I would like to do some complex semantic operation, but I am not sure if it is possible to do with Spirit. At the moment it does'nt compile :-)
I want a rule like this inside a template class with Iterator, and ActionHandler as template names:
1: qi::rule< 2: Iterator, 3: qi::locals< 4: std::vector<typename ActionHandler::AClass *>, 5: typename ActionHandler::BClass> * 6: >, 7: skipper 8: > rule1;
later in the grammar I would like something like this:
9: rule1.name("rule1"); 10: rule1 = 11: ( 12: qi::lit("AClass") > 13: +(qi::int_ > qi::int_ > qi::char_)[ 14: qi::_a.push_back(phoenix::construct< 15: typename ActionHandler::AClass>(qi::_1, qi::_2, qi::_3) 16: ] > 17: -( 18: qi::lit("BClass") > 19: +(qi::int_ > qi::char_)[qi::_b.addPair(qi::_1, qi::_2)] 20: )[phoenix::for_each(qi::_a.begin(), qi::_a.end(), 21: xxx::a_element.setBClass(qi::_b))] 22: )[phoenix::bind(&ActionHandler::addAClassVector, 23: phoenix::ref(handler), qi::_a)] 24: ;
I guess I have some problem with: - The rule definition, here seems is expecting the rule's attribute type
Hmmm, I don't understand why you 'seem' to imply that.
- Line 14: - qi::_a is an actor, does'nt have push_back method
Sure, it has none such member. Just use phoenix::push_back(_a, ...) instead.
- construct returns a AClass pointer?
Use phoenix::new_<> instead of phoenix::construct<>.
- Line 19, same as befor, qi::_b is an actor without addPair method
Sure, why do you expect the placeholders to expose your member functions? Using phoenix::bind should do the trick.
- Line 20: - is it possible to use for_each?, I guess phoenix can.
Yes.
- begin/end qi::_a is an actors not a vector
It is possible. Again, placeholders don't know anything about your types. Use phoenix::begin() and phoenix::end().
Some idea to face it?, or may be is too complex and better do it in some other easier way?
Remember, all function calls inside a semantic action have to be lazy, i.e. have to be function objects with their parameters pre-bound. Often it is easier to write your own custom phoenix::functions encapsulating all the functionality than to build overly complex phoenix expressions, though. Regards Hartmut --------------- Meet me at BoostCon www.boostcon.com PS: Generally, posting a minimal (non-)compiling code helps answering the questions better.