Adding invariant check to every method of a Class

Question

I have a class with many methods and would like to check for pre/post conditions, such as is mMember == null and invoke function x() if not.

Is it possible to add pre/post conditions to every member of that class automatically? The class is defined in class.h and all methods are defined in class.cpp. Being able to define a macro at the start of the class.cpp would be ideal that would be inserted on every function entry in that file only.

I know I can manually add the same precondition/postcondition (using destructors) manually on every function entry but I keep running into this problem time and time again. This is not ideal as I can not check these changes in and must maintain them locally and they bit root from other people's changes.

Answer 1

I have not ever been able to do this in C++; I've always used a set of macros manually added to each member function.

It sounds like a job that might be well-suited to Aspect Oriented Programming, though, and I see that there are libraries out there for AOP in C++, such as AspectC++. It might be worth at least taking a look at one of these and seeing if it can be used to solve your problem.

Answer 2

D programming language supports Design By Contract programming natively. Also is designed to be binary compatible with C/C++ which means code in libraries with those languages can call each other (this is the theory). There is supposedly an AOP weaver for D, but i couldn't find any links