A comment from the author /u/ClayTownR on reddit:

The original reason I got into garbage collectors (a long time ago, and long forgotten now) was that I was implementing a runtime for a scripted language. When I originally wrote it, I had to do some manual finagling with weak references to ensure that I didn't leak any memory.

In general, the main uses for a GC in rust would be interpreters for other GC languages and working with graphs.

I just published futures-concurrency v7.4.1 which adds support for lending iteration on the newly added Group types!

https://github.com/yoshuawuyts/futures-concurrency/releases/tag/v7.4.1

This should replace the final remaining use there was for select!, meaning we now have structured alternatives for all kinds of concurrency operations you could possibly want to express.

I have a written a bit of rust by now, but one problem I always seem to encounter it that the features a create supports never seem to be documented. Neither what features are available, what they each do or which are default. Is that really the case, or am I missing something?

I constantly seem to include something from the docs, only to be told by the compiler that it does not exist, and then I have to open the source for the create to figure out if it's hidden behind a feature flag.

Also, is it really true that I can't disable a single feature from the default set, without having to copy the default list and manually removing it?

There are only a few SAT solvers for Rust and this one looks well documented and will be well supported because it is part of Conda.

When returning an immutable reference to a private struct field. (On mobile and used vertical bars instead of a bunch of HTML codes)

I started off avoiding mod.rs because it's the old way and I prefer having the module name as the filename. However, if the module needs a folder for submodules anyway, then there's a reason to tuck it away as mod.rs, especially if not doing so leaves lots of duplicate names (a.rs, b.rs, c.rs, ..., a/, b/, c/).

But then I don't really like to have much else in mod.rs other than mod declarations and pub use. Maybe a utility fn or a not-unwieldly implementation of struct "Foo", the module's namesake.