As promised, I have published a Python script at

 https://github.com/josuttis/cppmodules

The script circumvents the current restrictions of Visual C++ for simple C++ example that want to test modules. I hope this contribution will help to bring modules faster to life.

You can find the script with documentation and test code at the web site. However let me mention a few basic aspects here.

Unlike Visual C++, the script

• allows programmers to use arbitrary file suffixes for module units AND
• does not require to specify options such as /internalPartition or /interface AND
  
• enables programmers to pass ALL units of a C++ program using modules on ONE command line

• modall_if.cppm : The module interface unit
• modall_ifpart.cppm : An interface partition unit
• modall_part.cppm : An internal partition
• modall_impl.cpp : An implementation unit

and to test this we have:

• modall_test.cpp : A traditional translation unit

Calling:

 clmod.py /std:c++latest modall_part.cppm modall_ifpart.cppm modall_if.cppm modall_impl.cpp modall_test.cpp /Femodall.exe

will automatically do the right thing:

 cl /std:c++latest /Femodall.exe /TP /c /internalPartition modall_part.cppm
 cl /std:c++latest /Femodall.exe /TP /c /interface modall_ifpart.cppm
 cl /std:c++latest /Femodall.exe /TP /c /interface modall_if.cppm
 cl /std:c++latest /Femodall.exe /TP /c modall_impl.cpp
 cl /std:c++latest /Femodall.exe /TP /c modall_test.cpp
 cl /std:c++latest /Femodall.exe modall_part.obj modall_ifpart.obj modall_if.obj modall_impl.obj modall_test.obj

Note that the order of the files still matters.

This example also works when using the Visual C++ conventions:

• .ixx for interface units (all other with .cpp or so)
• .cpp for all units (all gcc supports)

Thus, this script does not propose any file suffixes as a convention.

Instead, you now can use any convention to be able to have a first portable C++ program using modules just passing all files to the compiler.

The script is not perfect. One drawback is that it requires compilation by command line. The script is still a workaround until Visual C++ provides this support directly (which should be easy to do). But at least you can now make easy experience with portable module examples not using an IDE.

Hope this helps.

Feedback welcome (please cc me directly as I have not subscribed the SG155 reflector).

  Nico

-- 
--- 
Nicolai M. Josuttis
www.josuttis.de
+49 (0)531 / 129 88 86
+49 (0)700 / JOSUTTIS

Books:
 C++: http://cppstd20.com, http://cppstd17.com, http://cppmove.com,
      http://cppstdlib.com, http://tmplbook.com