diff options
Diffstat (limited to 'compiler/rustc_infer/src/infer/mod.rs')
| -rw-r--r-- | compiler/rustc_infer/src/infer/mod.rs | 61 |
1 files changed, 32 insertions, 29 deletions
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs index 387843ee693..fb067e7ac21 100644 --- a/compiler/rustc_infer/src/infer/mod.rs +++ b/compiler/rustc_infer/src/infer/mod.rs @@ -114,24 +114,26 @@ pub struct InferCtxtInner<'tcx> { float_unification_storage: ut::UnificationTableStorage<ty::FloatVid>, /// Tracks the set of region variables and the constraints between them. + /// /// This is initially `Some(_)` but when /// `resolve_regions_and_report_errors` is invoked, this gets set to `None` /// -- further attempts to perform unification, etc., may fail if new /// region constraints would've been added. region_constraint_storage: Option<RegionConstraintStorage<'tcx>>, - /// A set of constraints that regionck must validate. Each - /// constraint has the form `T:'a`, meaning "some type `T` must + /// A set of constraints that regionck must validate. + /// + /// Each constraint has the form `T:'a`, meaning "some type `T` must /// outlive the lifetime 'a". These constraints derive from /// instantiated type parameters. So if you had a struct defined - /// like + /// like the following: /// ```ignore (illustrative) - /// struct Foo<T:'static> { ... } + /// struct Foo<T: 'static> { ... } /// ``` - /// then in some expression `let x = Foo { ... }` it will + /// In some expression `let x = Foo { ... }`, it will /// instantiate the type parameter `T` with a fresh type `$0`. At /// the same time, it will record a region obligation of - /// `$0:'static`. This will get checked later by regionck. (We + /// `$0: 'static`. This will get checked later by regionck. (We /// can't generally check these things right away because we have /// to wait until types are resolved.) /// @@ -268,7 +270,7 @@ pub struct InferCtxt<'tcx> { /// Caches the results of trait evaluation. pub evaluation_cache: select::EvaluationCache<'tcx>, - /// the set of predicates on which errors have been reported, to + /// The set of predicates on which errors have been reported, to /// avoid reporting the same error twice. pub reported_trait_errors: RefCell<FxIndexMap<Span, Vec<ty::Predicate<'tcx>>>>, @@ -291,7 +293,7 @@ pub struct InferCtxt<'tcx> { tainted_by_errors: Cell<Option<ErrorGuaranteed>>, /// Track how many errors were reported when this infcx is created. - /// If the number of errors increases, that's also a sign (line + /// If the number of errors increases, that's also a sign (like /// `tainted_by_errors`) to avoid reporting certain kinds of errors. // FIXME(matthewjasper) Merge into `tainted_by_errors` err_count_on_creation: usize, @@ -313,7 +315,7 @@ pub struct InferCtxt<'tcx> { /// During coherence we have to assume that other crates may add /// additional impls which we currently don't know about. /// - /// To deal with this evaluation should be conservative + /// To deal with this evaluation, we should be conservative /// and consider the possibility of impls from outside this crate. /// This comes up primarily when resolving ambiguity. Imagine /// there is some trait reference `$0: Bar` where `$0` is an @@ -323,7 +325,7 @@ pub struct InferCtxt<'tcx> { /// bound to some type that in a downstream crate that implements /// `Bar`. /// - /// Outside of coherence we set this to false because we are only + /// Outside of coherence, we set this to false because we are only /// interested in types that the user could actually have written. /// In other words, we consider `$0: Bar` to be unimplemented if /// there is no type that the user could *actually name* that @@ -373,7 +375,7 @@ pub enum SubregionOrigin<'tcx> { Subtype(Box<TypeTrace<'tcx>>), /// When casting `&'a T` to an `&'b Trait` object, - /// relating `'a` to `'b` + /// relating `'a` to `'b`. RelateObjectBound(Span), /// Some type parameter was instantiated with the given type, @@ -384,7 +386,7 @@ pub enum SubregionOrigin<'tcx> { /// that must outlive some other region. RelateRegionParamBound(Span), - /// Creating a pointer `b` to contents of another reference + /// Creating a pointer `b` to contents of another reference. Reborrow(Span), /// (&'a &'b T) where a >= b @@ -398,7 +400,7 @@ pub enum SubregionOrigin<'tcx> { trait_item_def_id: DefId, }, - /// Checking that the bounds of a trait's associated type hold for a given impl + /// Checking that the bounds of a trait's associated type hold for a given impl. CheckAssociatedTypeBounds { parent: Box<SubregionOrigin<'tcx>>, impl_item_def_id: LocalDefId, @@ -435,32 +437,33 @@ pub enum LateBoundRegionConversionTime { AssocTypeProjection(DefId), } -/// Reasons to create a region inference variable +/// Reasons to create a region inference variable. /// -/// See `error_reporting` module for more details +/// See `error_reporting` module for more details. #[derive(Copy, Clone, Debug)] pub enum RegionVariableOrigin { - /// Region variables created for ill-categorized reasons, - /// mostly indicates places in need of refactoring + /// Region variables created for ill-categorized reasons. + /// + /// They mostly indicate places in need of refactoring. MiscVariable(Span), - /// Regions created by a `&P` or `[...]` pattern + /// Regions created by a `&P` or `[...]` pattern. PatternRegion(Span), - /// Regions created by `&` operator + /// Regions created by `&` operator. + /// AddrOfRegion(Span), - - /// Regions created as part of an autoref of a method receiver + /// Regions created as part of an autoref of a method receiver. Autoref(Span), - /// Regions created as part of an automatic coercion + /// Regions created as part of an automatic coercion. Coercion(Span), - /// Region variables created as the values for early-bound regions + /// Region variables created as the values for early-bound regions. EarlyBoundRegion(Span, Symbol), /// Region variables created for bound regions - /// in a function or method that is called + /// in a function or method that is called. LateBoundRegion(Span, ty::BoundRegionKind, LateBoundRegionConversionTime), UpvarRegion(ty::UpvarId, Span), @@ -534,7 +537,7 @@ impl<'tcx> fmt::Display for FixupError<'tcx> { } } -/// Used to configure inference contexts before their creation +/// Used to configure inference contexts before their creation. pub struct InferCtxtBuilder<'tcx> { tcx: TyCtxt<'tcx>, defining_use_anchor: DefiningAnchor, @@ -835,9 +838,9 @@ impl<'tcx> InferCtxt<'tcx> { /// Scan the constraints produced since `snapshot` began and returns: /// - /// - `None` -- if none of them involve "region outlives" constraints - /// - `Some(true)` -- if there are `'a: 'b` constraints where `'a` or `'b` is a placeholder - /// - `Some(false)` -- if there are `'a: 'b` constraints but none involve placeholders + /// - `None` -- if none of them involves "region outlives" constraints. + /// - `Some(true)` -- if there are `'a: 'b` constraints where `'a` or `'b` is a placeholder. + /// - `Some(false)` -- if there are `'a: 'b` constraints but none involve placeholders. pub fn region_constraints_added_in_snapshot( &self, snapshot: &CombinedSnapshot<'tcx>, @@ -1770,7 +1773,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> { } } -/// Helper for `ty_or_const_infer_var_changed` (see comment on that), currently +/// Helper for [InferCtxt::ty_or_const_infer_var_changed] (see comment on that), currently /// used only for `traits::fulfill`'s list of `stalled_on` inference variables. #[derive(Copy, Clone, Debug)] pub enum TyOrConstInferVar<'tcx> { |