Enum rustc_middle::thir::PatKind
source · [−]pub enum PatKind<'tcx> {
Wild,
AscribeUserType {
ascription: Ascription<'tcx>,
subpattern: Pat<'tcx>,
},
Binding {
mutability: Mutability,
name: Symbol,
mode: BindingMode,
var: LocalVarId,
ty: Ty<'tcx>,
subpattern: Option<Pat<'tcx>>,
is_primary: bool,
},
Variant {
adt_def: AdtDef<'tcx>,
substs: SubstsRef<'tcx>,
variant_index: VariantIdx,
subpatterns: Vec<FieldPat<'tcx>>,
},
Leaf {
subpatterns: Vec<FieldPat<'tcx>>,
},
Deref {
subpattern: Pat<'tcx>,
},
Constant {
value: ConstantKind<'tcx>,
},
Range(PatRange<'tcx>),
Slice {
prefix: Vec<Pat<'tcx>>,
slice: Option<Pat<'tcx>>,
suffix: Vec<Pat<'tcx>>,
},
Array {
prefix: Vec<Pat<'tcx>>,
slice: Option<Pat<'tcx>>,
suffix: Vec<Pat<'tcx>>,
},
Or {
pats: Vec<Pat<'tcx>>,
},
}
Variants
Wild
A wildcard pattern: _
.
AscribeUserType
Binding
Fields
mutability: Mutability
name: Symbol
mode: BindingMode
var: LocalVarId
ty: Ty<'tcx>
is_primary: bool
Is this the leftmost occurrence of the binding, i.e., is var
the
HirId
of this pattern?
x
, ref x
, x @ P
, etc.
Variant
Foo(...)
or Foo{...}
or Foo
, where Foo
is a variant name from an ADT with
multiple variants.
Leaf
(...)
, Foo(...)
, Foo{...}
, or Foo
, where Foo
is a variant name from an ADT with
a single variant.
Deref
Fields
subpattern: Pat<'tcx>
box P
, &P
, &mut P
, etc.
Constant
Fields
value: ConstantKind<'tcx>
One of the following:
&str
, which will be handled as a string pattern and thus exhaustiveness checking will detect if you use the same string twice in different patterns.- integer, bool, char or float, which will be handled by exhaustiveness to cover exactly
its own value, similar to
&str
, but these values are much simpler. - Opaque constants, that must not be matched structurally. So anything that does not derive
PartialEq
andEq
.
Range(PatRange<'tcx>)
Slice
Matches against a slice, checking the length and extracting elements.
irrefutable when there is a slice pattern and both prefix
and suffix
are empty.
e.g., &[ref xs @ ..]
.
Array
Fixed match against an array; irrefutable.
Or
An or-pattern, e.g. p | q
.
Invariant: pats.len() >= 2
.
Trait Implementations
sourceimpl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for PatKind<'tcx>
impl<'tcx, '__ctx> HashStable<StableHashingContext<'__ctx>> for PatKind<'tcx>
fn hash_stable(
&self,
__hcx: &mut StableHashingContext<'__ctx>,
__hasher: &mut StableHasher
)
Auto Trait Implementations
impl<'tcx> !RefUnwindSafe for PatKind<'tcx>
impl<'tcx> !Send for PatKind<'tcx>
impl<'tcx> !Sync for PatKind<'tcx>
impl<'tcx> Unpin for PatKind<'tcx>
impl<'tcx> !UnwindSafe for PatKind<'tcx>
Blanket Implementations
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, R> InternIteratorElement<T, R> for T
impl<T, R> InternIteratorElement<T, R> for T
type Output = R
fn intern_with<I, F>(iter: I, f: F) -> <T as InternIteratorElement<T, R>>::Output where
I: Iterator<Item = T>,
F: FnOnce(&[T]) -> R,
sourceimpl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
impl<'a, T> Captures<'a> for T where
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: 112 bytes
Size for each variant:
Wild
: 0 bytesAscribeUserType
: 111 bytesBinding
: 47 bytesVariant
: 47 bytesLeaf
: 31 bytesDeref
: 31 bytesConstant
: 55 bytesRange
: 111 bytesSlice
: 79 bytesArray
: 79 bytesOr
: 31 bytes