Enum rustc_trait_selection::infer::NllRegionVariableOrigin

source ·

pub enum NllRegionVariableOrigin {
    FreeRegion,
    Placeholder(Placeholder<BoundRegion>),
    Existential {
        from_forall: bool,
    },
}

Variants§

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FreeRegion

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.

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Placeholder(Placeholder<BoundRegion>)

“Universal” instantiation of a higher-ranked region (e.g., from a for<'a> T binder). Meant to represent “any region”.

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Existential

Fields

§from_forall: bool

If this is true, then this variable was created to represent a lifetime bound in a for binder. For example, it might have been created to represent the lifetime 'a in a type like for<'a> fn(&'a u32). Such variables are created when we are trying to figure out if there is any valid instantiation of 'a that could fit into some scenario.

This is used to inform error reporting: in the case that we are trying to determine whether there is any valid instantiation of a 'a variable that meets some constraint C, we want to blame the “source” of that for type, rather than blaming the source of the constraint C.

Enum rustc_trait_selection::infer::NllRegionVariableOrigin

Variants§

FreeRegion

Placeholder(Placeholder<BoundRegion>)

Existential

Fields

Trait Implementations§

impl Clone for NllRegionVariableOrigin

fn clone(&self) -> NllRegionVariableOrigin

fn clone_from(&mut self, source: &Self)

impl Debug for NllRegionVariableOrigin

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

impl Copy for NllRegionVariableOrigin

Auto Trait Implementations§

impl DynSend for NllRegionVariableOrigin

impl DynSync for NllRegionVariableOrigin

impl Freeze for NllRegionVariableOrigin

impl RefUnwindSafe for NllRegionVariableOrigin

impl Send for NllRegionVariableOrigin

impl Sync for NllRegionVariableOrigin

impl Unpin for NllRegionVariableOrigin

impl UnwindSafe for NllRegionVariableOrigin

Blanket Implementations§

impl<T> Aligned for T

const ALIGN: Alignment = _

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

fn type_id(&self) -> TypeId

impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere T: Copy,

fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut T

fn allocate_from_iter<'a>( arena: &'a Arena<'tcx>, iter: impl IntoIterator<Item = T> ) -> &'a mut [T]

impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere T: Copy,

fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut T

fn allocate_from_iter<'a>( arena: &'a Arena<'tcx>, iter: impl IntoIterator<Item = T> ) -> &'a mut [T]

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

fn borrow(&self) -> &T

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

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

impl<T, R> CollectAndApply<T, R> for T

fn collect_and_apply<I, F>(iter: I, f: F) -> Rwhere I: Iterator<Item = T>, F: FnOnce(&[T]) -> R,

type Output = R

impl<T> Filterable for T

fn filterable( self, filter_name: &'static str ) -> RequestFilterDataProvider<T, fn(_: DataRequest<'_>) -> bool>

impl<T> From<T> for T

fn from(t: T) -> T

impl<T> Instrument for T

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

fn in_current_span(self) -> Instrumented<Self>

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

fn into(self) -> U

impl<P> IntoQueryParam<P> for P

fn into_query_param(self) -> P

impl<T> MaybeResult<T> for T

type Error = !

fn from(_: Result<T, <T as MaybeResult<T>>::Error>) -> T

fn to_result(self) -> Result<T, <T as MaybeResult<T>>::Error>

impl<T> Pointable for T

const ALIGN: usize = _

type Init = T

unsafe fn init(init: <T as Pointable>::Init) -> usize

unsafe fn deref<'a>(ptr: usize) -> &'a T

unsafe fn deref_mut<'a>(ptr: usize) -> &'a mut T

unsafe fn drop(ptr: usize)

impl<T> Same for T

type Output = T

impl<T> ToOwned for Twhere T: Clone,

type Owned = T

fn to_owned(&self) -> T

fn clone_into(&self, target: &mut T)

impl<'tcx, T> ToPredicate<'tcx, T> for T

fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T

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

type Error = Infallible

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

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

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

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

impl<V, T> VZip<V> for Twhere V: MultiLane<T>,

fn vzip(self) -> V

impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,

default fn from_cycle_error( tcx: Tcx, cycle_error: &CycleError, _guar: ErrorGuaranteed ) -> T

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

impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for T
where T: Copy,

impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for T
where T: Copy,

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

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

fn collect_and_apply<I, F>(iter: I, f: F) -> R
where I: Iterator<Item = T>, F: FnOnce(&[T]) -> R,

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

impl<T> ToOwned for T
where T: Clone,

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

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

impl<V, T> VZip<V> for T
where V: MultiLane<T>,

impl<Tcx, T> Value<Tcx> for T
where Tcx: DepContext,

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

impl<'a, T> Captures<'a> for T
where T: ?Sized,

impl<T> ErasedDestructor for T
where T: 'static,

impl<T> MaybeSendSync for T
where T: Send + Sync,