pub enum ConstraintCategory<'tcx> {
Show 19 variants
Return(ReturnConstraint),
Yield,
UseAsConst,
UseAsStatic,
TypeAnnotation,
Cast {
is_implicit_coercion: bool,
unsize_to: Option<Ty<'tcx>>,
},
ClosureBounds,
CallArgument(Option<Ty<'tcx>>),
CopyBound,
SizedBound,
Assignment,
Usage,
OpaqueType,
ClosureUpvar(FieldIdx),
Predicate(Span),
Boring,
BoringNoLocation,
Internal,
IllegalUniverse,
}
Expand description
Outlives-constraints can be categorized to determine whether and why they are interesting (for error reporting). Order of variants indicates sort order of the category, thereby influencing diagnostic output.
See also rustc_const_eval::borrow_check::constraints
.
Variants§
Return(ReturnConstraint)
Yield
UseAsConst
UseAsStatic
TypeAnnotation
Cast
Fields
ClosureBounds
A constraint that came from checking the body of a closure.
We try to get the category that the closure used when reporting this.
CallArgument(Option<Ty<'tcx>>)
Contains the function type if available.
CopyBound
SizedBound
Assignment
Usage
A constraint that came from a usage of a variable (e.g. in an ADT expression
like Foo { field: my_val }
)
OpaqueType
ClosureUpvar(FieldIdx)
Predicate(Span)
A constraint from a user-written predicate
with the provided span, written on the item
with the given DefId
Boring
A “boring” constraint (caused by the given location) is one that the user probably doesn’t want to see described in diagnostics, because it is kind of an artifact of the type system setup.
BoringNoLocation
Internal
A constraint that doesn’t correspond to anything the user sees.
IllegalUniverse
An internal constraint derived from an illegal universe relation.
Trait Implementations§
source§impl<'tcx> Clone for ConstraintCategory<'tcx>
impl<'tcx> Clone for ConstraintCategory<'tcx>
source§fn clone(&self) -> ConstraintCategory<'tcx>
fn clone(&self) -> ConstraintCategory<'tcx>
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresource§impl<'tcx> Debug for ConstraintCategory<'tcx>
impl<'tcx> Debug for ConstraintCategory<'tcx>
source§impl<'tcx> Hash for ConstraintCategory<'tcx>
impl<'tcx> Hash for ConstraintCategory<'tcx>
source§impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for ConstraintCategory<'tcx>
impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for ConstraintCategory<'tcx>
fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher, )
source§impl<'tcx> Ord for ConstraintCategory<'tcx>
impl<'tcx> Ord for ConstraintCategory<'tcx>
source§impl<'tcx> PartialEq for ConstraintCategory<'tcx>
impl<'tcx> PartialEq for ConstraintCategory<'tcx>
source§impl<'tcx> PartialOrd for ConstraintCategory<'tcx>
impl<'tcx> PartialOrd for ConstraintCategory<'tcx>
source§impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for ConstraintCategory<'tcx>
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for ConstraintCategory<'tcx>
source§fn try_fold_with<__F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
__folder: &mut __F,
) -> Result<Self, __F::Error>
fn try_fold_with<__F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, __folder: &mut __F, ) -> Result<Self, __F::Error>
source§fn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<I>,
fn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<I>,
try_fold_with
for use with infallible
folders. Do not override this method, to ensure coherence with
try_fold_with
.source§impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for ConstraintCategory<'tcx>
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for ConstraintCategory<'tcx>
source§fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>(
&self,
__visitor: &mut __V,
) -> __V::Result
fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>( &self, __visitor: &mut __V, ) -> __V::Result
impl<'tcx> Copy for ConstraintCategory<'tcx>
impl<'tcx> Eq for ConstraintCategory<'tcx>
impl<'tcx> StructuralPartialEq for ConstraintCategory<'tcx>
Auto Trait Implementations§
impl<'tcx> Freeze for ConstraintCategory<'tcx>
impl<'tcx> !RefUnwindSafe for ConstraintCategory<'tcx>
impl<'tcx> !Send for ConstraintCategory<'tcx>
impl<'tcx> !Sync for ConstraintCategory<'tcx>
impl<'tcx> Unpin for ConstraintCategory<'tcx>
impl<'tcx> !UnwindSafe for ConstraintCategory<'tcx>
Blanket Implementations§
source§impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut T
fn allocate_from_iter( arena: &'tcx Arena<'tcx>, iter: impl IntoIterator<Item = T>, ) -> &'tcx mut [T]
source§impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut T
fn allocate_from_iter( arena: &'tcx Arena<'tcx>, iter: impl IntoIterator<Item = T>, ) -> &'tcx mut [T]
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)source§impl<T, R> CollectAndApply<T, R> for T
impl<T, R> CollectAndApply<T, R> for T
source§impl<Q, K> Comparable<K> for Q
impl<Q, K> Comparable<K> for Q
source§impl<Tcx, T> DepNodeParams<Tcx> for T
impl<Tcx, T> DepNodeParams<Tcx> for T
default fn fingerprint_style() -> FingerprintStyle
source§default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_debug_str(&self, _: Tcx) -> String
source§default fn recover(_: Tcx, _: &DepNode) -> Option<T>
default fn recover(_: Tcx, _: &DepNode) -> Option<T>
DepNode
,
something which is needed when forcing DepNode
s during red-green
evaluation. The query system will only call this method if
fingerprint_style()
is not FingerprintStyle::Opaque
.
It is always valid to return None
here, in which case incremental
compilation will treat the query as having changed instead of forcing it.source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§impl<Q, K> Equivalent<K> for Q
impl<Q, K> Equivalent<K> for Q
source§fn equivalent(&self, key: &K) -> bool
fn equivalent(&self, key: &K) -> bool
key
and return true
if they are equal.source§impl<T> Filterable for T
impl<T> Filterable for T
source§fn filterable(
self,
filter_name: &'static str,
) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>
fn filterable( self, filter_name: &'static str, ) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>
source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T> IntoEither for T
impl<T> IntoEither for T
source§fn into_either(self, into_left: bool) -> Either<Self, Self>
fn into_either(self, into_left: bool) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left
is true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
fn into_either_with<F>(self, into_left: F) -> Either<Self, Self>
self
into a Left
variant of Either<Self, Self>
if into_left(&self)
returns true
.
Converts self
into a Right
variant of Either<Self, Self>
otherwise. Read moresource§impl<P> IntoQueryParam<P> for P
impl<P> IntoQueryParam<P> for P
fn into_query_param(self) -> P
source§impl<'tcx, T> IsSuggestable<'tcx> for T
impl<'tcx, T> IsSuggestable<'tcx> for T
source§impl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
source§impl<I, T> TypeVisitableExt<I> for Twhere
I: Interner,
T: TypeVisitable<I>,
impl<I, T> TypeVisitableExt<I> for Twhere
I: Interner,
T: TypeVisitable<I>,
fn has_type_flags(&self, flags: TypeFlags) -> bool
source§fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
true
if self
has any late-bound regions that are either
bound by binder
or bound by some binder outside of binder
.
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, this indicates whether
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source§fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
true
if this type has any regions that escape binder
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hence are not bound by it).source§fn has_escaping_bound_vars(&self) -> bool
fn has_escaping_bound_vars(&self) -> bool
true
if this type has regions that are not a part of the type.
For example, for<'a> fn(&'a i32)
return false
, while fn(&'a i32)
would return true
. The latter can occur when traversing through the
former. Read morefn has_aliases(&self) -> bool
fn has_opaque_types(&self) -> bool
fn has_coroutines(&self) -> bool
fn references_error(&self) -> bool
fn has_non_region_param(&self) -> bool
fn has_infer_regions(&self) -> bool
fn has_infer_types(&self) -> bool
fn has_non_region_infer(&self) -> bool
fn has_infer(&self) -> bool
fn has_placeholders(&self) -> bool
fn has_non_region_placeholders(&self) -> bool
fn has_param(&self) -> bool
source§fn has_free_regions(&self) -> bool
fn has_free_regions(&self) -> bool
fn has_erased_regions(&self) -> bool
source§fn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
source§fn is_global(&self) -> bool
fn is_global(&self) -> bool
source§fn has_bound_regions(&self) -> bool
fn has_bound_regions(&self) -> bool
source§fn has_non_region_bound_vars(&self) -> bool
fn has_non_region_bound_vars(&self) -> bool
source§fn has_bound_vars(&self) -> bool
fn has_bound_vars(&self) -> bool
source§fn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
impl
specialization.source§impl<I, T, U> Upcast<I, U> for Twhere
U: UpcastFrom<I, T>,
impl<I, T, U> Upcast<I, U> for Twhere
U: UpcastFrom<I, T>,
source§impl<I, T> UpcastFrom<I, T> for T
impl<I, T> UpcastFrom<I, T> for T
fn upcast_from(from: T, _tcx: I) -> T
source§impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
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Tcx: DepContext,
default fn from_cycle_error( tcx: Tcx, cycle_error: &CycleError, _guar: ErrorGuaranteed, ) -> T
source§impl<T> WithSubscriber for T
impl<T> WithSubscriber for T
source§fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
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source§fn with_current_subscriber(self) -> WithDispatch<Self>
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T: 'static,
impl<T> MaybeSendSync for T
Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 16 bytes
Size for each variant:
Return
: 7 bytesYield
: 0 bytesUseAsConst
: 0 bytesUseAsStatic
: 0 bytesTypeAnnotation
: 0 bytesCast
: 15 bytesClosureBounds
: 0 bytesCallArgument
: 15 bytesCopyBound
: 0 bytesSizedBound
: 0 bytesAssignment
: 0 bytesUsage
: 0 bytesOpaqueType
: 0 bytesClosureUpvar
: 7 bytesPredicate
: 11 bytesBoring
: 0 bytesBoringNoLocation
: 0 bytesInternal
: 0 bytesIllegalUniverse
: 0 bytes