Question

Fact: Forward declarations (of class-types) are to be preferred over includes.

Is there a downside to forward-declaring everything in a header and including that header? (I’m guessing the compilation time shouldn’t increase by a lot)

In large codebases, forward-declarations can take up to a lot of screen-space, and it would be cool to replace them with a single include – however, it doesn’t make sense to have a forward-declaration header for each header with forward declarations.

Has anyone done this or seen this before?

Answer 1

I usually do so in my projects. But I split forward declarations in modules. For example: gui, core and so on. That gives a good balance between recompiling a lot because of using includes in headers and between writing forward declarations manually