Struct rustc_infer::infer::free_regions::FreeRegionMap

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

Fields

relation: TransitiveRelation<Region<'tcx>>

Implementations

impl<'tcx> FreeRegionMap<'tcx>

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

pub fn is_empty(&self) -> bool

pub fn relate_regions(&mut self, sub: Region<'tcx>, sup: Region<'tcx>)

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.

Also available through the FreeRegionRelations trait below.

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 is_free(&self, r: Region<'_>) -> bool

True for free regions other than 'static.

pub fn is_free_or_static(&self, r: Region<'_>) -> bool

True if r is a free region or static of the sort that this free region map can be used with.

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<'tcx> Default for FreeRegionMap<'tcx>

fn default() -> FreeRegionMap<'tcx>

Returns the “default value” for a type.

impl<'tcx> FreeRegionRelations<'tcx> for FreeRegionMap<'tcx>

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

Tests whether r_a <= r_b. Both must be free regions or 'static.

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

type Lifted = FreeRegionMap<'tcx>

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