Tricky programs

In most questions here I’d like to answer “The program does not compile”, but that’s usually the wrong answer:

Do you know how many of those examples could not compile in the successive Rust edition?

Impossible to tell because predicting things, especially the furure is hard. But i suspect none most of them will not change as the mostly relate to core ideas in Rust.

didn’t know #5 was a bug

Previous discussion: Rust puzzlers in quiz form

Also, @cramertj commented on /r/rust:

FWIW #5 is a bug that I believe the plan-of-record is to fix as part of the universes work that Niko has been doing.