is equivalent

No, it really isn't:

use strict;
use warnings;

use Test::More tests => 2;

my $in = "\N{LATIN SMALL LETTER C WITH CEDILLA}";

like ($in, qr{\A[A-Za-z0-9](?:[A-Za-z0-9_.-]*?[A-Za-z0-9]|)\z}, 'kcott
+');
like ($in, qr{ \A [[:alnum:]] (?: [[:alnum:]_.-]* [[:alnum:]])? \z }xm
+s, 'AnomalousMonk');

[download]

In reply to Re^3: Regex to detect file name by hippo
in thread Regex to detect file name by lirc201

Title:
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