Including an exception class in a header file

Question

I have a pair of files, say Foo.cpp and Foo.hpp that define a class, say Foo. Foo's methods have the potential to throw an exception, defined in the file MyException.hpp, but Foo.hpp does not need MyException.

Obviously the .cpp needs to include the exception header, but should I include the exception header in Foo.hpp instead to allow any files that use Foo to have a definition of the exception?

Answer 1

The usual rule of thumb is that every file should include the headers that it needs. So, no, don't add MyException.hpp to Foo.hpp unless it's needed there. Code that deals with your exception class should #include "MyException.hpp". So, obviously, whichever files implement the member functions that throw this exception need to include "MyException.hpp", and any files that include code that catch this exception also need it.