my $parser = new Parse::RecDescent (q[
    functiondefine: /function/i name "(" parameters[$item[1]](?) ")" "{"
    name:           /[A-Za-z][a-zA-Z0-9_]*/
    parameters:     parameter[$arg[0]] ',' parameters[$arg[0]] { [@item[1,3]] }
                  | parameter[$arg[0]] { [$item[1]] }
    parameter:      name /as/i variabletype { [@item[1..$#item]] }
    variabletype:   /variant|array|keyarray/i
]);