Enum rustc_infer::infer::region_constraints::VerifyBound
source · pub enum VerifyBound<'tcx> {
IfEq(Binder<'tcx, VerifyIfEq<'tcx>>),
OutlivedBy(Region<'tcx>),
IsEmpty,
AnyBound(Vec<VerifyBound<'tcx>>),
AllBounds(Vec<VerifyBound<'tcx>>),
}
Expand description
Describes the things that some GenericKind
value G
is known to
outlive. Each variant of VerifyBound
can be thought of as a
function:
fn(min: Region) -> bool { .. }
where true
means that the region min
meets that G: min
.
(False means nothing.)
So, for example, if we have the type T
and we have in scope that
T: 'a
and T: 'b
, then the verify bound might be:
fn(min: Region) -> bool {
('a: min) || ('b: min)
}
This is described with an AnyRegion('a, 'b)
node.
Variants§
IfEq(Binder<'tcx, VerifyIfEq<'tcx>>)
See VerifyIfEq
docs
OutlivedBy(Region<'tcx>)
Given a region R
, expands to the function:
fn(min) -> bool {
R: min
}
This is used when we can establish that G: R
– therefore,
if R: min
, then by transitivity G: min
.
IsEmpty
Given a region R
, true if it is 'empty
.
AnyBound(Vec<VerifyBound<'tcx>>)
Given a set of bounds B
, expands to the function:
fn(min) -> bool {
exists (b in B) { b(min) }
}
In other words, if we meet some bound in B
, that suffices.
This is used when all the bounds in B
are known to apply to G
.
AllBounds(Vec<VerifyBound<'tcx>>)
Given a set of bounds B
, expands to the function:
fn(min) -> bool {
forall (b in B) { b(min) }
}
In other words, if we meet all bounds in B
, that suffices.
This is used when some bound in B
is known to suffice, but
we don’t know which.
Implementations§
source§impl<'tcx> VerifyBound<'tcx>
impl<'tcx> VerifyBound<'tcx>
pub fn must_hold(&self) -> bool
pub fn cannot_hold(&self) -> bool
pub fn or(self, vb: VerifyBound<'tcx>) -> VerifyBound<'tcx>
Trait Implementations§
source§impl<'tcx> Clone for VerifyBound<'tcx>
impl<'tcx> Clone for VerifyBound<'tcx>
source§fn clone(&self) -> VerifyBound<'tcx>
fn clone(&self) -> VerifyBound<'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 VerifyBound<'tcx>
impl<'tcx> Debug for VerifyBound<'tcx>
source§impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for VerifyBound<'tcx>
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for VerifyBound<'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 VerifyBound<'tcx>
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for VerifyBound<'tcx>
source§fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>(
&self,
__visitor: &mut __V
) -> ControlFlow<__V::BreakTy>
fn visit_with<__V: TypeVisitor<TyCtxt<'tcx>>>( &self, __visitor: &mut __V ) -> ControlFlow<__V::BreakTy>
Auto Trait Implementations§
impl<'tcx> !RefUnwindSafe for VerifyBound<'tcx>
impl<'tcx> Send for VerifyBound<'tcx>
impl<'tcx> Sync for VerifyBound<'tcx>
impl<'tcx> Unpin for VerifyBound<'tcx>
impl<'tcx> !UnwindSafe for VerifyBound<'tcx>
Blanket Implementations§
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
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: 32 bytes
Size for each variant:
IfEq
: 24 bytesOutlivedBy
: 8 bytesIsEmpty
: 0 bytesAnyBound
: 24 bytesAllBounds
: 24 bytes