I think my original code when I was testing was something along the lines of:

print re_strictness qr/.../, "\n";

[download]

In which case the ($) prototype helps Perl see the "\n" as a parameter for print, not for re_strictness.

By the way, it's worth pointing out that qr/^Dad+y$/ is also considered slightly stricter than qr/Dad+y/.

use 5.014;
use strict;
use warnings;
use re ();
use List::Util 'sum';

sub re_strictness ($) { sum map length, re::regmust shift }

print
    re_strictness qr/^Dad+y$/, "\n",
    re_strictness qr/Dad+y/, "\n",
    re_strictness qr/D.+/, "\n",
;

[download]
package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

In reply to Re^3: how to measure strictness of a regex ? by tobyink
in thread how to measure strictness of a regex ? by didess

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