[ziotom78]

If I understand well, Ada packages provide the necessary architecture for this kind of stuff. A package is like a Python "module", but it is typically split in two files: a specification, just containing the declaration of all the types and functions exported by the package, and a body, which actually implements the functions working on those types. When writing a program which uses that package, if you only compile it without linking, the compiler will complain about wrong types even if no function has been implemented yet.

A poor man's version of the above schema can be achieved in C/C++ as well. Just declare your functions in a header file and include it in your program, then compile without linking.

[willtim]

This is not the same thing as deferred type errors though. The programs are still type correct, it's just that some of the implementations are missing / producing errors.