Struct rustc_middle::middle::region::Scope
source · pub struct Scope {
pub id: ItemLocalId,
pub data: ScopeData,
}
Expand description
Represents a statically-describable scope that can be used to bound the lifetime/region for values.
Node(node_id)
: Any AST node that has any scope at all has the
Node(node_id)
scope. Other variants represent special cases not
immediately derivable from the abstract syntax tree structure.
DestructionScope(node_id)
represents the scope of destructors
implicitly-attached to node_id
that run immediately after the
expression for node_id
itself. Not every AST node carries a
DestructionScope
, but those that are terminating_scopes
do;
see discussion with ScopeTree
.
Remainder { block, statement_index }
represents
the scope of user code running immediately after the initializer
expression for the indexed statement, until the end of the block.
So: the following code can be broken down into the scopes beneath:
let a = f().g( 'b: { let x = d(); let y = d(); x.h(y) } ) ;
+-+ (D12.)
+-+ (D11.)
+---------+ (R10.)
+-+ (D9.)
+----------+ (M8.)
+----------------------+ (R7.)
+-+ (D6.)
+----------+ (M5.)
+-----------------------------------+ (M4.)
+--------------------------------------------------+ (M3.)
+--+ (M2.)
+-----------------------------------------------------------+ (M1.)
(M1.): Node scope of the whole `let a = ...;` statement.
(M2.): Node scope of the `f()` expression.
(M3.): Node scope of the `f().g(..)` expression.
(M4.): Node scope of the block labeled `'b:`.
(M5.): Node scope of the `let x = d();` statement
(D6.): DestructionScope for temporaries created during M5.
(R7.): Remainder scope for block `'b:`, stmt 0 (let x = ...).
(M8.): Node scope of the `let y = d();` statement.
(D9.): DestructionScope for temporaries created during M8.
(R10.): Remainder scope for block `'b:`, stmt 1 (let y = ...).
(D11.): DestructionScope for temporaries and bindings from block `'b:`.
(D12.): DestructionScope for temporaries created during M1 (e.g., f()).
Note that while the above picture shows the destruction scopes as following their corresponding node scopes, in the internal data structures of the compiler the destruction scopes are represented as enclosing parents. This is sound because we use the enclosing parent relationship just to ensure that referenced values live long enough; phrased another way, the starting point of each range is not really the important thing in the above picture, but rather the ending point.
Fields
id: ItemLocalId
data: ScopeData
Implementations
sourceimpl Scope
impl Scope
sourcepub fn item_local_id(&self) -> ItemLocalId
pub fn item_local_id(&self) -> ItemLocalId
Returns an item-local ID associated with this scope.
N.B., likely to be replaced as API is refined; e.g., pnkfelix
anticipates fn entry_node_id
and fn each_exit_node_id
.
pub fn hir_id(&self, scope_tree: &ScopeTree) -> Option<HirId>
Trait Implementations
sourceimpl<'__ctx> HashStable<StableHashingContext<'__ctx>> for Scope
impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for Scope
fn hash_stable(
&self,
__hcx: &mut StableHashingContext<'__ctx>,
__hasher: &mut StableHasher
)
sourceimpl Ord for Scope
impl Ord for Scope
1.21.0 · sourcefn max(self, other: Self) -> Self
fn max(self, other: Self) -> Self
1.21.0 · sourcefn min(self, other: Self) -> Self
fn min(self, other: Self) -> Self
1.50.0 · sourcefn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
fn clamp(self, min: Self, max: Self) -> Selfwhere
Self: PartialOrd<Self>,
sourceimpl PartialOrd<Scope> for Scope
impl PartialOrd<Scope> for Scope
sourcefn partial_cmp(&self, other: &Scope) -> Option<Ordering>
fn partial_cmp(&self, other: &Scope) -> Option<Ordering>
1.0.0 · sourcefn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresourceimpl<'a> ToStableHashKey<StableHashingContext<'a>> for Scope
impl<'a> ToStableHashKey<StableHashingContext<'a>> for Scope
type KeyType = Scope
fn to_stable_hash_key(&self, _: &StableHashingContext<'a>) -> Scope
sourceimpl<'tcx> TypeFoldable<'tcx> for Scope
impl<'tcx> TypeFoldable<'tcx> for Scope
sourcefn try_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
_: &mut F
) -> Result<Scope, F::Error>
fn try_fold_with<F: FallibleTypeFolder<'tcx>>(
self,
_: &mut F
) -> Result<Scope, F::Error>
sourcefn fold_with<F: TypeFolder<'tcx>>(self, folder: &mut F) -> Self
fn fold_with<F: TypeFolder<'tcx>>(self, folder: &mut F) -> Self
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 Scope
impl<'tcx> TypeVisitable<'tcx> for Scope
sourcefn visit_with<F: TypeVisitor<'tcx>>(&self, _: &mut F) -> ControlFlow<F::BreakTy>
fn visit_with<F: TypeVisitor<'tcx>>(&self, _: &mut F) -> ControlFlow<F::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 Copy for Scope
impl Eq for Scope
impl StructuralEq for Scope
impl StructuralPartialEq for Scope
Auto Trait Implementations
impl RefUnwindSafe for Scope
impl Send for Scope
impl Sync for Scope
impl Unpin for Scope
impl UnwindSafe for Scope
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<Ctxt, T> DepNodeParams<Ctxt> for Twhere
Ctxt: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
impl<Ctxt, T> DepNodeParams<Ctxt> for Twhere
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
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>
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 moresourceimpl<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>>::Outputwhere
I: Iterator<Item = T>,
F: FnOnce(&[T]) -> R,
sourceimpl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
sourceimpl<CTX, T> Value<CTX> for Twhere
CTX: DepContext,
impl<CTX, T> Value<CTX> for Twhere
CTX: DepContext,
default fn from_cycle_error(tcx: CTX) -> T
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: 8 bytes