Struct ScopeTree

pub struct ScopeTree {
    pub root_body: Option<HirId>,
    pub parent_map: FxIndexMap<Scope, Scope>,
    var_map: FxIndexMap<ItemLocalId, Scope>,
    pub rvalue_candidates: HirIdMap<RvalueCandidate>,
    pub backwards_incompatible_scope: UnordMap<ItemLocalId, Scope>,
}

The region scope tree encodes information about region relationships.

Fields

root_body: Option<HirId>

If not empty, this body is the root of this region hierarchy.

parent_map: FxIndexMap<Scope, Scope>

Maps from a scope ID to the enclosing scope id; this is usually corresponding to the lexical nesting, though in the case of closures the parent scope is the innermost conditional expression or repeating block. (Note that the enclosing scope ID for the block associated with a closure is the closure itself.)

var_map: FxIndexMap<ItemLocalId, Scope>

Maps from a variable or binding ID to the block in which that variable is declared.

rvalue_candidates: HirIdMap<RvalueCandidate>

Identifies expressions which, if captured into a temporary, ought to have a temporary whose lifetime extends to the end of the enclosing block, and not the enclosing statement. Expressions that are not present in this table are not rvalue candidates. The set of rvalue candidates is computed during type check based on a traversal of the AST.

backwards_incompatible_scope: UnordMap<ItemLocalId, Scope>

Backwards incompatible scoping that will be introduced in future editions. This information is used later for linting to identify locals and temporary values that will receive backwards-incompatible drop orders.

Implementations

impl ScopeTree

pub fn record_scope_parent(&mut self, child: Scope, parent: Option<Scope>)

pub fn record_var_scope(&mut self, var: ItemLocalId, lifetime: Scope)

pub fn record_rvalue_candidate( &mut self, var: HirId, candidate: RvalueCandidate, )

pub fn opt_encl_scope(&self, id: Scope) -> Option<Scope>

Returns the narrowest scope that encloses id, if any.

pub fn var_scope(&self, var_id: ItemLocalId) -> Option<Scope>

Returns the lifetime of the local variable var_id, if any.

pub fn is_subscope_of(&self, subscope: Scope, superscope: Scope) -> bool

Returns true if subscope is equal to or is lexically nested inside superscope, and false otherwise.

Used by clippy.

Trait Implementations

impl<'tcx> ArenaAllocatable<'tcx> for ScopeTree

fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut Self

fn allocate_from_iter( arena: &'tcx Arena<'tcx>, iter: impl IntoIterator<Item = Self>, ) -> &'tcx mut [Self]

impl Debug for ScopeTree

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ScopeTree

fn default() -> ScopeTree

Returns the “default value” for a type.

impl<'__ctx> HashStable<StableHashingContext<'__ctx>> for ScopeTree

fn hash_stable( &self, __hcx: &mut StableHashingContext<'__ctx>, __hasher: &mut StableHasher, )

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: 208 bytes