Struct rustc_infer::infer::region_constraints::VerifyIfEq
source · Expand description
This is a “conditional bound” that checks the result of inference and supplies a bound if it ended up being relevant. It’s used in situations like this:
fn foo<'a, 'b, T: SomeTrait<'a>>
where
<T as SomeTrait<'a>>::Item: 'b
If we have an obligation like <T as SomeTrait<'?x>>::Item: 'c
, then
we don’t know yet whether it suffices to show that 'b: 'c
. If '?x
winds
up being equal to 'a
, then the where-clauses on function applies, and
in that case we can show 'b: 'c
. But if '?x
winds up being something
else, the bound isn’t relevant.
In the VerifyBound
, this struct is enclosed in `Binder to account
for cases like
where for<'a> <T as SomeTrait<'a>::Item: 'a
The idea is that we have to find some instantiation of 'a
that can
make <T as SomeTrait<'a>>::Item
equal to the final value of G
,
the generic we are checking.
fn(min) -> bool {
exists<'a> {
if G == K {
B(min)
} else {
false
}
}
}
Fields
ty: Ty<'tcx>
Type which must match the generic G
bound: Region<'tcx>
Bound that applies if ty
is equal.
Trait Implementations
sourceimpl<'tcx> Clone for VerifyIfEq<'tcx>
impl<'tcx> Clone for VerifyIfEq<'tcx>
sourcefn clone(&self) -> VerifyIfEq<'tcx>
fn clone(&self) -> VerifyIfEq<'tcx>
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresourceimpl<'tcx> Debug for VerifyIfEq<'tcx>
impl<'tcx> Debug for VerifyIfEq<'tcx>
sourceimpl<'tcx> TypeFoldable<'tcx> for VerifyIfEq<'tcx>
impl<'tcx> TypeFoldable<'tcx> for VerifyIfEq<'tcx>
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>
sourcefn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<'tcx>,
fn fold_with<F>(self, folder: &mut F) -> Selfwhere
F: TypeFolder<'tcx>,
try_fold_with
for use with infallible
folders. Do not override this method, to ensure coherence with
try_fold_with
. Read moresourceimpl<'tcx> TypeVisitable<'tcx> for VerifyIfEq<'tcx>
impl<'tcx> TypeVisitable<'tcx> for VerifyIfEq<'tcx>
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>
sourcefn 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
.
If binder
is ty::INNERMOST
, this indicates whether
there are any late-bound regions that appear free. Read moresourcefn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
true
if this self
has any regions that escape binder
(and
hence are not bound by it). Read morefn 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
fn has_erased_regions(&self) -> bool
sourcefn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
sourcefn is_global(&self) -> bool
fn is_global(&self) -> bool
sourcefn has_late_bound_regions(&self) -> bool
fn has_late_bound_regions(&self) -> bool
sourcefn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
impl
specialization. Read moreimpl<'tcx> Copy for VerifyIfEq<'tcx>
Auto Trait Implementations
impl<'tcx> !RefUnwindSafe for VerifyIfEq<'tcx>
impl<'tcx> Send for VerifyIfEq<'tcx>
impl<'tcx> Sync for VerifyIfEq<'tcx>
impl<'tcx> Unpin for VerifyIfEq<'tcx>
impl<'tcx> !UnwindSafe for VerifyIfEq<'tcx>
Blanket Implementations
sourceimpl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
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 Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
sourceimpl<'tcx, T> IsSuggestable<'tcx> for Twhere
T: TypeVisitable<'tcx>,
impl<'tcx, T> IsSuggestable<'tcx> for Twhere
T: TypeVisitable<'tcx>,
impl<'a, T> Captures<'a> for Twhere
T: ?Sized,
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