You need to do when (qr/abc/). when(/abc/) appears to do when($_ ~~ ($_ =~ /abc/)). 
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/'; }

[download]
qr/abc/
--
/abc/
qr/abc/

[download]
The discrepency is odd, though.

In reply to Re^5: Smart enough for Smart Match??? (was "Understanding ...Given/When" ) by ikegami
in thread Understanding the benefit of Given/When ... by LanX

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