Using lex/yacc I can do a more or less complex things in .yacc semantic actions, such complex as bytecode compilation or real CPU assembly.

Playing with pegged, I can't figure out how to move from ParseTree to such like semantic actions. I even can't parse numbers from strings in lexer-like rules because it looks like every rule runs on any token parse, or sumething like this.

Also, I use attribute object trees resemble attribute grammar both for parsing and internal code representation:

class Object {
  string               value; // or `int value` and `float value` for numbers
  map<string, Object*> attr;
  vector<Object*>      nested;
}

And I also can't figure out how to inherit ParseTree with all my script language objects to get AST right from pegged parser. Should I use some superloop with lot of matches to process parsed pt tree into something I need myself, to drop all unneeded parsing meta info and get clean semantic AST?