Struct rustc_middle::ty::Placeholder
source · [−]pub struct Placeholder<T> {
pub universe: UniverseIndex,
pub name: T,
}
Expand description
The “placeholder index” fully defines a placeholder region, type, or const. Placeholders are identified by both a universe, as well as a name residing within that universe. Distinct bound regions/types/consts within the same universe simply have an unknown relationship to one another.
Fields
universe: UniverseIndex
name: T
Trait Implementations
sourceimpl<T: Clone> Clone for Placeholder<T>
impl<T: Clone> Clone for Placeholder<T>
sourcefn clone(&self) -> Placeholder<T>
fn clone(&self) -> Placeholder<T>
Returns a copy of the value. Read more
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
Performs copy-assignment from source
. Read more
sourceimpl<T: Debug> Debug for Placeholder<T>
impl<T: Debug> Debug for Placeholder<T>
sourceimpl<'tcx, T, __D: TyDecoder<'tcx>> Decodable<__D> for Placeholder<T> where
T: Decodable<__D>,
impl<'tcx, T, __D: TyDecoder<'tcx>> Decodable<__D> for Placeholder<T> where
T: Decodable<__D>,
sourceimpl<'tcx, T, __E: TyEncoder<'tcx>> Encodable<__E> for Placeholder<T> where
T: Encodable<__E>,
impl<'tcx, T, __E: TyEncoder<'tcx>> Encodable<__E> for Placeholder<T> where
T: Encodable<__E>,
sourceimpl<T: Hash> Hash for Placeholder<T>
impl<T: Hash> Hash for Placeholder<T>
sourceimpl<'a, T> HashStable<StableHashingContext<'a>> for Placeholder<T> where
T: HashStable<StableHashingContext<'a>>,
impl<'a, T> HashStable<StableHashingContext<'a>> for Placeholder<T> where
T: HashStable<StableHashingContext<'a>>,
fn hash_stable(
&self,
hcx: &mut StableHashingContext<'a>,
hasher: &mut StableHasher
)
sourceimpl<'tcx> Lift<'tcx> for Placeholder<BoundRegionKind>
impl<'tcx> Lift<'tcx> for Placeholder<BoundRegionKind>
type Lifted = Placeholder<BoundRegionKind>
fn lift_to_tcx(self, _: TyCtxt<'tcx>) -> Option<Self>
sourceimpl<T: Ord> Ord for Placeholder<T>
impl<T: Ord> Ord for Placeholder<T>
sourceimpl<T: PartialEq> PartialEq<Placeholder<T>> for Placeholder<T>
impl<T: PartialEq> PartialEq<Placeholder<T>> for Placeholder<T>
sourcefn eq(&self, other: &Placeholder<T>) -> bool
fn eq(&self, other: &Placeholder<T>) -> bool
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
sourcefn ne(&self, other: &Placeholder<T>) -> bool
fn ne(&self, other: &Placeholder<T>) -> bool
This method tests for !=
.
sourceimpl<T: PartialOrd> PartialOrd<Placeholder<T>> for Placeholder<T>
impl<T: PartialOrd> PartialOrd<Placeholder<T>> for Placeholder<T>
sourcefn partial_cmp(&self, other: &Placeholder<T>) -> Option<Ordering>
fn partial_cmp(&self, other: &Placeholder<T>) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
1.0.0 · sourcefn lt(&self, other: &Rhs) -> bool
fn lt(&self, other: &Rhs) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
sourceimpl<'tcx> TypeFoldable<'tcx> for Placeholder<BoundRegionKind>
impl<'tcx> TypeFoldable<'tcx> for Placeholder<BoundRegionKind>
sourcefn try_super_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
_: &mut F
) -> Result<Placeholder<BoundRegionKind>, F::Error>
fn try_super_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
_: &mut F
) -> Result<Placeholder<BoundRegionKind>, F::Error>
Traverses the type in question, typically by calling try_fold_with
on
each field/element. This is true even for types of interest such as
Ty
. This should only be called within TypeFolder
methods, when
non-custom traversals are desired for types of interest. Read more
sourcefn super_visit_with<F: TypeVisitor<'tcx>>(
&self,
_: &mut F
) -> ControlFlow<F::BreakTy>
fn super_visit_with<F: TypeVisitor<'tcx>>(
&self,
_: &mut F
) -> ControlFlow<F::BreakTy>
Traverses the type in question, typically by calling visit_with
on
each field/element. This is true even for types of interest such as
Ty
. This should only be called within TypeVisitor
methods, when
non-custom traversals are desired for types of interest. Read more
sourcefn try_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
folder: &mut F
) -> Result<Self, F::Error>
fn try_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
folder: &mut F
) -> Result<Self, F::Error>
The main entry point for folding. To fold a value t
with a folder f
call: t.try_fold_with(f)
. Read more
sourcefn fold_with<F: TypeFolder<'tcx, Error = !>>(self, folder: &mut F) -> Self
fn fold_with<F: TypeFolder<'tcx, Error = !>>(self, folder: &mut F) -> Self
A convenient alternative to try_fold_with
for use with infallible
folders. Do not override this method, to ensure coherence with
try_fold_with
. Read more
sourcefn super_fold_with<F: TypeFolder<'tcx, Error = !>>(self, folder: &mut F) -> Self
fn super_fold_with<F: TypeFolder<'tcx, Error = !>>(self, folder: &mut F) -> Self
A convenient alternative to try_super_fold_with
for use with
infallible folders. Do not override this method, to ensure coherence
with try_super_fold_with
. Read more
sourcefn visit_with<V: TypeVisitor<'tcx>>(
&self,
visitor: &mut V
) -> ControlFlow<V::BreakTy>
fn visit_with<V: TypeVisitor<'tcx>>(
&self,
visitor: &mut V
) -> ControlFlow<V::BreakTy>
The entry point for visiting. To visit a value t
with a visitor v
call: t.visit_with(v)
. Read more
sourcefn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_at_or_above(&self, binder: DebruijnIndex) -> bool
Returns true
if self
has any late-bound regions that are either
bound by binder
or bound by some binder outside of binder
.
If binder
is ty::INNERMOST
, this indicates whether
there are any late-bound regions that appear free. Read more
sourcefn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
Returns true
if this self
has any regions that escape binder
(and
hence are not bound by it). Read more
fn has_escaping_bound_vars(&self) -> bool
fn has_type_flags(&self, flags: TypeFlags) -> bool
fn has_projections(&self) -> bool
fn has_opaque_types(&self) -> bool
fn references_error(&self) -> bool
fn error_reported(&self) -> Option<ErrorGuaranteed>
fn has_param_types_or_consts(&self) -> bool
fn has_infer_regions(&self) -> bool
fn has_infer_types(&self) -> bool
fn has_infer_types_or_consts(&self) -> bool
fn needs_infer(&self) -> bool
fn has_placeholders(&self) -> bool
fn needs_subst(&self) -> bool
sourcefn has_free_regions(&self) -> bool
fn has_free_regions(&self) -> bool
“Free” regions in this context means that it has any region that is not (a) erased or (b) late-bound. Read more
fn has_erased_regions(&self) -> bool
sourcefn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
True if there are any un-erased free regions.
sourcefn is_global(&self) -> bool
fn is_global(&self) -> bool
Indicates whether this value references only ‘global’ generic parameters that are the same regardless of what fn we are in. This is used for caching. Read more
sourcefn has_late_bound_regions(&self) -> bool
fn has_late_bound_regions(&self) -> bool
True if there are any late-bound regions
sourcefn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
Indicates whether this value still has parameters/placeholders/inference variables
which could be replaced later, in a way that would change the results of impl
specialization. Read more
impl<T: Copy> Copy for Placeholder<T>
impl<T: Eq> Eq for Placeholder<T>
impl<T> StructuralEq for Placeholder<T>
impl<T> StructuralPartialEq for Placeholder<T>
Auto Trait Implementations
impl<T> RefUnwindSafe for Placeholder<T> where
T: RefUnwindSafe,
impl<T> Send for Placeholder<T> where
T: Send,
impl<T> Sync for Placeholder<T> where
T: Sync,
impl<T> Unpin for Placeholder<T> where
T: Unpin,
impl<T> UnwindSafe for Placeholder<T> where
T: UnwindSafe,
Blanket Implementations
sourceimpl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for T where
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for T where
T: Copy,
fn allocate_on(self, arena: &'a Arena<'tcx>) -> &'a mut T
fn allocate_from_iter(
arena: &'a Arena<'tcx>,
iter: impl IntoIterator<Item = T>
) -> &'a mut [T]ⓘNotable traits for &'_ [u8]impl<'_> Read for &'_ [u8]impl<'_> Write for &'_ mut [u8]
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<Ctxt, T> DepNodeParams<Ctxt> for T where
Ctxt: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
impl<Ctxt, T> DepNodeParams<Ctxt> for T where
Ctxt: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
default fn fingerprint_style() -> FingerprintStyle
sourcedefault fn to_fingerprint(&self, tcx: Ctxt) -> Fingerprint
default fn to_fingerprint(&self, tcx: Ctxt) -> Fingerprint
This method turns the parameters of a DepNodeConstructor into an opaque Fingerprint to be used in DepNode. Not all DepNodeParams support being turned into a Fingerprint (they don’t need to if the corresponding DepNode is anonymous). Read more
default fn to_debug_str(&self, Ctxt) -> String
sourcedefault fn recover(Ctxt, &DepNode<<Ctxt as DepContext>::DepKind>) -> Option<T>
default fn recover(Ctxt, &DepNode<<Ctxt as DepContext>::DepKind>) -> Option<T>
This method tries to recover the query key from the given 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. Read more
sourceimpl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcefn clone_into(&self, target: &mut T)
fn clone_into(&self, target: &mut T)
toowned_clone_into
)Uses borrowed data to replace owned data, usually by cloning. Read more
impl<'a, T> Captures<'a> for T where
T: ?Sized,
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.