Forwarding all unknown methods calls and properties usage to special functions in C++

  attributes, c++, methods, properties, reflection

In C++ if I have object of some class Class obj; I want to be able to intercept and process calls of methods of any names and arguments like obj.add(123), also to process any properties usage like auto x = obj.value;.

The thing is that I don’t know what method or property names will be used, e.g. one may use obj.abc(1, 2, true) or auto x = obj.xyz;.

So if somebody called obj.abc(1, 2, true) I want next method to be called with args ("abc", 1, 2, true):

template <typename ... Args>
std::any ProcessMethod(std::string const & method_name, Args && ... args) {/*...*/}

or if property was used auto x = obj.xyz; I want next method to be called with ("xyz") argument:

std::any ProcessProperty(std::string const & property_name) {/*...*/}

Those two methods above use runtime approach. Even better would be for me to pass called method or property name at compile time (as compile time fixed string). So that I can find out method return type or property type at compile time, i.e. do (for some special class FixedString holding string at compile time):

template <FixedString method_name, typename ... Args>
typename ReturnTypeOf<method_name>::type ProcessMethod(Args && ... args) {/*...*/}

template <FixedString property_name>
typename PropertyTypeOf<property_name>::type & ProcessProperty() {/*...*/}

Is that possible anyhow to intercept all calls to unknown methods or properties and forward them to last two methods above?

Of cause I can use next syntax: obj.call<"abc">(1, 2, true) and auto x = obj.prop<"xyz">(); to solve my task, but if it is possible to solve anyhow in C++ I would like to stay with syntax obj.abc(1, 2, true) and auto x = obj.xyz;.

Is very last syntax above achievable anyhow through C++ reflection or templates magic?

Source: Windows Questions C++

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