alt Hacker NewsThis is untrue. The MS Office team is using a non-standard MSVC compiler flag that turns standard #include into header units, which treats those header files in a way similar to precompiled header files. This requires no changes to source code, except for some corner cases they mention in that very blog post to work around some compiler quirks.
That is not the same as using modules, which they have not done.
There's nothing non-standard happening there. The compiler is allowed to translate #include -> import. Here's the standardese expressing that: https://eel.is/c%2B%2Bdraft/cpp.include#10.
I do agree, it's not _exactly_ the same as using _named modules_, but header units share an almost identical piece of machinery in the compiler as named modules. This makes the (future planned) transition to named modules a lot easier since we know the underlying machinery works.
The actual blocker for named modules is not MSVC, it's other compilers catching up--which clang and gcc are doing quite quickly!