macros.cpp

#include <cstring>
#include <iostream>

class Base
{
	struct SetParamHelper
	{
		Base* obj;

		SetParamHelper(Base* obj): obj(obj) {}

		const SetParamHelper& operator() (const char* name, int value) const
		{
			obj->setParam(name, value);
			return *this;
		}
	};

public:
	SetParamHelper setParams(const char* name, int value)
	{
		setParam(name, value);
		return SetParamHelper(this);
	}

	virtual void setParam(const char* name, int value)
	{
		//
	}

	virtual int  getParam(const char* name)
	{
		return -1;
	}
};

#define SET_PARAM_FIRST(param) \
	if(strcmp(name, #param) == 0) param = value;

#define SET_PARAM_NEXT(param) \
	else if(strcmp(name, #param) == 0) param = value;

#define IMPLEMENT_SET_PARAM(PARAM_MAP) \
	virtual void setParam(const char* name, int value) { PARAM_MAP(SET_PARAM_FIRST, SET_PARAM_NEXT); }

#define GET_PARAM_FIRST(param) \
	if(strcmp(name, #param) == 0) return param;

#define GET_PARAM_NEXT(param) \
	else if(strcmp(name, #param) == 0) return param;

#define IMPLEMENT_GET_PARAM(PARAM_MAP) \
	virtual int getParam(const char* name, int value) { PARAM_MAP(GET_PARAM_FIRST, GET_PARAM_NEXT) else return -1; }

#define IMPLEMENT_GET_SET(PARAM_MAP) \
	IMPLEMENT_SET_PARAM(PARAM_MAP) \
	IMPLEMENT_GET_PARAM(PARAM_MAP)

#define DECLARE_PARAM(name) \
	int name;

#define IMPLEMENT_PARAMS(PARAM_MAP) \
	IMPLEMENT_GET_SET(PARAM_MAP) \
	PARAM_MAP(DECLARE_PARAM, DECLARE_PARAM)

class Foo : public Base
{
public:
#define FOO_PARAMS(FIRST, NEXT) \
	FIRST(intelligence) \
	NEXT(wisdom) \
	NEXT(charisma)

	IMPLEMENT_PARAMS(FOO_PARAMS)
};

int main()
{
	Foo f;
	f.setParams
		("wisdom", 10)
		("intelligence", 25)
		("charisma", 55);

	std::cout << f.charisma;
}