Struct MirTypeckRegionConstraints

pub(crate) struct MirTypeckRegionConstraints<'tcx> {
    pub(crate) placeholder_indices: PlaceholderIndices,
    pub(crate) placeholder_index_to_region: IndexVec<PlaceholderIndex, Region<'tcx>>,
    pub(crate) liveness_constraints: LivenessValues,
    pub(crate) outlives_constraints: OutlivesConstraintSet<'tcx>,
    pub(crate) member_constraints: MemberConstraintSet<'tcx, RegionVid>,
    pub(crate) universe_causes: FxIndexMap<UniverseIndex, UniverseInfo<'tcx>>,
    pub(crate) type_tests: Vec<TypeTest<'tcx>>,
}

A collection of region constraints that must be satisfied for the program to be considered well-typed.

Fields

placeholder_indices: PlaceholderIndices

Maps from a ty::Placeholder to the corresponding PlaceholderIndex bit that we will use for it.

To keep everything in sync, do not insert this set directly. Instead, use the placeholder_region helper.

placeholder_index_to_region: IndexVec<PlaceholderIndex, Region<'tcx>>

Each time we add a placeholder to placeholder_indices, we also create a corresponding “representative” region vid for that wraps it. This vector tracks those. This way, when we convert the same ty::RePlaceholder(p) twice, we can map to the same underlying RegionVid.

liveness_constraints: LivenessValues

In general, the type-checker is not responsible for enforcing liveness constraints; this job falls to the region inferencer, which performs a liveness analysis. However, in some limited cases, the MIR type-checker creates temporary regions that do not otherwise appear in the MIR – in particular, the late-bound regions that it instantiates at call-sites – and hence it must report on their liveness constraints.

outlives_constraints: OutlivesConstraintSet<'tcx>

member_constraints: MemberConstraintSet<'tcx, RegionVid>

universe_causes: FxIndexMap<UniverseIndex, UniverseInfo<'tcx>>

type_tests: Vec<TypeTest<'tcx>>

Implementations

impl<'tcx> MirTypeckRegionConstraints<'tcx>

fn placeholder_region( &mut self, infcx: &InferCtxt<'tcx>, placeholder: PlaceholderRegion, ) -> Region<'tcx>

Creates a Region for a given PlaceholderRegion, or returns the region that corresponds to a previously created one.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 424 bytes