Struct rustc_resolve::late::lifetimes::LifetimeContext
source · pub(crate) struct LifetimeContext<'a, 'tcx> {
pub(crate) tcx: TyCtxt<'tcx>,
map: &'a mut NamedRegionMap,
scope: &'a Scope<'a>,
trait_definition_only: bool,
}
Fields
tcx: TyCtxt<'tcx>
map: &'a mut NamedRegionMap
scope: &'a Scope<'a>
trait_definition_only: bool
Indicates that we only care about the definition of a trait. This should
be false if the Item
we are resolving lifetimes for is not a trait or
we eventually need lifetimes resolve for trait items.
Implementations
sourceimpl<'a, 'tcx> LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> LifetimeContext<'a, 'tcx>
sourcefn poly_trait_ref_binder_info(
&mut self
) -> (Vec<BoundVariableKind>, BinderScopeType)
fn poly_trait_ref_binder_info(
&mut self
) -> (Vec<BoundVariableKind>, BinderScopeType)
Returns the binders in scope and the type of Binder
that should be created for a poly trait ref.
sourceimpl<'a, 'tcx> LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> LifetimeContext<'a, 'tcx>
fn with<F>(&mut self, wrap_scope: Scope<'_>, f: F)where
F: for<'b> FnOnce(&mut LifetimeContext<'b, 'tcx>),
sourcefn visit_early_late<F>(
&mut self,
hir_id: HirId,
generics: &'tcx Generics<'tcx>,
walk: F
)where
F: for<'b, 'c> FnOnce(&'b mut LifetimeContext<'c, 'tcx>),
fn visit_early_late<F>(
&mut self,
hir_id: HirId,
generics: &'tcx Generics<'tcx>,
walk: F
)where
F: for<'b, 'c> FnOnce(&'b mut LifetimeContext<'c, 'tcx>),
Visits self by adding a scope and handling recursive walk over the contents with walk
.
Handles visiting fns and methods. These are a bit complicated because we must distinguish early- vs late-bound lifetime parameters. We do this by checking which lifetimes appear within type bounds; those are early bound lifetimes, and the rest are late bound.
For example:
fn foo<’a,’b,’c,T:Trait<’b>>(…)
Here 'a
and 'c
are late bound but 'b
is early bound. Note that early- and late-bound
lifetimes may be interspersed together.
If early bound lifetimes are present, we separate them into their own list (and likewise
for late bound). They will be numbered sequentially, starting from the lowest index that is
already in scope (for a fn item, that will be 0, but for a method it might not be). Late
bound lifetimes are resolved by name and associated with a binder ID (binder_id
), so the
ordering is not important there.
fn resolve_lifetime_ref(
&mut self,
region_def_id: LocalDefId,
lifetime_ref: &'tcx Lifetime
)
fn visit_segment_args(
&mut self,
res: Res,
depth: usize,
generic_args: &'tcx GenericArgs<'tcx>
)
sourcefn supertrait_hrtb_lifetimes(
tcx: TyCtxt<'tcx>,
def_id: DefId,
assoc_name: Ident
) -> Option<Vec<BoundVariableKind>>
fn supertrait_hrtb_lifetimes(
tcx: TyCtxt<'tcx>,
def_id: DefId,
assoc_name: Ident
) -> Option<Vec<BoundVariableKind>>
Returns all the late-bound vars that come into scope from supertrait HRTBs, based on the associated type name and starting trait. For example, imagine we have
trait Foo<'a, 'b> {
type As;
}
trait Bar<'b>: for<'a> Foo<'a, 'b> {}
trait Bar: for<'b> Bar<'b> {}
In this case, if we wanted to the supertrait HRTB lifetimes for As
on
the starting trait Bar
, we would return Some(['b, 'a])
.
fn visit_fn_like_elision(
&mut self,
inputs: &'tcx [Ty<'tcx>],
output: Option<&'tcx Ty<'tcx>>,
in_closure: bool
)
fn resolve_object_lifetime_default(&mut self, lifetime_ref: &'tcx Lifetime)
fn insert_lifetime(&mut self, lifetime_ref: &'tcx Lifetime, def: Region)
sourcefn uninsert_lifetime_on_error(
&mut self,
lifetime_ref: &'tcx Lifetime,
bad_def: Region
)
fn uninsert_lifetime_on_error(
&mut self,
lifetime_ref: &'tcx Lifetime,
bad_def: Region
)
Sometimes we resolve a lifetime, but later find that it is an
error (esp. around impl trait). In that case, we remove the
entry into map.defs
so as not to confuse later code.
Trait Implementations
sourceimpl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx>
type NestedFilter = All
type NestedFilter = All
NestedFilter
for details. If you override this type, you
must also override nested_visit_map
. Read moresourcefn nested_visit_map(&mut self) -> Self::Map
fn nested_visit_map(&mut self) -> Self::Map
type NestedFilter
is set to visit nested items, this method
must also be overridden to provide a map to retrieve nested items. Read moresourcefn visit_nested_item(&mut self, _: ItemId)
fn visit_nested_item(&mut self, _: ItemId)
Self::NestedFilter
is nested_filter::None
, this method does
nothing. You probably don’t want to override this method –
instead, override Self::NestedFilter
or use the “shallow” or
“deep” visit patterns described on
itemlikevisit::ItemLikeVisitor
. The only reason to override
this method is if you want a nested pattern but cannot supply a
Map
; see nested_visit_map
for advice. Read morefn visit_trait_item_ref(&mut self, ii: &'tcx TraitItemRef)
sourcefn visit_nested_body(&mut self, body: BodyId)
fn visit_nested_body(&mut self, body: BodyId)
visit_nested_item
, does nothing by default unless you override
Self::NestedFilter
. Read morefn visit_expr(&mut self, e: &'tcx Expr<'tcx>)
sourcefn visit_item(&mut self, item: &'tcx Item<'tcx>)
fn visit_item(&mut self, item: &'tcx Item<'tcx>)
visit_nested_item
for details. Read morefn visit_foreign_item(&mut self, item: &'tcx ForeignItem<'tcx>)
fn visit_ty(&mut self, ty: &'tcx Ty<'tcx>)
fn visit_trait_item(&mut self, trait_item: &'tcx TraitItem<'tcx>)
fn visit_impl_item(&mut self, impl_item: &'tcx ImplItem<'tcx>)
fn visit_lifetime(&mut self, lifetime_ref: &'tcx Lifetime)
fn visit_path(&mut self, path: &'tcx Path<'tcx>, _: HirId)
fn visit_fn(
&mut self,
fk: FnKind<'tcx>,
fd: &'tcx FnDecl<'tcx>,
body_id: BodyId,
_: Span,
_: HirId
)
fn visit_generics(&mut self, generics: &'tcx Generics<'tcx>)
fn visit_param_bound(&mut self, bound: &'tcx GenericBound<'tcx>)
fn visit_poly_trait_ref(&mut self, trait_ref: &'tcx PolyTraitRef<'tcx>)
type Map = <Self::NestedFilter as NestedFilter<'v>>::Map
sourcefn visit_nested_trait_item(&mut self, id: TraitItemId)
fn visit_nested_trait_item(&mut self, id: TraitItemId)
visit_nested_item()
, but for trait items. See
visit_nested_item()
for advice on when to override this
method. Read moresourcefn visit_nested_impl_item(&mut self, id: ImplItemId)
fn visit_nested_impl_item(&mut self, id: ImplItemId)
visit_nested_item()
, but for impl items. See
visit_nested_item()
for advice on when to override this
method. Read moresourcefn visit_nested_foreign_item(&mut self, id: ForeignItemId)
fn visit_nested_foreign_item(&mut self, id: ForeignItemId)
visit_nested_item()
, but for foreign items. See
visit_nested_item()
for advice on when to override this
method. Read morefn visit_param(&mut self, param: &'v Param<'v>)
fn visit_body(&mut self, b: &'v Body<'v>)
fn visit_id(&mut self, _hir_id: HirId)
fn visit_name(&mut self, _name: Symbol)
fn visit_ident(&mut self, ident: Ident)
fn visit_mod(&mut self, m: &'v Mod<'v>, _s: Span, n: HirId)
fn visit_local(&mut self, l: &'v Local<'v>)
fn visit_block(&mut self, b: &'v Block<'v>)
fn visit_stmt(&mut self, s: &'v Stmt<'v>)
fn visit_arm(&mut self, a: &'v Arm<'v>)
fn visit_pat(&mut self, p: &'v Pat<'v>)
fn visit_pat_field(&mut self, f: &'v PatField<'v>)
fn visit_array_length(&mut self, len: &'v ArrayLen)
fn visit_anon_const(&mut self, c: &'v AnonConst)
fn visit_let_expr(&mut self, lex: &'v Let<'v>)
fn visit_expr_field(&mut self, field: &'v ExprField<'v>)
fn visit_generic_param(&mut self, p: &'v GenericParam<'v>)
fn visit_const_param_default(&mut self, _param: HirId, ct: &'v AnonConst)
fn visit_where_predicate(&mut self, predicate: &'v WherePredicate<'v>)
fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>)
fn visit_use(&mut self, path: &'v Path<'v>, hir_id: HirId)
fn visit_foreign_item_ref(&mut self, ii: &'v ForeignItemRef)
fn visit_impl_item_ref(&mut self, ii: &'v ImplItemRef)
fn visit_trait_ref(&mut self, t: &'v TraitRef<'v>)
fn visit_variant_data(&mut self, s: &'v VariantData<'v>)
fn visit_field_def(&mut self, s: &'v FieldDef<'v>)
fn visit_enum_def(&mut self, enum_definition: &'v EnumDef<'v>, item_id: HirId)
fn visit_variant(&mut self, v: &'v Variant<'v>)
fn visit_label(&mut self, label: &'v Label)
fn visit_infer(&mut self, inf: &'v InferArg)
fn visit_generic_arg(&mut self, generic_arg: &'v GenericArg<'v>)
fn visit_qpath(&mut self, qpath: &'v QPath<'v>, id: HirId, _span: Span)
fn visit_path_segment(&mut self, path_segment: &'v PathSegment<'v>)
fn visit_generic_args(&mut self, generic_args: &'v GenericArgs<'v>)
fn visit_assoc_type_binding(&mut self, type_binding: &'v TypeBinding<'v>)
fn visit_attribute(&mut self, _attr: &'v Attribute)
fn visit_associated_item_kind(&mut self, kind: &'v AssocItemKind)
fn visit_defaultness(&mut self, defaultness: &'v Defaultness)
fn visit_inline_asm(&mut self, asm: &'v InlineAsm<'v>, id: HirId)
Auto Trait Implementations
impl<'a, 'tcx> !RefUnwindSafe for LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> !Send for LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> !Sync for LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> Unpin for LifetimeContext<'a, 'tcx>
impl<'a, 'tcx> !UnwindSafe for LifetimeContext<'a, 'tcx>
Blanket Implementations
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
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