So we have named captures and it's not much time since we do, but I already ask for them not to be read-only: what people tell me basically is that there are implementation details that force them to be instead. Now I go one step further so this may well be taken as sci-fi, but nevertheless I think it exposes an interesting idea: from 5.10 onward we have a lexical $_ so I wonder whether we could have lexical %+ and %- such that:

• their entries would not be reset across matches until the end of the lexical scope they live in;
• (they would be modifiable - I still insist on that!)

Thus one may have the following example (which explains the whole thing better than many abstract descriptions...) working as naively expected:

{
    my %+;
    doit if $x ~~ / (?<x1> \w+)\s+(?<x2> \w+) /x and
            $y ~~ / (?<y1> \w+)\s+(?<y2> \w+) /x and
            $+{x1} . $+{y2} eq $+{y1} . $+{x2};
}
[download]

$x = 'fo  ar!';
$y = '?foob obar  ar';
[download]

$VAR1 = {
          'y1' => 'foob',
          'x2' => 'ar',
          'y2' => 'obar',
          'x1' => 'fo'
        };
[download]

Please don't point out that wrt the example above there are tons of other WTDI: it's obvious that there are - we're talking about Perl anyway! I just think we could have one more, and with a very clear syntax too. Also, the idea sprang in the context of that other thread dealing with %+ and %- but there may be other special variables that may allow a lexical incarnation with a modified semantics associated to to it.