bors 208dd2032b Auto merge of #118847 - eholk:for-await, r=compiler-errors ... Add support for `for await` loops This adds support for `for await` loops. This includes parsing, desugaring in AST->HIR lowering, and adding some support functions to the library. Given a loop like: ```rust for await i in iter { ... } ``` this is desugared to something like: ```rust let mut iter = iter.into_async_iter(); while let Some(i) = loop { match core::pin::Pin::new(&mut iter).poll_next(cx) { Poll::Ready(i) => break i, Poll::Pending => yield, } } { ... } ``` This PR also adds a basic `IntoAsyncIterator` trait. This is partly for symmetry with the way `Iterator` and `IntoIterator` work. The other reason is that for async iterators it's helpful to have a place apart from the data structure being iterated over to store state. `IntoAsyncIterator` gives us a good place to do this. I've gated this feature behind `async_for_loop` and opened #118898 as the feature tracking issue. r? `@compiler-errors`		2023-12-22 14:17:10 +00:00
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src	Auto merge of #118847 - eholk:for-await, r=compiler-errors	2023-12-22 14:17:10 +00:00
Cargo.toml	Update itertools to 0.11.	2023-11-22 08:13:21 +11:00
messages.ftl	Auto merge of #119163 - fmease:refactor-ast-trait-bound-modifiers, r=compiler-errors	2023-12-22 02:00:55 +00:00