Struct rustc_infer::infer::free_regions::FreeRegionMap

pub struct FreeRegionMap<'tcx> {
    pub(crate) relation: TransitiveRelation<Region<'tcx>>,
}

Fields

relation: TransitiveRelation<Region<'tcx>>

Stores the relation a < b, where a and b are regions.

Invariant: only free regions like 'x or 'static are stored in this relation, not scopes.

Implementations

impl<'tcx> FreeRegionMap<'tcx>

pub fn elements(&self) -> impl Iterator<Item = Region<'tcx>> + '_

pub fn is_empty(&self) -> bool

pub fn sub_free_regions(
    &self,
    tcx: TyCtxt<'tcx>,
    r_a: Region<'tcx>,
    r_b: Region<'tcx>
) -> bool

Tests whether r_a <= r_b.

Both regions must meet is_free_or_static.

Subtle: one tricky case that this code gets correct is as follows. If we know that r_b: 'static, then this function will return true, even though we don’t know anything that directly relates r_a and r_b.

fn check_relation(&self, r_a: Region<'tcx>, r_b: Region<'tcx>) -> bool

Check whether r_a <= r_b is found in the relation.

pub fn lub_free_regions(
    &self,
    tcx: TyCtxt<'tcx>,
    r_a: Region<'tcx>,
    r_b: Region<'tcx>
) -> Region<'tcx>

Computes the least-upper-bound of two free regions. In some cases, this is more conservative than necessary, in order to avoid making arbitrary choices. See TransitiveRelation::postdom_upper_bound for more details.

Trait Implementations

impl<'tcx> Clone for FreeRegionMap<'tcx>

fn clone(&self) -> FreeRegionMap<'tcx>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'tcx> Debug for FreeRegionMap<'tcx>

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

Formats the value using the given formatter.

impl<'a, 'tcx> Lift<'tcx> for FreeRegionMap<'a>

type Lifted = FreeRegionMap<'tcx>

fn lift_to_tcx(self, tcx: TyCtxt<'tcx>) -> Option<FreeRegionMap<'tcx>>

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: 128 bytes