First read cmake-cxxmodules(7)
Than we have to know and decide which variant of Standard C++ Modules we want:
Daniela's choice for the fmt library was export-extern-c-style
This seems to be useful for existing header-only libraries like asio, fmt, and i.e. beman.scope.
But note the performance tips and other recommendations:
- The ABI of your library
- Less duplicated generated code
- Providing a header to skip parsing redundant headers
Also note how we may want to Importing modules in other Beman libraries
and last but not least Including headers after import is not well-supported