Vetting the cargo

Vetting the cargo

Your conclusion doesn't follow from your argument.

The standard library cannot change in a backwards-incompatible fashion; this is simply not permitted under any circumstances. You can add it it, and you can fix bugs, but you can't break existing users. Further, as you update your language environment, you will get newer implementations of the standard library; one of the defining special cases about the standard library is that the compiler is allowed to assume that the standard library is present (which is why Rust currently has three standard libraries - core, which is things the compiler cannot function without, alloc, which is all of core, plus the things that the compiler needs when the heap is available, and std, which is the full-fat standard library when running in userspace on a normal OS).

This means we cannot remove anything from the standard library, ever. No matter how big a mistake it is, it has to remain present in the standard library forever, acting as a foot-gun for new users (see gets in C, for example), because removing it will break backwards compatibility. And because Rust documents all of its standard library, that means that it's visible to new users whether we want them to use it or not.

It's worth noting, too, that just because it's in an external crate doesn't mean it stops working; you can still use error-chain or failure, and the backwards compatibility commitment of the compiler and standard library means that they will still work into the future. They're just not being improved over time, and the ecosystem as a whole is no longer using them in new projects.

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