I thought the same. I think a nice name of the hash would be %~. =~ is matching so why couldn't $~{name} be a named match. Here is the code I ended up with: 

...
sub convert
{
    my $re = shift;
    $re =~ s( \\ ( \\ | C\{ (?>\s*) ((?>\w+)) (?>\s*) \} ) )
            {
                defined $2
                ? "(?{\$~{$2}=\$^N})"
                : "\\"
            }xeg;
    "(?{undef(%~)})" # clear the %~
    .$re
    ."(?{\$~{\$_}=\${\$_} for(1..\$#+)})"; # add the numbered matches
}
...

my $re = qr/(\w+)\C{baz}(?: - (\w+)\C{qux})?(\+\d+)/;

"three - four - five+89" =~ $re;
print "baz=$~{baz}, qux=$~{qux}, $~{3}\n";

[download]
Please note that even the named matches got their number! Maybe they should not, I think I could implement that if I needed.

I also considered syntax like this:

my $re = qr/(?\$bar=\w+) - (?\$qux{not}=\w+)/;

[download]
which could naively be implemented like this:
...
sub convert
{
    my $re = shift;
    $re =~ s<\(\?\\\$([^=]+)=([^)]*)\)><($2)(?{\$$1=\$^N})>g;
    $re
}
...

[download]
but the problem is that I don't know how to make sure you can do even things like :
my $re = qr/...(?\$var=a(\d+|\w-\w+)b).../;

[download]
I don't know how to find the right closing bracket.

Jenda
We'd like to help you learn to help yourself
Look around you, all you see are sympathetic eyes
Stroll around the grounds until you feel at home
   -- P. Simon in Mrs. Robinson

In reply to Re^3: RFC: named pattern match tokens by Jenda
in thread RFC: named pattern match tokens by revdiablo

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