maybe?

use v5.12;
use warnings;
use Data::Dump qw/pp dd/;

my $input = join "|", qw/Monday Saturday Thursday/;
my @order = qw/monday tuesday wednesday thursday friday saturday sunda
+y/;


pp grep { /^($input)$/i } @order;

[download]

==>

("monday", "thursday", "saturday")

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: Challenge: sort weekdays in week-order (grep) by LanX
in thread Challenge: sort weekdays in week-order (elegantly and efficiently) by bliako

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