[perl #96424] NULL PMC on unmatched or non existent named capture

[Patrick R. Michaud via RT]

On Sun Aug 07 12:25:15 2011, ronaldxs wrote:
> Seems at least partially fixed in nom but still may be related 
concerns 
> like
> 
> nom: my $m = '34' ~~ /<digit>+|<alpha>+/; say $m<alpha>.perl; say 
> Nil.perl; my $x = $m<alpha> // 4; say 'x is ', $x
> nom: OUTPUT«()␤Nil␤x is ␤»
> 
> See http://irclog.perlgeek.de/perl6/2011-08-07#i_4239512

Since <alpha> is quantified here, it's guaranteed to be a (possibly 
empty) Array in the match object -- so nom has this one correct.

In the non-quantified case, nom is currently returning "Any", which 
seems reasonable:

    21:00 <pmichaud> nom: my $m = '34' ~~ /<digit>|<alpha>/;  say 
$m<alpha>.perl
    21:00 <p6eval> nom: OUTPUT«Any␤»

I'll likely close this ticket when nom becomes master, unless there's 
something wrong with my analysis above.

Pm