/// the [rustc guide].
///
/// [rustc guide]: https://rust-lang-nursery.github.io/rustc-guide/traits/hrtb.html
- pub fn replace_late_bound_regions_with_placeholders<T>(&self,
- binder: &ty::Binder<T>)
- -> (T, PlaceholderMap<'tcx>)
- where T : TypeFoldable<'tcx>
+ pub fn replace_late_bound_regions_with_placeholders<T>(
+ &self,
+ binder: &ty::Binder<T>,
+ ) -> (T, PlaceholderMap<'tcx>)
+ where
+ T : TypeFoldable<'tcx>,
{
let new_universe = self.create_subuniverse();
let (result, map) = self.tcx.replace_late_bound_regions(binder, |br| {
- self.tcx.mk_region(ty::RePlaceholder(new_universe, br))
+ self.tcx.mk_region(ty::RePlaceholder(ty::Placeholder {
+ universe: new_universe,
+ name: br,
+ }))
});
debug!("skolemize_bound_regions(binder={:?}, result={:?}, map={:?})",
assert!(
match *r {
ty::ReVar(_) => true,
- ty::RePlaceholder(_, ref br1) => br == br1,
+ ty::RePlaceholder(index) => index.name == *br,
_ => false,
},
"leak-check would have us replace {:?} with {:?}",
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub enum NLLRegionVariableOrigin {
- // During NLL region processing, we create variables for free
- // regions that we encounter in the function signature and
- // elsewhere. This origin indices we've got one of those.
+ /// During NLL region processing, we create variables for free
+ /// regions that we encounter in the function signature and
+ /// elsewhere. This origin indices we've got one of those.
FreeRegion,
- BoundRegion(ty::UniverseIndex),
+ /// "Universal" instantiation of a higher-ranked region (e.g.,
+ /// from a `for<'a> T` binder). Meant to represent "any region".
+ Placeholder(ty::Placeholder),
Existential,
}
pub fn is_universal(self) -> bool {
match self {
NLLRegionVariableOrigin::FreeRegion => true,
- NLLRegionVariableOrigin::BoundRegion(..) => true,
+ NLLRegionVariableOrigin::Placeholder(..) => true,
NLLRegionVariableOrigin::Existential => false,
}
}
| ty::ReErased
| ty::ReFree(..)
| ty::ReEarlyBound(..) => ty::UniverseIndex::ROOT,
- ty::RePlaceholder(universe, _) => universe,
+ ty::RePlaceholder(placeholder) => placeholder.universe,
ty::ReClosureBound(vid) | ty::ReVar(vid) => self.var_universe(vid),
ty::ReLateBound(..) => bug!("universe(): encountered bound region {:?}", region),
ty::ReCanonical(..) => bug!(
obligation.predicate.def_id(),
obligation.predicate.skip_binder().trait_ref.self_ty(),
|impl_def_id| {
- self.probe(|this, snapshot| /* [1] */
- if let Ok(placeholder_map) = this.match_impl(impl_def_id, obligation, snapshot) {
+ self.probe(|this, snapshot| {
+ if let Ok(placeholder_map) = this.match_impl(impl_def_id, obligation, snapshot)
+ {
candidates.vec.push(ImplCandidate(impl_def_id));
// NB: we can safely drop the placeholder map
- // since we are in a probe [1]
+ // since we are in a probe.
mem::drop(placeholder_map);
}
- );
+ });
},
);
}
}
+/// The "placeholder index" fully defines a placeholder region.
+/// Placeholder regions are identified by both a **universe** as well
+/// as a "bound-region" within that universe. The `bound_region` is
+/// basically a name -- distinct bound regions within the same
+/// universe are just two regions with an unknown relationship to one
+/// another.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, PartialOrd, Ord)]
+pub struct Placeholder {
+ pub universe: UniverseIndex,
+ pub name: BoundRegion,
+}
+
/// When type checking, we use the `ParamEnv` to track
/// details about the set of where-clauses that are in scope at this
/// particular point.
/// A placeholder region - basically the higher-ranked version of ReFree.
/// Should not exist after typeck.
- RePlaceholder(ty::UniverseIndex, BoundRegion),
+ RePlaceholder(ty::Placeholder),
/// Empty lifetime is for data that is never accessed.
/// Bottom in the region lattice. We treat ReEmpty somewhat
RegionKind::ReScope(..) => false,
RegionKind::ReStatic => true,
RegionKind::ReVar(..) => false,
- RegionKind::RePlaceholder(_, br) => br.is_named(),
+ RegionKind::RePlaceholder(placeholder) => placeholder.name.is_named(),
RegionKind::ReEmpty => false,
RegionKind::ReErased => false,
RegionKind::ReClosureBound(..) => false,
}
ty::ReLateBound(_, br) |
ty::ReFree(ty::FreeRegion { bound_region: br, .. }) |
- ty::RePlaceholder(_, br) => {
+ ty::RePlaceholder(ty::Placeholder { name: br, .. }) => {
write!(f, "{}", br)
}
ty::ReScope(scope) if cx.identify_regions => {
write!(f, "'?{}", c.index())
}
- ty::RePlaceholder(universe, ref bound_region) => {
- write!(f, "RePlaceholder({:?}, {:?})", universe, bound_region)
+ ty::RePlaceholder(placeholder) => {
+ write!(f, "RePlaceholder({:?})", placeholder)
}
ty::ReEmpty => write!(f, "ReEmpty"),
// lifetimes without names with the value `'0`.
match ty.sty {
ty::TyKind::Ref(ty::RegionKind::ReLateBound(_, br), _, _)
- | ty::TyKind::Ref(ty::RegionKind::RePlaceholder(_, br), _, _) => {
- with_highlight_region_for_bound_region(*br, counter, || format!("{}", ty))
- }
+ | ty::TyKind::Ref(
+ ty::RegionKind::RePlaceholder(ty::Placeholder { name: br, .. }),
+ _,
+ _,
+ ) => with_highlight_region_for_bound_region(*br, counter, || format!("{}", ty)),
_ => format!("{}", ty),
}
}
fn get_region_name_for_ty(&self, ty: ty::Ty<'tcx>, counter: usize) -> String {
match ty.sty {
ty::TyKind::Ref(region, _, _) => match region {
- ty::RegionKind::ReLateBound(_, br) | ty::RegionKind::RePlaceholder(_, br) => {
+ ty::RegionKind::ReLateBound(_, br)
+ | ty::RegionKind::RePlaceholder(ty::Placeholder { name: br, .. }) => {
with_highlight_region_for_bound_region(*br, counter, || format!("{}", region))
}
_ => format!("{}", region),
use super::universal_regions::UniversalRegions;
use borrow_check::nll::constraints::graph::NormalConstraintGraph;
use borrow_check::nll::constraints::{ConstraintSccIndex, ConstraintSet, OutlivesConstraint};
-use borrow_check::nll::region_infer::values::{RegionElement, ToElementIndex};
+use borrow_check::nll::region_infer::values::{PlaceholderIndices, RegionElement, ToElementIndex};
use borrow_check::nll::type_check::free_region_relations::UniversalRegionRelations;
use borrow_check::nll::type_check::Locations;
use rustc::hir::def_id::DefId;
.collect();
// Compute the max universe used anywhere amongst the regions.
- let max_universe = definitions
+ let placeholder_indices: PlaceholderIndices = definitions
.iter()
- .map(|d| d.universe)
- .max()
- .unwrap_or(ty::UniverseIndex::ROOT);
+ .filter_map(|d| match d.origin {
+ NLLRegionVariableOrigin::Placeholder(placeholder) => Some(placeholder),
+ _ => None,
+ })
+ .collect();
let constraints = Rc::new(outlives_constraints); // freeze constraints
let constraint_graph = Rc::new(constraints.graph(definitions.len()));
let fr_static = universal_regions.fr_static;
let constraint_sccs = Rc::new(constraints.compute_sccs(&constraint_graph, fr_static));
- let mut scc_values = RegionValues::new(elements, universal_regions.len(), max_universe);
+ let mut scc_values =
+ RegionValues::new(elements, universal_regions.len(), placeholder_indices);
for region in liveness_constraints.rows() {
let scc = constraint_sccs.scc(region);
self.scc_values.add_element(scc, variable);
}
- NLLRegionVariableOrigin::BoundRegion(ui) => {
- // Each placeholder region X outlives its
- // associated universe but nothing else. Every
- // placeholder region is always in a universe that
- // contains `ui` -- but when placeholder regions
- // are placed into an SCC, that SCC may include
- // things from other universes that do not include
- // `ui`.
+ NLLRegionVariableOrigin::Placeholder(placeholder) => {
+ // Each placeholder region is only visible from
+ // its universe `ui` and its superuniverses. So we
+ // can't just add it into `scc` unless the
+ // universe of the scc can name this region.
let scc_universe = self.scc_universes[scc];
- if ui.is_subset_of(scc_universe) {
- self.scc_values.add_element(scc, ui);
+ if placeholder.universe.is_subset_of(scc_universe) {
+ self.scc_values.add_element(scc, placeholder);
} else {
self.add_incompatible_universe(scc);
}
// B's value, and check whether all of them are nameable
// from universe_a
self.scc_values
- .subuniverses_contained_in(scc_b)
- .all(|u| u.is_subset_of(universe_a))
+ .placeholders_contained_in(scc_b)
+ .all(|p| p.universe.is_subset_of(universe_a))
}
/// Extend `scc` so that it can outlive some placeholder region
);
}
- NLLRegionVariableOrigin::BoundRegion(universe) => {
- self.check_bound_universal_region(infcx, mir, mir_def_id, fr, universe);
+ NLLRegionVariableOrigin::Placeholder(placeholder) => {
+ self.check_bound_universal_region(infcx, mir, mir_def_id, fr, placeholder);
}
NLLRegionVariableOrigin::Existential => {
assert!(self.scc_universes[longer_fr_scc] == ty::UniverseIndex::ROOT);
debug_assert!(
self.scc_values
- .subuniverses_contained_in(longer_fr_scc)
+ .placeholders_contained_in(longer_fr_scc)
.next()
.is_none()
);
mir: &Mir<'tcx>,
_mir_def_id: DefId,
longer_fr: RegionVid,
- universe: ty::UniverseIndex,
+ placeholder: ty::Placeholder,
) {
- debug!("check_bound_universal_region(fr={:?})", longer_fr);
+ debug!(
+ "check_bound_universal_region(fr={:?}, placeholder={:?})",
+ longer_fr, placeholder,
+ );
let longer_fr_scc = self.constraint_sccs.scc(longer_fr);
.find(|element| match element {
RegionElement::Location(_) => true,
RegionElement::RootUniversalRegion(_) => true,
- RegionElement::SubUniversalRegion(ui) => *ui != universe,
+ RegionElement::PlaceholderRegion(placeholder1) => placeholder != *placeholder1,
})
} {
Some(v) => v,
let error_region = match error_element {
RegionElement::Location(l) => self.find_sub_region_live_at(longer_fr, l),
RegionElement::RootUniversalRegion(r) => r,
- RegionElement::SubUniversalRegion(error_ui) => self.definitions
+ RegionElement::PlaceholderRegion(error_placeholder) => self.definitions
.iter_enumerated()
.filter_map(|(r, definition)| match definition.origin {
- NLLRegionVariableOrigin::BoundRegion(ui) if error_ui == ui => Some(r),
+ NLLRegionVariableOrigin::Placeholder(p) if p == error_placeholder => Some(r),
_ => None,
})
.next()
use rustc::mir::{BasicBlock, Location, Mir};
use rustc::ty::{self, RegionVid};
use rustc_data_structures::bit_set::{HybridBitSet, SparseBitMatrix};
+use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::indexed_vec::Idx;
use rustc_data_structures::indexed_vec::IndexVec;
use std::fmt::Debug;
impl RegionValueElements {
crate fn new(mir: &Mir<'_>) -> Self {
let mut num_points = 0;
- let statements_before_block: IndexVec<BasicBlock, usize> = mir
- .basic_blocks()
+ let statements_before_block: IndexVec<BasicBlock, usize> = mir.basic_blocks()
.iter()
.map(|block_data| {
let v = num_points;
let mut basic_blocks = IndexVec::with_capacity(num_points);
for (bb, bb_data) in mir.basic_blocks().iter_enumerated() {
- basic_blocks.extend((0 .. bb_data.statements.len() + 1).map(|_| bb));
+ basic_blocks.extend((0..bb_data.statements.len() + 1).map(|_| bb));
}
Self {
let block = self.basic_blocks[index];
let start_index = self.statements_before_block[block];
let statement_index = index.index() - start_index;
- Location { block, statement_index }
+ Location {
+ block,
+ statement_index,
+ }
}
/// Sometimes we get point-indices back from bitsets that may be
index: PointIndex,
stack: &mut Vec<PointIndex>,
) {
- let Location { block, statement_index } = self.to_location(index);
+ let Location {
+ block,
+ statement_index,
+ } = self.to_location(index);
if statement_index == 0 {
// If this is a basic block head, then the predecessors are
// the the terminators of other basic blocks
stack.extend(
- mir
- .predecessors_for(block)
+ mir.predecessors_for(block)
.iter()
.map(|&pred_bb| mir.terminator_loc(pred_bb))
.map(|pred_loc| self.point_from_location(pred_loc)),
pub struct PointIndex { DEBUG_FORMAT = "PointIndex({})" }
}
-/// A single integer representing a (non-zero) `UniverseIndex`.
-/// Computed just by subtracting one from `UniverseIndex`; this is
-/// because the `0` value for `UniverseIndex` represents the root
-/// universe, and we don't need/want a bit for that one.
+/// A single integer representing a `ty::Placeholder`.
newtype_index! {
pub struct PlaceholderIndex { DEBUG_FORMAT = "PlaceholderIndex({})" }
}
/// A subuniverse from a subuniverse (e.g., instantiated from a
/// `for<'a> fn(&'a u32)` type).
- SubUniversalRegion(ty::UniverseIndex),
+ PlaceholderRegion(ty::Placeholder),
}
/// When we initially compute liveness, we use a bit matrix storing
/// Adds all the elements in the given bit array into the given
/// region. Returns true if any of them are newly added.
crate fn add_elements(&mut self, row: N, locations: &HybridBitSet<PointIndex>) -> bool {
- debug!("LivenessValues::add_elements(row={:?}, locations={:?})", row, locations);
+ debug!(
+ "LivenessValues::add_elements(row={:?}, locations={:?})",
+ row, locations
+ );
self.points.union_into_row(row, locations)
}
}
}
+/// Maps from `ty::Placeholder` values that are used in the rest of
+/// rustc to the internal `PlaceholderIndex` values that are used in
+/// NLL.
+#[derive(Default)]
+crate struct PlaceholderIndices {
+ to_index: FxHashMap<ty::Placeholder, PlaceholderIndex>,
+ from_index: IndexVec<PlaceholderIndex, ty::Placeholder>,
+}
+
+impl PlaceholderIndices {
+ crate fn insert(&mut self, placeholder: ty::Placeholder) -> PlaceholderIndex {
+ let PlaceholderIndices {
+ to_index,
+ from_index,
+ } = self;
+ *to_index
+ .entry(placeholder)
+ .or_insert_with(|| from_index.push(placeholder))
+ }
+
+ crate fn lookup_index(&self, placeholder: ty::Placeholder) -> PlaceholderIndex {
+ self.to_index[&placeholder]
+ }
+
+ crate fn lookup_placeholder(&self, placeholder: PlaceholderIndex) -> ty::Placeholder {
+ self.from_index[placeholder]
+ }
+
+ crate fn len(&self) -> usize {
+ self.from_index.len()
+ }
+}
+
+impl ::std::iter::FromIterator<ty::Placeholder> for PlaceholderIndices {
+ fn from_iter<I>(iter: I) -> Self
+ where
+ I: IntoIterator<Item = ty::Placeholder>,
+ {
+ let mut result = Self::default();
+ iter.into_iter().for_each(|p| {
+ result.insert(p);
+ });
+ result
+ }
+}
+
/// Stores the full values for a set of regions (in contrast to
/// `LivenessValues`, which only stores those points in the where a
/// region is live). The full value for a region may contain points in
#[derive(Clone)]
crate struct RegionValues<N: Idx> {
elements: Rc<RegionValueElements>,
+ placeholder_indices: Rc<PlaceholderIndices>,
points: SparseBitMatrix<N, PointIndex>,
free_regions: SparseBitMatrix<N, RegionVid>,
crate fn new(
elements: &Rc<RegionValueElements>,
num_universal_regions: usize,
- max_universe: ty::UniverseIndex,
+ placeholder_indices: PlaceholderIndices,
) -> Self {
- let num_placeholders = max_universe.as_usize();
+ let num_placeholders = placeholder_indices.len();
Self {
elements: elements.clone(),
points: SparseBitMatrix::new(elements.num_points),
+ placeholder_indices: Rc::new(placeholder_indices),
free_regions: SparseBitMatrix::new(num_universal_regions),
placeholders: SparseBitMatrix::new(num_placeholders),
}
/// Returns the locations contained within a given region `r`.
crate fn locations_outlived_by<'a>(&'a self, r: N) -> impl Iterator<Item = Location> + 'a {
- self.points
- .row(r)
- .into_iter()
- .flat_map(move |set| {
- set.iter()
- .take_while(move |&p| self.elements.point_in_range(p))
- .map(move |p| self.elements.to_location(p))
- })
+ self.points.row(r).into_iter().flat_map(move |set| {
+ set.iter()
+ .take_while(move |&p| self.elements.point_in_range(p))
+ .map(move |p| self.elements.to_location(p))
+ })
}
/// Returns just the universal regions that are contained in a given region's value.
}
/// Returns all the elements contained in a given region's value.
- crate fn subuniverses_contained_in<'a>(
+ crate fn placeholders_contained_in<'a>(
&'a self,
r: N,
- ) -> impl Iterator<Item = ty::UniverseIndex> + 'a {
+ ) -> impl Iterator<Item = ty::Placeholder> + 'a {
self.placeholders
.row(r)
.into_iter()
.flat_map(|set| set.iter())
- .map(|p| ty::UniverseIndex::from_u32((p.index() + 1) as u32))
+ .map(move |p| self.placeholder_indices.lookup_placeholder(p))
}
/// Returns all the elements contained in a given region's value.
crate fn elements_contained_in<'a>(&'a self, r: N) -> impl Iterator<Item = RegionElement> + 'a {
let points_iter = self.locations_outlived_by(r).map(RegionElement::Location);
- let free_regions_iter = self
- .universal_regions_outlived_by(r)
+ let free_regions_iter = self.universal_regions_outlived_by(r)
.map(RegionElement::RootUniversalRegion);
- let subuniverses_iter = self
- .subuniverses_contained_in(r)
- .map(RegionElement::SubUniversalRegion);
+ let placeholder_universes_iter = self.placeholders_contained_in(r)
+ .map(RegionElement::PlaceholderRegion);
points_iter
.chain(free_regions_iter)
- .chain(subuniverses_iter)
+ .chain(placeholder_universes_iter)
}
/// Returns a "pretty" string value of the region. Meant for debugging.
}
}
-impl ToElementIndex for ty::UniverseIndex {
+impl ToElementIndex for ty::Placeholder {
fn add_to_row<N: Idx>(self, values: &mut RegionValues<N>, row: N) -> bool {
- let index = PlaceholderIndex::new(self.as_usize() - 1);
+ let index = values.placeholder_indices.lookup_index(self);
values.placeholders.insert(row, index)
}
fn contained_in_row<N: Idx>(self, values: &RegionValues<N>, row: N) -> bool {
- let index = PlaceholderIndex::new(self.as_usize() - 1);
+ let index = values.placeholder_indices.lookup_index(self);
values.placeholders.contains(row, index)
}
}
result.push_str(&format!("{:?}", fr));
}
- RegionElement::SubUniversalRegion(ur) => {
+ RegionElement::PlaceholderRegion(placeholder) => {
if let Some((location1, location2)) = open_location {
push_sep(&mut result);
push_location_range(&mut result, location1, location2);
}
push_sep(&mut result);
- result.push_str(&format!("{:?}", ur));
+ result.push_str(&format!("{:?}", placeholder));
}
}
}
/// delegate.
fn push_outlives(&mut self, sup: ty::Region<'tcx>, sub: ty::Region<'tcx>);
- /// Creates a new region variable representing an instantiated
- /// higher-ranked region; this will be either existential or
- /// universal depending on the context. So e.g. if you have
- /// `for<'a> fn(..) <: for<'b> fn(..)`, then we will first
- /// instantiate `'b` with a universally quantitifed region and
- /// then `'a` with an existentially quantified region (the order
- /// is important so that the existential region `'a` can see the
- /// universal one).
- fn next_region_var(
- &mut self,
- universally_quantified: UniversallyQuantified,
- ) -> ty::Region<'tcx>;
+ /// Creates a new universe index. Used when instantiating placeholders.
+ fn next_subuniverse(&mut self) -> ty::UniverseIndex;
+
+ /// Creates a new region variable representing a higher-ranked
+ /// region that is instantiated existentially. This creates an
+ /// inference variable, typically.
+ ///
+ /// So e.g. if you have `for<'a> fn(..) <: for<'b> fn(..)`, then
+ /// we will invoke this method to instantiate `'a` with an
+ /// inference variable (though `'b` would be instantiated first,
+ /// as a placeholder).
+ fn next_existential_region_var(&mut self) -> ty::Region<'tcx>;
+
+ /// Creates a new region variable representing a
+ /// higher-ranked region that is instantiated universally.
+ /// This creates a new region placeholder, typically.
+ ///
+ /// So e.g. if you have `for<'a> fn(..) <: for<'b> fn(..)`, then
+ /// we will invoke this method to instantiate `'b` with a
+ /// placeholder region.
+ fn next_placeholder_region(&mut self, placeholder: ty::Placeholder) -> ty::Region<'tcx>;
/// Creates a new existential region in the given universe. This
/// is used when handling subtyping and type variables -- if we
}
impl TypeRelatingDelegate<'tcx> for NllTypeRelatingDelegate<'_, '_, '_, 'tcx> {
- fn next_region_var(
- &mut self,
- universally_quantified: UniversallyQuantified,
- ) -> ty::Region<'tcx> {
- let origin = if universally_quantified.0 {
- NLLRegionVariableOrigin::BoundRegion(self.infcx.create_subuniverse())
- } else {
- NLLRegionVariableOrigin::Existential
- };
+ fn next_subuniverse(&mut self) -> ty::UniverseIndex {
+ self.infcx.create_subuniverse()
+ }
+
+ fn next_existential_region_var(&mut self) -> ty::Region<'tcx> {
+ let origin = NLLRegionVariableOrigin::Existential;
+ self.infcx.next_nll_region_var(origin)
+ }
+
+ fn next_placeholder_region(&mut self, placeholder: ty::Placeholder) -> ty::Region<'tcx> {
+ let origin = NLLRegionVariableOrigin::Placeholder(placeholder);
self.infcx.next_nll_region_var(origin)
}
universally_quantified: UniversallyQuantified,
) -> BoundRegionScope<'tcx> {
let mut scope = BoundRegionScope::default();
+
+ // Create a callback that creates (via the delegate) either an
+ // existential or placeholder region as needed.
+ let mut next_region = {
+ let delegate = &mut self.delegate;
+ let mut lazy_universe = None;
+ move |br: ty::BoundRegion| {
+ if universally_quantified.0 {
+ // The first time this closure is called, create a
+ // new universe for the placeholders we will make
+ // from here out.
+ let universe = lazy_universe.unwrap_or_else(|| {
+ let universe = delegate.next_subuniverse();
+ lazy_universe = Some(universe);
+ universe
+ });
+
+ let placeholder = ty::Placeholder { universe, name: br };
+ delegate.next_placeholder_region(placeholder)
+ } else {
+ delegate.next_existential_region_var()
+ }
+ }
+ };
+
value.skip_binder().visit_with(&mut ScopeInstantiator {
- delegate: &mut self.delegate,
+ next_region: &mut next_region,
target_index: ty::INNERMOST,
- universally_quantified,
bound_region_scope: &mut scope,
});
+
scope
}
/// binder depth, and finds late-bound regions targeting the
/// `for<..`>. For each of those, it creates an entry in
/// `bound_region_scope`.
-struct ScopeInstantiator<'me, 'tcx: 'me, D>
-where
- D: TypeRelatingDelegate<'tcx> + 'me,
-{
- delegate: &'me mut D,
+struct ScopeInstantiator<'me, 'tcx: 'me> {
+ next_region: &'me mut dyn FnMut(ty::BoundRegion) -> ty::Region<'tcx>,
// The debruijn index of the scope we are instantiating.
target_index: ty::DebruijnIndex,
- universally_quantified: UniversallyQuantified,
bound_region_scope: &'me mut BoundRegionScope<'tcx>,
}
-impl<'me, 'tcx, D> TypeVisitor<'tcx> for ScopeInstantiator<'me, 'tcx, D>
-where
- D: TypeRelatingDelegate<'tcx>,
-{
+impl<'me, 'tcx> TypeVisitor<'tcx> for ScopeInstantiator<'me, 'tcx> {
fn visit_binder<T: TypeFoldable<'tcx>>(&mut self, t: &ty::Binder<T>) -> bool {
self.target_index.shift_in(1);
t.super_visit_with(self);
fn visit_region(&mut self, r: ty::Region<'tcx>) -> bool {
let ScopeInstantiator {
- universally_quantified,
bound_region_scope,
- delegate,
+ next_region,
..
} = self;
bound_region_scope
.map
.entry(*br)
- .or_insert_with(|| delegate.next_region_var(*universally_quantified));
+ .or_insert_with(|| next_region(*br));
}
_ => {}
projects / rust.git / commitdiff