I’ve personally tabled the idea, in part because it would be a much more disruptive change to existing code. By contrast, the proposal in this thread, while requiring some breakage in the next checkpoint, has a very straightfoward, easily automatable fix.
In addition, there’s the possibility of something like
_foo.rs being an anonymous module (or also the inline modules thread). So we may be able to recover that idea in a less disruptive, more orthogonal way.
At the moment, my personal focus is to try to find a relatively conservative option that (1) solves some of the more prominent issues in the module system and (2) lays a good foundation for future work like anonymous modules.