option. I did a few tests, and I'm completely stumped. It seems like this is a bug. 
#!/usr/bin/perl

use strict;
use warnings;

my ($test, $count);

# WORKS
$test = <<'END';
ABCD
DEFG
END

$count = ($test =~ s/(BC?[DE])//gi);
print "Removed: <<$1>>\nCOUNT: $count\n";


# THIS ALSO WORKS
$test = <<'END';
ABCD
AEFG
END

$count = ($test =~ s/(BC?[DE])//gi);
print "Removed: <<$1>>\nCOUNT: $count\n";


# FAILS
$test = <<'END';
ABCD
ABFG
END

$count = ($test =~ s/(BC?[DE])//gi);
print "Removed: <<$1>>\nCOUNT: $count\n";

[download]
As soon as the two lines both begin with the same pair of characters, $1 is no longer defined. What am I missing here?
--rjk

In reply to Bug or feature? s/// and the g option by Belgarion

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