// Copyright (c) 2008-2023 the Urho3D project // License: MIT #pragma once // WRAP_MFN_PR for GCC // GCC has problems with templates, VS with macros, so implementations is different /* struct A { bool f(int i) { return true; } }; struct B : public A { // f() is inherited }; template struct WrapF { }; WrapF<&B::f> a; // Doesn't work for any compiler // Error: non-type template argument of type 'bool (Urho3D::A::*)(int)' cannot be converted to a value of type 'bool (Urho3D::B::*)(int)' WrapF(&B::f)> b; // Works for VS but not works for GCC // Error: non-type template argument is not a pointer to member constant ================================== MACROS1(a, b, MACROS2) GCC replaces the parameter MACROS2 first and after that MACROS1 VS replaces MACROS1 first VS has parameters: https://docs.microsoft.com/en-us/cpp/preprocessor/preprocessor-experimental-overview https://docs.microsoft.com/en-us/cpp/build/reference/experimental-preprocessor but it cause banch of errors in Windows 10 SDK <= 10.0.17763.0 and third party libs */ #ifndef _MSC_VER #include #include //only Boost.Preprocessor is needed, so it may be reasonable to include it in the Urho repository directly #include //Return void enable if: http://stackoverflow.com/questions/12002447/template-method-enable-if-specialization //# do with // http://stackoverflow.com/questions/5588855/standard-alternative-to-gccs-va-args-trick #define EV(...) __VA_ARGS__ #define UNWRAP(...) __VA_ARGS__ #define EXTRACT_CONST(...) (__VA_ARGS__), // from http://stackoverflow.com/questions/18851889/boost-preprocessor-skip-if-variadic-is-empty // based on the: http://gustedt.wordpress.com/2010/06/08/detect-empty-macro-arguments #define __ARG16(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, ...) _15 #define __HAS_COMMA(...) __ARG16(__VA_ARGS__, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0) #define __TRIGGER_PARENTHESIS_(...) , #define __PASTE5(_0, _1, _2, _3, _4) _0 ## _1 ## _2 ## _3 ## _4 #define __IS_EMPTY_CASE_0001 , #define __IS_EMPTY(_0, _1, _2, _3) __HAS_COMMA(__PASTE5(__IS_EMPTY_CASE_, _0, _1, _2, _3)) #define TUPLE_IS_EMPTY(...) \ __IS_EMPTY( \ /* test if there is just one argument, eventually an empty one */ \ __HAS_COMMA(__VA_ARGS__), \ /* test if _TRIGGER_PARENTHESIS_ together with the argument adds a comma */ \ __HAS_COMMA(__TRIGGER_PARENTHESIS_ __VA_ARGS__), \ /* test if the argument together with a parenthesis adds a comma */ \ __HAS_COMMA(__VA_ARGS__ (/*empty*/)), \ /* test if placing it between _TRIGGER_PARENTHESIS_ and the parenthesis adds a comma */ \ __HAS_COMMA(__TRIGGER_PARENTHESIS_ __VA_ARGS__ (/*empty*/)) \ ) #define __GEN_EMPTY_ARGS(...) #define __GEN_NONEMPTY_ARGS_CB(unused, data, idx, elem) \ , static_cast *>(gen->GetAddressOfArg(idx))->value #define __GEN_NONEMPTY_ARGS(seq) \ BOOST_PP_SEQ_FOR_EACH_I( \ __GEN_NONEMPTY_ARGS_CB \ ,~ \ ,seq \ ) #define CreateGenericFromMethod_2(...) EV(CreateGenericFromMethod_3(__VA_ARGS__)) #define CreateGenericFromMethod_3(class_t,method,parameters,const,return_t) \ asFunctionPtr([] (asIScriptGeneric* gen) {\ BOOST_PP_CAT(wrap::call,const) \ (gen,/*&(Proxy::cast(gen->GetObject()))*/((class_t*)gen->GetObject()), static_cast(&class_t::method)\ BOOST_PP_IF( \ TUPLE_IS_EMPTY parameters \ ,__GEN_EMPTY_ARGS \ ,__GEN_NONEMPTY_ARGS \ )(BOOST_PP_TUPLE_TO_SEQ( parameters )) \ );\ }) #define WRAP_MFN_PR(class_t,method,parameters,return_t) EV(EV(EV(CreateGenericFromMethod_2(class_t,method,EXTRACT_CONST parameters,return_t)))) namespace wrap { template void call_helper(::std::false_type, asIScriptGeneric*g, C*obj, R (C::*fn)(P...), P... args) { new (g->GetAddressOfReturnLocation()) gw::Proxy ((obj->*fn)(args...)); } template void call_helper(::std::true_type,asIScriptGeneric*g, C*obj, R (C::*fn)(P...), P... args) { (obj->*fn)(args...); } template void call_helper(::std::false_type, asIScriptGeneric*g, C*obj, R (C::*fn)(P...)const, P... args) { new (g->GetAddressOfReturnLocation()) gw::Proxy ((obj->*fn)(args...)); } template void call_helper(::std::true_type,asIScriptGeneric*g, C*obj, R (C::*fn)(P...)const, P... args) { (obj->*fn)(args...); } template void call(asIScriptGeneric*g, C*obj, R (C::*fn)(P...), P... args) { call_helper(::std::is_void(), g, obj, fn, args...); } template void callconst(asIScriptGeneric*g, C*obj, R (C::*fn)(P...)const, P... args) { call_helper(std::is_void(), g, obj, fn, args...); } } // namespace wrap #endif // ndef _MSC_VER