70468af591
Suggest `impl Fn*` and `impl Future` in `-> _` return suggestions Follow-up to #106172, only the last commit is relevant. Can rebase once that PR is landed for easier review. Suggests `impl Future` and `impl Fn{,Mut,Once}` in `-> _` return suggestions. r? `@estebank`
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.