gistfile1.txt

$ cat ABC.pm 

grammar ABC::Grammar is HLL::Grammar {
	rule TOP { <expr> }
	rule expr { <integer> <addop> <integer> };
	token addop { '+' | '-' }
	token integer { \d+ }
}

class ABC::Actions is HLL::Actions {

	method TOP($/) { make $<expr>.ast; }

	method expr($/) { 
		my $pirop := $<addop> eq '-' ?? 'sub' !! 'add';
		make PAST::Op.new( :pirop($pirop), +$<integer>[0], +$<integer>[1]);
	}
}

class ABC::Compiler is HLL::Compiler {
	ABC::Compiler.language('ABC');
	ABC::Compiler.parsegrammar(ABC::Grammar);
	ABC::Compiler.parseactions(ABC::Actions);
}

my @ARGS := (pir::getinterp__p)[2];
ABC::Compiler.command_line(@ARGS);

$ ./nqp ABC.pm --target=parse
> 1 + 2
"parse" => PMC 'Regex;Match' => "1 + 2\n" @ 0 {
    <expr> => PMC 'Regex;Match' => "1 + 2\n" @ 0 {
        <integer> => ResizablePMCArray (size:2) [
            PMC 'Regex;Match' => "1" @ 0,
            PMC 'Regex;Match' => "2" @ 4
        ]
        <addop> => PMC 'Regex;Match' => "+" @ 2
    }
}

$ ./nqp ABC.pm 
> 1 + 2
Method 'ast' not found for invocant of class 'Undef'