Struct RegionConstraintStorage 

pub struct RegionConstraintStorage<'db> {
    pub(super) var_infos: IndexVec<RegionVid, RegionVariableInfo>,
    pub(super) data: RegionConstraintData<'db>,
    lubs: FxHashMap<TwoRegions<'db>, RegionVid>,
    glbs: FxHashMap<TwoRegions<'db>, RegionVid>,
    pub(super) unification_table: UnificationTableStorage<RegionVidKey<'db>>,
    any_unifications: bool,
}

Fields

var_infos: IndexVec<RegionVid, RegionVariableInfo>

For each RegionVid, the corresponding RegionVariableOrigin.

data: RegionConstraintData<'db>

lubs: FxHashMap<TwoRegions<'db>, RegionVid>

For a given pair of regions (R1, R2), maps to a region R3 that is designated as their LUB (edges R1 <= R3 and R2 <= R3 exist). This prevents us from making many such regions.

glbs: FxHashMap<TwoRegions<'db>, RegionVid>

For a given pair of regions (R1, R2), maps to a region R3 that is designated as their GLB (edges R3 <= R1 and R3 <= R2 exist). This prevents us from making many such regions.

unification_table: UnificationTableStorage<RegionVidKey<'db>>

When we add a R1 == R2 constraint, we currently add (a) edges R1 <= R2 and R2 <= R1 and (b) we unify the two regions in this table. You can then call opportunistic_resolve_var early which will map R1 and R2 to some common region (i.e., either R1 or R2). This is important when fulfillment, dropck and other such code is iterating to a fixed point, because otherwise we sometimes would wind up with a fresh stream of region variables that have been equated but appear distinct.

any_unifications: bool

a flag set to true when we perform any unifications; this is used to micro-optimize take_and_reset_data

Implementations

impl<'db> RegionConstraintStorage<'db>

pub(crate) fn with_log<'a>( &'a mut self, undo_log: &'a mut InferCtxtUndoLogs<'db>, ) -> RegionConstraintCollector<'db, 'a>

Trait Implementations

impl<'db> Clone for RegionConstraintStorage<'db>

fn clone(&self) -> RegionConstraintStorage<'db>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'db> Debug for RegionConstraintStorage<'db>

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

Formats the value using the given formatter.

impl<'db> Default for RegionConstraintStorage<'db>

fn default() -> RegionConstraintStorage<'db>

Returns the “default value” for a type.

impl<'db> Rollback<UndoLog<'db>> for RegionConstraintStorage<'db>

fn reverse(&mut self, undo: UndoLog<'db>)