After compiling:
- remove all references to:
    Data::Bind
- replace the header with:
    package Pugs::Grammar::Rule;
    no strict 'refs';
    use Pugs::Runtime::Match;
    use Pugs::Runtime::Regex;
    our %rule_terms;
    our %variables;
- replace:
        $named{'concat'} = $match;
   - with:
        push @{ $named{'concat'} }, $match;