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§
source§impl 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§
source§impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for Scope
impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for Scope
fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher )
source§impl Ord for Scope
impl Ord for Scope
source§impl PartialEq<Scope> for Scope
impl PartialEq<Scope> for Scope
source§impl PartialOrd<Scope> for Scope
impl PartialOrd<Scope> for Scope
1.0.0 · source§fn le(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read moresource§impl<'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
source§impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Scope
impl<'tcx> TypeFoldable<TyCtxt<'tcx>> for Scope
source§fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>(
self,
_: &mut F
) -> Result<Self, F::Error>
fn try_fold_with<F: FallibleTypeFolder<TyCtxt<'tcx>>>( self, _: &mut F ) -> Result<Self, F::Error>
source§impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Scope
impl<'tcx> TypeVisitable<TyCtxt<'tcx>> for Scope
source§fn visit_with<F: TypeVisitor<TyCtxt<'tcx>>>(
&self,
_: &mut F
) -> ControlFlow<F::BreakTy>
fn visit_with<F: TypeVisitor<TyCtxt<'tcx>>>( &self, _: &mut F ) -> ControlFlow<F::BreakTy>
impl 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§
source§impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
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]
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
source§impl<T, R> CollectAndApply<T, R> for T
impl<T, R> CollectAndApply<T, R> for T
source§impl<Tcx, T> DepNodeParams<Tcx> for Twhere
Tcx: DepContext,
T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
impl<Tcx, T> DepNodeParams<Tcx> for Twhere Tcx: DepContext, T: for<'a> HashStable<StableHashingContext<'a>> + Debug,
default fn fingerprint_style() -> FingerprintStyle
source§default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_fingerprint(&self, tcx: Tcx) -> Fingerprint
default fn to_debug_str(&self, _: Tcx) -> String
source§default fn recover(_: Tcx, _: &DepNode) -> Option<T>
default fn recover(_: Tcx, _: &DepNode) -> 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.source§impl<P> IntoQueryParam<P> for P
impl<P> IntoQueryParam<P> for P
fn into_query_param(self) -> P
source§impl<'tcx, T> IsSuggestable<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
impl<'tcx, T> IsSuggestable<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>> + TypeFoldable<TyCtxt<'tcx>>,
source§impl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
source§impl<'tcx, T> ToPredicate<'tcx, T> for T
impl<'tcx, T> ToPredicate<'tcx, T> for T
fn to_predicate(self, _tcx: TyCtxt<'tcx>) -> T
source§impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere
T: TypeVisitable<TyCtxt<'tcx>>,
impl<'tcx, T> TypeVisitableExt<'tcx> for Twhere T: TypeVisitable<TyCtxt<'tcx>>,
source§fn 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.source§fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
fn has_vars_bound_above(&self, binder: DebruijnIndex) -> bool
true
if this type has any regions that escape binder
(and
hence are not bound by it).source§fn has_escaping_bound_vars(&self) -> bool
fn has_escaping_bound_vars(&self) -> bool
true
if this type has regions that are not a part of the type.
For example, for<'a> fn(&'a i32)
return false
, while fn(&'a i32)
would return true
. The latter can occur when traversing through the
former. Read morefn has_type_flags(&self, flags: TypeFlags) -> bool
fn has_projections(&self) -> bool
fn has_inherent_projections(&self) -> bool
fn has_opaque_types(&self) -> bool
fn has_generators(&self) -> bool
fn references_error(&self) -> bool
fn error_reported(&self) -> Result<(), ErrorGuaranteed>
fn has_non_region_param(&self) -> bool
fn has_infer_regions(&self) -> bool
fn has_infer_types(&self) -> bool
fn has_non_region_infer(&self) -> bool
fn has_infer(&self) -> bool
fn has_placeholders(&self) -> bool
fn has_non_region_placeholders(&self) -> bool
fn has_param(&self) -> bool
source§fn has_free_regions(&self) -> bool
fn has_free_regions(&self) -> bool
fn has_erased_regions(&self) -> bool
source§fn has_erasable_regions(&self) -> bool
fn has_erasable_regions(&self) -> bool
source§fn is_global(&self) -> bool
fn is_global(&self) -> bool
source§fn has_late_bound_regions(&self) -> bool
fn has_late_bound_regions(&self) -> bool
source§fn has_non_region_late_bound(&self) -> bool
fn has_non_region_late_bound(&self) -> bool
source§fn has_late_bound_vars(&self) -> bool
fn has_late_bound_vars(&self) -> bool
source§fn still_further_specializable(&self) -> bool
fn still_further_specializable(&self) -> bool
impl
specialization.source§impl<Tcx, T> Value<Tcx> for Twhere
Tcx: DepContext,
impl<Tcx, T> Value<Tcx> for Twhere Tcx: DepContext,
default fn from_cycle_error( tcx: Tcx, cycle: &[QueryInfo], _guar: ErrorGuaranteed ) -> 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: 8 bytes