I've started playing with the named capture and grammar features of 5.10. I like what I see, but I did find something that stumped me.

If I use a named capture I get what I expect: 

#!/usr/local/bin/perl
use strict;
use warnings;

use Data::Dumper;

my $number_re = qr{
    (?<int>  \d+)
}x;

my $num = 15;
if ( $num =~ /^$number_re$/ ) {
    warn "'$num' is valid\n";
    warn Dumper( \%- );
}

# produces: 
#'15' is valid
#$VAR1 = {
#          'int' => [
#                     '15'
#                   ]
#        };

[download]
But, when I try to DEFINE a grammar, the named capture only stores undef: 
#!/usr/local/bin/perl
use strict;
use warnings;

use Data::Dumper;

my $number_re = qr{
    (?(DEFINE)
      (?<int>          \d+ )
    )
    (?&int)
}x;

my $num = 15;
if ( $num =~ /^$number_re$/ ) {
    warn "'$num' is valid\n";
    warn Dumper( \%- );
}

# produces:
#'15' is valid
#$VAR1 = {
#          'int' => [
#                     undef
#                   ]
#        };

[download]
Am I missing something?

(Perhaps my excitement at the new grammar features has raised my expectations too high. I was starting to hope for a parse tree.)

Phil

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In reply to 5.10 named capture in DEFINE regex by philcrow

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