Dear SG15,

     I wanted to move away from the talk of package managers and other such
things for a bit, to talk about something closer to the build system.
Dependency management is becoming a bit of a hot topic now that modules
have been pushed to Core for wording review. std::embed (p1040
<https://thephd.github.io/vendor/future_cxx/papers/d1040.html>) is facing
significant uphill challenges because it requires full Semantic Analysis to
communicate dependency information, which is a no-go for preprocessor
scanners and things like /showIncludes or -MMD.

     To address the problem of dependency tracking for a source file, I
wanted to add a module directive called module-requires, p1130
<https://thephd.github.io/vendor/future_cxx/papers/d1130.html>.

     This paper is supposed to allow folks the ability to say "some
resource out there should trigger a re-compile of this file / module if it
ever changes". If we get module:private;, we could tag it to the module's
implementation only as well.

Any thoughts?

Sincerely,
JeanHeyd Meneide