gistfile1.txt

Relevant IRC discussion: http://irclog.perlgeek.de/perl6/2016-04-25#i_12390649

I propose we add :captures argument to .comb sub/method that will modify the behavious to return a list of captures inside the given Matcher.

Consider this Perl 5 code:

    my %h = 'moo=meow ping=pong' =~ /(\w+)=(\w+)/g

It constructs a hash with keys `moo` and `ping` whose values are `meow` and `pong` respectively. To replicate the same behaviour in Perl 6, the simplest code I came up with asks .comb for Match objects, which through a series of hypers and coersions, it flattens into a list I can assign to a hash:

    my %h = 'moo=meow ping=pong'.comb(/(\w+) '=' (\w+)/, :match)>>.Slip.>>.Str

Not only is the code verbose, the coersions make it harder to understand that the goal is here. With my proposal in place, the above code will be simplified to:

    my %h = 'moo=meow ping=pong'.comb: /(\w+) '=' (\w+)/, :captures;

Another example could be picking data from text:

    my @rows = $ascii-table.comb: /^^ \s* (.?) \s* '|' \s* (.?) \s* '|' \s* (.?) \s* $$/, :captures;