Struct rustc_hir_analysis::check::region::RegionResolutionVisitor

struct RegionResolutionVisitor<'tcx> {
    tcx: TyCtxt<'tcx>,
    expr_and_pat_count: usize,
    pessimistic_yield: bool,
    fixup_scopes: Vec<Scope>,
    scope_tree: ScopeTree,
    cx: Context,
    terminating_scopes: FxHashSet<ItemLocalId>,
}

Fields

tcx: TyCtxt<'tcx>

expr_and_pat_count: usize

pessimistic_yield: bool

fixup_scopes: Vec<Scope>

scope_tree: ScopeTree

cx: Context

terminating_scopes: FxHashSet<ItemLocalId>

terminating_scopes is a set containing the ids of each statement, or conditional/repeating expression. These scopes are calling “terminating scopes” because, when attempting to find the scope of a temporary, by default we search up the enclosing scopes until we encounter the terminating scope. A conditional/repeating expression is one which is not guaranteed to execute exactly once upon entering the parent scope. This could be because the expression only executes conditionally, such as the expression b in a && b, or because the expression may execute many times, such as a loop body. The reason that we distinguish such expressions is that, upon exiting the parent scope, we cannot statically know how many times the expression executed, and thus if the expression creates temporaries we cannot know statically how many such temporaries we would have to cleanup. Therefore, we ensure that the temporaries never outlast the conditional/repeating expression, preventing the need for dynamic checks and/or arbitrary amounts of stack space. Terminating scopes end up being contained in a DestructionScope that contains the destructor’s execution.

Implementations

impl<'tcx> RegionResolutionVisitor<'tcx>

fn record_child_scope(&mut self, child_scope: Scope) -> ScopeDepth

Records the current parent (if any) as the parent of child_scope. Returns the depth of child_scope.

fn enter_scope(&mut self, child_scope: Scope)

Records the current parent (if any) as the parent of child_scope, and sets child_scope as the new current parent.

fn enter_node_scope_with_dtor(&mut self, id: ItemLocalId)

Trait Implementations

impl<'tcx> Visitor<'tcx> for RegionResolutionVisitor<'tcx>

fn visit_block(&mut self, b: &'tcx Block<'tcx>)

fn visit_body(&mut self, body: &'tcx Body<'tcx>)

fn visit_arm(&mut self, a: &'tcx Arm<'tcx>)

fn visit_pat(&mut self, p: &'tcx Pat<'tcx>)

fn visit_stmt(&mut self, s: &'tcx Stmt<'tcx>)

fn visit_expr(&mut self, ex: &'tcx Expr<'tcx>)

fn visit_local(&mut self, l: &'tcx Local<'tcx>)

type Map = <Self::NestedFilter as NestedFilter<'v>>::Map

type NestedFilter = None

Override this type to control which nested HIR are visited; see NestedFilter for details. If you override this type, you must also override nested_visit_map.

fn nested_visit_map(&mut self) -> Self::Map

If type NestedFilter is set to visit nested items, this method must also be overridden to provide a map to retrieve nested items.

fn visit_nested_item(&mut self, id: ItemId)

Invoked when a nested item is encountered. By default, when 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.

fn visit_nested_trait_item(&mut self, id: TraitItemId)

Like visit_nested_item(), but for trait items. See visit_nested_item() for advice on when to override this method.

fn visit_nested_impl_item(&mut self, id: ImplItemId)

Like visit_nested_item(), but for impl items. See visit_nested_item() for advice on when to override this method.

fn visit_nested_foreign_item(&mut self, id: ForeignItemId)

Like visit_nested_item(), but for foreign items. See visit_nested_item() for advice on when to override this method.

fn visit_nested_body(&mut self, id: BodyId)

Invoked to visit the body of a function, method or closure. Like visit_nested_item, does nothing by default unless you override Self::NestedFilter.

fn visit_param(&mut self, param: &'v Param<'v>)

fn visit_item(&mut self, i: &'v Item<'v>)

Visits the top-level item and (optionally) nested items / impl items. See visit_nested_item for details.

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_foreign_item(&mut self, i: &'v ForeignItem<'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_ty(&mut self, t: &'v Ty<'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_generics(&mut self, g: &'v Generics<'v>)

fn visit_where_predicate(&mut self, predicate: &'v WherePredicate<'v>)

fn visit_fn_ret_ty(&mut self, ret_ty: &'v FnRetTy<'v>)

fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>)

fn visit_fn(
    &mut self,
    fk: FnKind<'v>,
    fd: &'v FnDecl<'v>,
    b: BodyId,
    _: Span,
    id: HirId
)

fn visit_use(
    &mut self,
    path: &'v Path<'v, SmallVec<[Res<HirId>; 3]>>,
    hir_id: HirId
)

fn visit_trait_item(&mut self, ti: &'v TraitItem<'v>)

fn visit_trait_item_ref(&mut self, ii: &'v TraitItemRef)

fn visit_impl_item(&mut self, ii: &'v ImplItem<'v>)

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_param_bound(&mut self, bounds: &'v GenericBound<'v>)

fn visit_poly_trait_ref(&mut self, t: &'v PolyTraitRef<'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_lifetime(&mut self, lifetime: &'v Lifetime)

fn visit_qpath(&mut self, qpath: &'v QPath<'v>, id: HirId, _span: Span)

fn visit_path(&mut self, path: &Path<'v, Res<HirId>>, _id: HirId)

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)

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: 376 bytes