Struct rustc_mir::borrow_check::nll::universal_regions::UniversalRegionIndices

struct UniversalRegionIndices<'tcx> {
    indices: FxHashMap<Region<'tcx>, RegionVid>,
}

🔬 This is a nightly-only experimental API. (rustc_private)

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Fields

indices: FxHashMap<Region<'tcx>, RegionVid>

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

For those regions that may appear in the parameter environment ('static and early-bound regions), we maintain a map from the ty::Region to the internal RegionVid we are using. This is used because trait matching and type-checking will feed us region constraints that reference those regions and we need to be able to map them our internal RegionVid. This is basically equivalent to a Substs, except that it also contains an entry for ReStatic -- it might be nice to just use a substs, and then handle ReStatic another way.

Methods

impl<'tcx> UniversalRegionIndices<'tcx>

fn insert_late_bound_region(&mut self, r: Region<'tcx>, vid: RegionVid)

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

Initially, the UniversalRegionIndices map contains only the early-bound regions in scope. Once that is all setup, we come in later and instantiate the late-bound regions, and then we insert the ReFree version of those into the map as well. These are used for error reporting.

pub fn to_region_vid(&self, r: Region<'tcx>) -> RegionVid

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

Converts r into a local inference variable: r can either by a ReVar (i.e., already a reference to an inference variable) or it can be 'static or some early-bound region. This is useful when taking the results from type-checking and trait-matching, which may sometimes reference those regions from the ParamEnv. It is also used during initialization. Relies on the indices map having been fully initialized.

pub fn fold_to_region_vids<T>(&self, tcx: TyCtxt<'_, '_, 'tcx>, value: &T) -> T where     T: TypeFoldable<'tcx>,

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?

Replace all free regions in value with region vids, as returned by to_region_vid.

Trait Implementations

impl<'tcx> Debug for UniversalRegionIndices<'tcx>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.