Embind references test

embindreferences.cpp

#include <emscripten/bind.h>

#include <functional>

class ByRef {
	int field=0;
public:
  	ByRef& getRef() {return *this;}
	ByRef* getPtr() {return this;}
	const ByRef& getConstRef() const {return *this;}
	int getValue() const {return field;}
	void incr() {field++;}
};

void incrRef(ByRef &r) {r.incr();}
void incrPointer(ByRef *p) {p->incr();}
ByRef& passthrough(ByRef& r) {return r;}
ByRef copy(ByRef& r) {return r;}

int getValueByConstRef(const ByRef& r) {return r.getValue();}
int getValueByRef(ByRef& r) {return r.getValue();}
int getValueByPointer(ByRef* r) {return r->getValue();}

template <typename T, T> struct proxy;

template <typename T, typename R, typename ...Args, R (T::*mf)(Args...)>
struct proxy<R (T::*)(Args...), mf>
{
	using ptr = typename std::add_pointer<typename std::remove_reference<R>::type>::type;
    static ptr call(T & obj, Args &&... args)
    {
        return &((obj.*mf)(std::forward<Args>(args)...));
    }
};

#define RETURN_POINTER(value) &proxy<decltype(value), (value)>::call

EMSCRIPTEN_BINDINGS(valueMethod) {
	using namespace emscripten;

	function("incrRef", &incrRef, references_as_pointers());
	function("incrPointer", &incrPointer, allow_raw_pointers());
	function("pass", &passthrough, references_as_pointers());
	function("copy", &copy);
	function("getValueByRef", &getValueByRef);
	function("getValueByPointer", &getValueByPointer, allow_raw_pointers());
	function("getValueByConstRef", &getValueByConstRef);

	class_<ByRef>("Ref").constructor()
	  .function("ref",&ByRef::getRef, references_as_pointers())
	  .function("ptr",RETURN_POINTER(&ByRef::getRef), allow_raw_pointers())
	  .function("getPtr", &ByRef::getPtr, allow_raw_pointers())
	  .function("constRef", &ByRef::getConstRef)
	  .function("value",&ByRef::getValue)
	  .function("incr",&ByRef::incr)
	  ;
}