Idea: Fallible iterator mapping with `try_map`

[Luro02]

A while ago I had a similar idea, which may be relevant? Never got to actually submit the RFC, because I did not have the time for it

[pre-RFC] TryFromIterator and try_collect to enable collecting to arrays

I was experimenting with const generics and found out that it is not possible to collect an iterator into an array, which is very annoying, when you are working in a no-std environment. This is my first time writing a (pre-)RFC, so any feedback is greatly appreciated (especially spelling and grammar errors) Feature Name: try_from_iterator Start Date: 2021-04-04 RFC PR: rust-lang/rfcs#0000 Rust Issue: rust-lang/rust#0000 Summary The standard library provides the FromI…