Struct chalk_solve::infer::unify::OccursCheck

source ·
struct OccursCheck<'u, 't, I: Interner> {
    unifier: &'u mut Unifier<'t, I>,
    var: EnaVariable<I>,
    universe_index: UniverseIndex,
}

Fields§

§unifier: &'u mut Unifier<'t, I>§var: EnaVariable<I>§universe_index: UniverseIndex

Implementations§

source§

impl<'u, 't, I: Interner> OccursCheck<'u, 't, I>

source

fn new( unifier: &'u mut Unifier<'t, I>, var: EnaVariable<I>, universe_index: UniverseIndex, ) -> Self

Trait Implementations§

source§

impl<'i, I: Interner> FallibleTypeFolder<I> for OccursCheck<'_, 'i, I>

§

type Error = NoSolution

The type this folder returns when folding fails. This is commonly NoSolution.
source§

fn as_dyn(&mut self) -> &mut dyn FallibleTypeFolder<I, Error = Self::Error>

Creates a dyn value from this folder. Unfortunately, this must be added manually to each impl of FallibleTypeFolder; it permits the default implements below to create a &mut dyn FallibleTypeFolder from Self without knowing what Self is (by invoking this method). Effectively, this limits impls of FallibleTypeFolder to types for which we are able to create a dyn value (i.e., not [T] types).
source§

fn try_fold_free_placeholder_ty( &mut self, universe: PlaceholderIndex, _outer_binder: DebruijnIndex, ) -> Fallible<Ty<I>>

Invoked for each occurrence of a placeholder type; these are used when we instantiate binders universally. Returns a type to use instead, which should be suitably shifted to account for binders. Read more
source§

fn try_fold_free_placeholder_const( &mut self, ty: Ty<I>, universe: PlaceholderIndex, _outer_binder: DebruijnIndex, ) -> Fallible<Const<I>>

As with try_fold_free_placeholder_ty, but for constants.
source§

fn try_fold_free_placeholder_lifetime( &mut self, ui: PlaceholderIndex, _outer_binder: DebruijnIndex, ) -> Fallible<Lifetime<I>>

As with try_fold_free_placeholder_ty, but for lifetimes.
source§

fn try_fold_inference_ty( &mut self, var: InferenceVar, kind: TyVariableKind, _outer_binder: DebruijnIndex, ) -> Fallible<Ty<I>>

Invoked for each occurrence of a inference type; these are used when we instantiate binders universally. Returns a type to use instead, which should be suitably shifted to account for binders. Read more
source§

fn try_fold_inference_const( &mut self, ty: Ty<I>, var: InferenceVar, _outer_binder: DebruijnIndex, ) -> Fallible<Const<I>>

As with try_fold_inference_ty, but for constants.
source§

fn try_fold_inference_lifetime( &mut self, var: InferenceVar, outer_binder: DebruijnIndex, ) -> Fallible<Lifetime<I>>

As with try_fold_inference_ty, but for lifetimes.
source§

fn forbid_free_vars(&self) -> bool

If overridden to return true, then folding will panic if a free variable is encountered. This should be done if free type/lifetime variables are not expected.
source§

fn interner(&self) -> I

Gets the interner that is being folded from.
source§

fn try_fold_ty( &mut self, ty: Ty<I>, outer_binder: DebruijnIndex, ) -> Result<Ty<I>, Self::Error>

Top-level callback: invoked for each Ty<I> that is encountered when folding. By default, invokes try_super_fold_with, which will in turn invoke the more specialized folding methods below, like try_fold_free_var_ty.
source§

fn try_fold_lifetime( &mut self, lifetime: Lifetime<I>, outer_binder: DebruijnIndex, ) -> Result<Lifetime<I>, Self::Error>

Top-level callback: invoked for each Lifetime<I> that is encountered when folding. By default, invokes try_super_fold_with, which will in turn invoke the more specialized folding methods below, like try_fold_free_var_lifetime.
source§

fn try_fold_const( &mut self, constant: Const<I>, outer_binder: DebruijnIndex, ) -> Result<Const<I>, Self::Error>

Top-level callback: invoked for each Const<I> that is encountered when folding. By default, invokes try_super_fold_with, which will in turn invoke the more specialized folding methods below, like try_fold_free_var_const.
source§

fn try_fold_program_clause( &mut self, clause: ProgramClause<I>, outer_binder: DebruijnIndex, ) -> Result<ProgramClause<I>, Self::Error>

Invoked for every program clause. By default, recursively folds the goals contents.
source§

fn try_fold_goal( &mut self, goal: Goal<I>, outer_binder: DebruijnIndex, ) -> Result<Goal<I>, Self::Error>

Invoked for every goal. By default, recursively folds the goals contents.
source§

fn try_fold_free_var_ty( &mut self, bound_var: BoundVar, outer_binder: DebruijnIndex, ) -> Result<Ty<I>, Self::Error>

Invoked for TyKind::BoundVar instances that are not bound within the type being folded over: Read more
source§

fn try_fold_free_var_lifetime( &mut self, bound_var: BoundVar, outer_binder: DebruijnIndex, ) -> Result<Lifetime<I>, Self::Error>

As try_fold_free_var_ty, but for lifetimes.
source§

fn try_fold_free_var_const( &mut self, ty: Ty<I>, bound_var: BoundVar, outer_binder: DebruijnIndex, ) -> Result<Const<I>, Self::Error>

As try_fold_free_var_ty, but for constants.
source§

fn forbid_free_placeholders(&self) -> bool

If overridden to return true, we will panic when a free placeholder type/lifetime/const is encountered.
source§

fn forbid_inference_vars(&self) -> bool

If overridden to return true, inference variables will trigger panics when folded. Used when inference variables are unexpected.

Auto Trait Implementations§

§

impl<'u, 't, I> Freeze for OccursCheck<'u, 't, I>

§

impl<'u, 't, I> !RefUnwindSafe for OccursCheck<'u, 't, I>

§

impl<'u, 't, I> !Send for OccursCheck<'u, 't, I>

§

impl<'u, 't, I> !Sync for OccursCheck<'u, 't, I>

§

impl<'u, 't, I> Unpin for OccursCheck<'u, 't, I>
where I: Unpin,

§

impl<'u, 't, I> !UnwindSafe for OccursCheck<'u, 't, I>

Blanket Implementations§

source§

impl<T> Any for T
where T: 'static + ?Sized,

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for T
where T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
source§

impl<T> Cast for T

source§

fn cast<U>(self, interner: <U as HasInterner>::Interner) -> U
where Self: CastTo<U>, U: HasInterner,

Cast a value to type U using CastTo.
source§

impl<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

§

impl<T> Instrument for T

§

fn instrument(self, span: Span) -> Instrumented<Self>

Instruments this type with the provided [Span], returning an Instrumented wrapper. Read more
§

fn in_current_span(self) -> Instrumented<Self>

Instruments this type with the current Span, returning an Instrumented wrapper. Read more
source§

impl<T, U> Into<U> for T
where U: From<T>,

source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
§

impl<T> WithSubscriber for T

§

fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>
where S: Into<Dispatch>,

Attaches the provided Subscriber to this type, returning a [WithDispatch] wrapper. Read more
§

fn with_current_subscriber(self) -> WithDispatch<Self>

Attaches the current default Subscriber to this type, returning a [WithDispatch] wrapper. Read more