Struct ConstraintGraph

pub(crate) struct ConstraintGraph<D: ConstraintGraphDirection> {
    _direction: D,
    first_constraints: IndexVec<RegionVid, Option<OutlivesConstraintIndex>>,
    next_constraints: IndexVec<OutlivesConstraintIndex, Option<OutlivesConstraintIndex>>,
}

The construct graph organizes the constraints by their end-points. It can be used to view a R1: R2 constraint as either an edge R1 -> R2 or R2 -> R1 depending on the direction type D.

Fields

_direction: D

first_constraints: IndexVec<RegionVid, Option<OutlivesConstraintIndex>>

next_constraints: IndexVec<OutlivesConstraintIndex, Option<OutlivesConstraintIndex>>

Implementations

impl<D: ConstraintGraphDirection> ConstraintGraph<D>

pub(crate) fn new( direction: D, set: &OutlivesConstraintSet<'_>, num_region_vars: usize, ) -> Self

Creates a “dependency graph” where each region constraint R1: R2 is treated as an edge R1 -> R2. We use this graph to construct SCCs for region inference but also for error reporting.

pub(crate) fn region_graph<'a, 'tcx>( &'a self, set: &'a OutlivesConstraintSet<'tcx>, static_region: RegionVid, ) -> RegionGraph<'a, 'tcx, D>

Given the constraint set from which this graph was built creates a region graph so that you can iterate over regions and not constraints.

pub(crate) fn outgoing_edges<'a, 'tcx>( &'a self, region_sup: RegionVid, constraints: &'a OutlivesConstraintSet<'tcx>, static_region: RegionVid, ) -> Edges<'a, 'tcx, D>

Given a region R, iterate over all constraints R: R1.

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.