use 5.010;
use strict;
use warnings;

my @a=qw(abc def);

given (@a) {
    when (/abc/  ) { say '/abc/';   continue; }
    when (qr/abc/) { say 'qr/abc/'; continue; }
}

say '--';

if (@a ~~ /abc/  ) { say '/abc/';   }
if (@a ~~ qr/abc/) { say 'qr/abc/'; }

##</code><code>##

qr/abc/
--
/abc/
qr/abc/