a6919ef889
Use `try{}` in `try_fold` to decouple iterators in the library from `Try` details
I'd like to experiment with changing the `?`/`try` desugaring and correspondingly the `Try` trait (see #42327 for discussions about the suboptimalities of the current one) and this change would keep from needing any `cfg(bootstrap)` in iterator things.
This will be lowered to the same thing, so shouldn't cause any perf issues:
08e2d46166/compiler/rustc_ast_lowering/src/expr.rs (L428-L429)
But ~~I'll trigger~~ I've triggered [a perf run](https://perf.rust-lang.org/compare.html?start=d65c08e9cc164b7b44de53503fae859a4fafd976&end=2c067c5235e779cd75e9f0cdfe572c64f1a12b9b) just in case.
~~EDIT: changed to a draft because of the rustfmt-only syntax error. zulip thread about it: https://rust-lang.zulipchat.com/#narrow/stream/122651-general/topic/New.20bootstrap.20rustfmt.20doesn't.20support.20syntax.20from.20sept.3F/near/213098097~~
EDIT: This now includes a rustfmt version bump to get through tidy.