In D, you can just do a static foreach over a sequence to generate case labels:
That is template for as part of the C++26 reflection work.
https://isocpp.org/files/papers/P2996R4.html
You will also find some well known names here,
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p34...
Otherwise I rather stay in JVM/CLR/V8 land, when I don't need to.
I have been around D since Andrei Alexandrescu's book was published, even he is now back in C++ at NVidia, as his main work after he kind of stepped away from his role in D development.
And he is one of the figures on C++26 reflection papers.
Many people forget C++ is a C sibling, born at AT&T on the same building UNIX and C were being handled, thus it was quite an easy win for C compiler vendors, to add C++ support to their toolchains.
Note that Objective-C also never made it outside NeXT, GNUStep was never that good clone, and had it not been for Apple's acquision and success, maybe we would no longer speak about it.
When Facebook or Remedy Games played with D, we hoped it would somehow improve adoption, that was never the case, and both companies no longer use D.