[Manishearth]

> It's somewhat controversial in the Rust community

We added a lint to clippy that detects places where you could rely on elision but don't. I'm particularly fond of it, because many Rust programmers (including me) still default to the pre-input-output rule regime by explicitly typing out `fn<'a>(&'a u8)-> &'a u8`. It's caught a lot of this and made code nice and clean.

However, we've have multiple people ask the lint to be off-by-default for input-output cases where one of the two sides has a struct/enum lifetime (`Foo<'a>`, not `&'a _`), because it's nice for that to be explicit. (At the same time, multiple people feel like it should stay)

We'll have to see what happens when we RfC the clippy defaults.