Parse Flags

use v6;

my %all-flags := {};

grammar OptionsParser {
    rule TOP {
        ^^ ('-' <flag-with-values>)+ %% <.ws> $$
    }

    token flag-with-values {
        <flag-name> <.ws> <flag-value>
    }
    
    token flag-name {
        <alnum>+
    }

    token flag-value {
        <[a..zA..Z0..9\-]>+
    }
}

class OptionsParserActions {
    method flag-with-values($/) {
        my ($flag-name, $flag-value) = ($/<flag-name>.Str, $/<flag-value>.Str);
        %all-flags{$flag-name} = $flag-value;
    }
}

sub parse-options($flags) {
    OptionsParser.parse(@*ARGS.join(' '), :actions(OptionsParserActions));
    %all-flags;
}

DOC CHECK {
    use Test;

    subtest "Test case" => {
        my $input = <-a 1 -b 2 -c a-b-c -d four>;
        parse-options($input).&is({ 'a' => '1', 'b' => '2', 'c' => 'a-b-c', 'd' => 'four' });
    }
}