diff options
Diffstat (limited to 'compiler/rustc_middle/src/ty/closure.rs')
| -rw-r--r-- | compiler/rustc_middle/src/ty/closure.rs | 82 |
1 files changed, 39 insertions, 43 deletions
diff --git a/compiler/rustc_middle/src/ty/closure.rs b/compiler/rustc_middle/src/ty/closure.rs index df67bb505a6..b8c7d6cf3b1 100644 --- a/compiler/rustc_middle/src/ty/closure.rs +++ b/compiler/rustc_middle/src/ty/closure.rs @@ -422,53 +422,49 @@ pub fn analyze_coroutine_closure_captures<'a, 'tcx: 'a, T>( child_captures: impl IntoIterator<Item = &'a CapturedPlace<'tcx>>, mut for_each: impl FnMut((usize, &'a CapturedPlace<'tcx>), (usize, &'a CapturedPlace<'tcx>)) -> T, ) -> impl Iterator<Item = T> { - std::iter::from_coroutine( - #[coroutine] - move || { - let mut child_captures = child_captures.into_iter().enumerate().peekable(); - - // One parent capture may correspond to several child captures if we end up - // refining the set of captures via edition-2021 precise captures. We want to - // match up any number of child captures with one parent capture, so we keep - // peeking off this `Peekable` until the child doesn't match anymore. - for (parent_field_idx, parent_capture) in parent_captures.into_iter().enumerate() { - // Make sure we use every field at least once, b/c why are we capturing something - // if it's not used in the inner coroutine. - let mut field_used_at_least_once = false; - - // A parent matches a child if they share the same prefix of projections. - // The child may have more, if it is capturing sub-fields out of - // something that is captured by-move in the parent closure. - while child_captures.peek().is_some_and(|(_, child_capture)| { - child_prefix_matches_parent_projections(parent_capture, child_capture) - }) { - let (child_field_idx, child_capture) = child_captures.next().unwrap(); - // This analysis only makes sense if the parent capture is a - // prefix of the child capture. - assert!( - child_capture.place.projections.len() - >= parent_capture.place.projections.len(), - "parent capture ({parent_capture:#?}) expected to be prefix of \ + gen move { + let mut child_captures = child_captures.into_iter().enumerate().peekable(); + + // One parent capture may correspond to several child captures if we end up + // refining the set of captures via edition-2021 precise captures. We want to + // match up any number of child captures with one parent capture, so we keep + // peeking off this `Peekable` until the child doesn't match anymore. + for (parent_field_idx, parent_capture) in parent_captures.into_iter().enumerate() { + // Make sure we use every field at least once, b/c why are we capturing something + // if it's not used in the inner coroutine. + let mut field_used_at_least_once = false; + + // A parent matches a child if they share the same prefix of projections. + // The child may have more, if it is capturing sub-fields out of + // something that is captured by-move in the parent closure. + while child_captures.peek().is_some_and(|(_, child_capture)| { + child_prefix_matches_parent_projections(parent_capture, child_capture) + }) { + let (child_field_idx, child_capture) = child_captures.next().unwrap(); + // This analysis only makes sense if the parent capture is a + // prefix of the child capture. + assert!( + child_capture.place.projections.len() >= parent_capture.place.projections.len(), + "parent capture ({parent_capture:#?}) expected to be prefix of \ child capture ({child_capture:#?})" - ); - - yield for_each( - (parent_field_idx, parent_capture), - (child_field_idx, child_capture), - ); - - field_used_at_least_once = true; - } + ); - // Make sure the field was used at least once. - assert!( - field_used_at_least_once, - "we captured {parent_capture:#?} but it was not used in the child coroutine?" + yield for_each( + (parent_field_idx, parent_capture), + (child_field_idx, child_capture), ); + + field_used_at_least_once = true; } - assert_eq!(child_captures.next(), None, "leftover child captures?"); - }, - ) + + // Make sure the field was used at least once. + assert!( + field_used_at_least_once, + "we captured {parent_capture:#?} but it was not used in the child coroutine?" + ); + } + assert_eq!(child_captures.next(), None, "leftover child captures?"); + } } fn child_prefix_matches_parent_projections( |
