1 //! HIR walker for walking the contents of nodes.
3 //! Here are the three available patterns for the visitor strategy,
4 //! in roughly the order of desirability:
6 //! 1. **Shallow visit**: Get a simple callback for every item (or item-like thing) in the HIR.
7 //! - Example: find all items with a `#[foo]` attribute on them.
8 //! - How: Use the `hir_crate_items` or `hir_module_items` query to traverse over item-like ids
9 //! (ItemId, TraitItemId, etc.) and use tcx.def_kind and `tcx.hir().item*(id)` to filter and
10 //! access actual item-like thing, respectively.
11 //! - Pro: Efficient; just walks the lists of item ids and gives users control whether to access
12 //! the hir_owners themselves or not.
13 //! - Con: Don't get information about nesting
14 //! - Con: Don't have methods for specific bits of HIR, like "on
15 //! every expr, do this".
16 //! 2. **Deep visit**: Want to scan for specific kinds of HIR nodes within
17 //! an item, but don't care about how item-like things are nested
18 //! within one another.
19 //! - Example: Examine each expression to look for its type and do some check or other.
20 //! - How: Implement `intravisit::Visitor` and override the `NestedFilter` type to
21 //! `nested_filter::OnlyBodies` (and implement `nested_visit_map`), and use
22 //! `tcx.hir().deep_visit_all_item_likes(&mut visitor)`. Within your
23 //! `intravisit::Visitor` impl, implement methods like `visit_expr()` (don't forget to invoke
24 //! `intravisit::walk_expr()` to keep walking the subparts).
25 //! - Pro: Visitor methods for any kind of HIR node, not just item-like things.
26 //! - Pro: Integrates well into dependency tracking.
27 //! - Con: Don't get information about nesting between items
28 //! 3. **Nested visit**: Want to visit the whole HIR and you care about the nesting between
30 //! - Example: Lifetime resolution, which wants to bring lifetimes declared on the
31 //! impl into scope while visiting the impl-items, and then back out again.
32 //! - How: Implement `intravisit::Visitor` and override the `NestedFilter` type to
33 //! `nested_filter::All` (and implement `nested_visit_map`). Walk your crate with
34 //! `tcx.hir().walk_toplevel_module(visitor)` invoked on `tcx.hir().krate()`.
35 //! - Pro: Visitor methods for any kind of HIR node, not just item-like things.
36 //! - Pro: Preserves nesting information
37 //! - Con: Does not integrate well into dependency tracking.
39 //! If you have decided to use this visitor, here are some general
40 //! notes on how to do so:
42 //! Each overridden visit method has full control over what
43 //! happens with its node, it can do its own traversal of the node's children,
44 //! call `intravisit::walk_*` to apply the default traversal algorithm, or prevent
45 //! deeper traversal by doing nothing.
47 //! When visiting the HIR, the contents of nested items are NOT visited
48 //! by default. This is different from the AST visitor, which does a deep walk.
49 //! Hence this module is called `intravisit`; see the method `visit_nested_item`
52 //! Note: it is an important invariant that the default visitor walks
53 //! the body of a function in "execution order" - more concretely, if
54 //! we consider the reverse post-order (RPO) of the CFG implied by the HIR,
55 //! then a pre-order traversal of the HIR is consistent with the CFG RPO
56 //! on the *initial CFG point* of each HIR node, while a post-order traversal
57 //! of the HIR is consistent with the CFG RPO on each *final CFG point* of
60 //! One thing that follows is that if HIR node A always starts/ends executing
61 //! before HIR node B, then A appears in traversal pre/postorder before B,
62 //! respectively. (This follows from RPO respecting CFG domination).
64 //! This order consistency is required in a few places in rustc, for
65 //! example generator inference, and possibly also HIR borrowck.
68 use crate::itemlikevisit
::ParItemLikeVisitor
;
69 use rustc_ast
::walk_list
;
70 use rustc_ast
::{Attribute, Label}
;
71 use rustc_span
::symbol
::{Ident, Symbol}
;
74 pub trait IntoVisitor
<'hir
> {
75 type Visitor
: Visitor
<'hir
>;
76 fn into_visitor(&self) -> Self::Visitor
;
79 pub struct ParDeepVisitor
<V
>(pub V
);
81 impl<'hir
, V
> ParItemLikeVisitor
<'hir
> for ParDeepVisitor
<V
>
85 fn visit_item(&self, item
: &'hir Item
<'hir
>) {
86 self.0.into_visitor
().visit_item(item
);
89 fn visit_trait_item(&self, trait_item
: &'hir TraitItem
<'hir
>) {
90 self.0.into_visitor
().visit_trait_item(trait_item
);
93 fn visit_impl_item(&self, impl_item
: &'hir ImplItem
<'hir
>) {
94 self.0.into_visitor
().visit_impl_item(impl_item
);
97 fn visit_foreign_item(&self, foreign_item
: &'hir ForeignItem
<'hir
>) {
98 self.0.into_visitor
().visit_foreign_item(foreign_item
);
102 #[derive(Copy, Clone, Debug)]
103 pub enum FnKind
<'a
> {
104 /// `#[xxx] pub async/const/extern "Abi" fn foo()`
105 ItemFn(Ident
, &'a Generics
<'a
>, FnHeader
),
108 Method(Ident
, &'a FnSig
<'a
>),
114 impl<'a
> FnKind
<'a
> {
115 pub fn header(&self) -> Option
<&FnHeader
> {
117 FnKind
::ItemFn(_
, _
, ref header
) => Some(header
),
118 FnKind
::Method(_
, ref sig
) => Some(&sig
.header
),
119 FnKind
::Closure
=> None
,
123 pub fn constness(self) -> Constness
{
124 self.header().map_or(Constness
::NotConst
, |header
| header
.constness
)
127 pub fn asyncness(self) -> IsAsync
{
128 self.header().map_or(IsAsync
::NotAsync
, |header
| header
.asyncness
)
132 /// An abstract representation of the HIR `rustc_middle::hir::map::Map`.
133 pub trait Map
<'hir
> {
134 /// Retrieves the `Node` corresponding to `id`, returning `None` if cannot be found.
135 fn find(&self, hir_id
: HirId
) -> Option
<Node
<'hir
>>;
136 fn body(&self, id
: BodyId
) -> &'hir Body
<'hir
>;
137 fn item(&self, id
: ItemId
) -> &'hir Item
<'hir
>;
138 fn trait_item(&self, id
: TraitItemId
) -> &'hir TraitItem
<'hir
>;
139 fn impl_item(&self, id
: ImplItemId
) -> &'hir ImplItem
<'hir
>;
140 fn foreign_item(&self, id
: ForeignItemId
) -> &'hir ForeignItem
<'hir
>;
143 // Used when no map is actually available, forcing manual implementation of nested visitors.
144 impl<'hir
> Map
<'hir
> for ! {
145 fn find(&self, _
: HirId
) -> Option
<Node
<'hir
>> {
148 fn body(&self, _
: BodyId
) -> &'hir Body
<'hir
> {
151 fn item(&self, _
: ItemId
) -> &'hir Item
<'hir
> {
154 fn trait_item(&self, _
: TraitItemId
) -> &'hir TraitItem
<'hir
> {
157 fn impl_item(&self, _
: ImplItemId
) -> &'hir ImplItem
<'hir
> {
160 fn foreign_item(&self, _
: ForeignItemId
) -> &'hir ForeignItem
<'hir
> {
165 pub mod nested_filter
{
168 /// Specifies what nested things a visitor wants to visit. By "nested
169 /// things", we are referring to bits of HIR that are not directly embedded
170 /// within one another but rather indirectly, through a table in the crate.
171 /// This is done to control dependencies during incremental compilation: the
172 /// non-inline bits of HIR can be tracked and hashed separately.
174 /// The most common choice is `OnlyBodies`, which will cause the visitor to
175 /// visit fn bodies for fns that it encounters, and closure bodies, but
176 /// skip over nested item-like things.
178 /// See the comments on `ItemLikeVisitor` for more details on the overall
180 pub trait NestedFilter
<'hir
> {
183 /// Whether the visitor visits nested "item-like" things.
184 /// E.g., item, impl-item.
186 /// Whether the visitor visits "intra item-like" things.
187 /// E.g., function body, closure, `AnonConst`
191 /// Do not visit any nested things. When you add a new
192 /// "non-nested" thing, you will want to audit such uses to see if
193 /// they remain valid.
195 /// Use this if you are only walking some particular kind of tree
196 /// (i.e., a type, or fn signature) and you don't want to thread a
199 impl NestedFilter
<'_
> for None
{
201 const INTER
: bool
= false;
202 const INTRA
: bool
= false;
206 use nested_filter
::NestedFilter
;
208 /// Each method of the Visitor trait is a hook to be potentially
209 /// overridden. Each method's default implementation recursively visits
210 /// the substructure of the input via the corresponding `walk` method;
211 /// e.g., the `visit_mod` method by default calls `intravisit::walk_mod`.
213 /// Note that this visitor does NOT visit nested items by default
214 /// (this is why the module is called `intravisit`, to distinguish it
215 /// from the AST's `visit` module, which acts differently). If you
216 /// simply want to visit all items in the crate in some order, you
217 /// should call `Crate::visit_all_items`. Otherwise, see the comment
218 /// on `visit_nested_item` for details on how to visit nested items.
220 /// If you want to ensure that your code handles every variant
221 /// explicitly, you need to override each method. (And you also need
222 /// to monitor future changes to `Visitor` in case a new method with a
223 /// new default implementation gets introduced.)
224 pub trait Visitor
<'v
>: Sized
{
225 // this type should not be overridden, it exists for convenient usage as `Self::Map`
226 type Map
: Map
<'v
> = <Self::NestedFilter
as NestedFilter
<'v
>>::Map
;
228 ///////////////////////////////////////////////////////////////////////////
231 /// Override this type to control which nested HIR are visited; see
232 /// [`NestedFilter`] for details. If you override this type, you
233 /// must also override [`nested_visit_map`](Self::nested_visit_map).
235 /// **If for some reason you want the nested behavior, but don't
236 /// have a `Map` at your disposal:** then override the
237 /// `visit_nested_XXX` methods. If a new `visit_nested_XXX` variant is
238 /// added in the future, it will cause a panic which can be detected
239 /// and fixed appropriately.
240 type NestedFilter
: NestedFilter
<'v
> = nested_filter
::None
;
242 /// If `type NestedFilter` is set to visit nested items, this method
243 /// must also be overridden to provide a map to retrieve nested items.
244 fn nested_visit_map(&mut self) -> Self::Map
{
246 "nested_visit_map must be implemented or consider using \
247 `type NestedFilter = nested_filter::None` (the default)"
251 /// Invoked when a nested item is encountered. By default, when
252 /// `Self::NestedFilter` is `nested_filter::None`, this method does
253 /// nothing. **You probably don't want to override this method** --
254 /// instead, override [`Self::NestedFilter`] or use the "shallow" or
255 /// "deep" visit patterns described on
256 /// `itemlikevisit::ItemLikeVisitor`. The only reason to override
257 /// this method is if you want a nested pattern but cannot supply a
258 /// [`Map`]; see `nested_visit_map` for advice.
259 fn visit_nested_item(&mut self, id
: ItemId
) {
260 if Self::NestedFilter
::INTER
{
261 let item
= self.nested_visit_map().item(id
);
262 self.visit_item(item
);
266 /// Like `visit_nested_item()`, but for trait items. See
267 /// `visit_nested_item()` for advice on when to override this
269 fn visit_nested_trait_item(&mut self, id
: TraitItemId
) {
270 if Self::NestedFilter
::INTER
{
271 let item
= self.nested_visit_map().trait_item(id
);
272 self.visit_trait_item(item
);
276 /// Like `visit_nested_item()`, but for impl items. See
277 /// `visit_nested_item()` for advice on when to override this
279 fn visit_nested_impl_item(&mut self, id
: ImplItemId
) {
280 if Self::NestedFilter
::INTER
{
281 let item
= self.nested_visit_map().impl_item(id
);
282 self.visit_impl_item(item
);
286 /// Like `visit_nested_item()`, but for foreign items. See
287 /// `visit_nested_item()` for advice on when to override this
289 fn visit_nested_foreign_item(&mut self, id
: ForeignItemId
) {
290 if Self::NestedFilter
::INTER
{
291 let item
= self.nested_visit_map().foreign_item(id
);
292 self.visit_foreign_item(item
);
296 /// Invoked to visit the body of a function, method or closure. Like
297 /// `visit_nested_item`, does nothing by default unless you override
298 /// `Self::NestedFilter`.
299 fn visit_nested_body(&mut self, id
: BodyId
) {
300 if Self::NestedFilter
::INTRA
{
301 let body
= self.nested_visit_map().body(id
);
302 self.visit_body(body
);
306 fn visit_param(&mut self, param
: &'v Param
<'v
>) {
307 walk_param(self, param
)
310 /// Visits the top-level item and (optionally) nested items / impl items. See
311 /// `visit_nested_item` for details.
312 fn visit_item(&mut self, i
: &'v Item
<'v
>) {
316 fn visit_body(&mut self, b
: &'v Body
<'v
>) {
320 ///////////////////////////////////////////////////////////////////////////
322 fn visit_id(&mut self, _hir_id
: HirId
) {
325 fn visit_name(&mut self, _span
: Span
, _name
: Symbol
) {
328 fn visit_ident(&mut self, ident
: Ident
) {
329 walk_ident(self, ident
)
331 fn visit_mod(&mut self, m
: &'v Mod
<'v
>, _s
: Span
, n
: HirId
) {
334 fn visit_foreign_item(&mut self, i
: &'v ForeignItem
<'v
>) {
335 walk_foreign_item(self, i
)
337 fn visit_local(&mut self, l
: &'v Local
<'v
>) {
340 fn visit_block(&mut self, b
: &'v Block
<'v
>) {
343 fn visit_stmt(&mut self, s
: &'v Stmt
<'v
>) {
346 fn visit_arm(&mut self, a
: &'v Arm
<'v
>) {
349 fn visit_pat(&mut self, p
: &'v Pat
<'v
>) {
352 fn visit_array_length(&mut self, len
: &'v ArrayLen
) {
353 walk_array_len(self, len
)
355 fn visit_anon_const(&mut self, c
: &'v AnonConst
) {
356 walk_anon_const(self, c
)
358 fn visit_expr(&mut self, ex
: &'v Expr
<'v
>) {
361 fn visit_let_expr(&mut self, lex
: &'v Let
<'v
>) {
362 walk_let_expr(self, lex
)
364 fn visit_ty(&mut self, t
: &'v Ty
<'v
>) {
367 fn visit_generic_param(&mut self, p
: &'v GenericParam
<'v
>) {
368 walk_generic_param(self, p
)
370 fn visit_const_param_default(&mut self, _param
: HirId
, ct
: &'v AnonConst
) {
371 walk_const_param_default(self, ct
)
373 fn visit_generics(&mut self, g
: &'v Generics
<'v
>) {
374 walk_generics(self, g
)
376 fn visit_where_predicate(&mut self, predicate
: &'v WherePredicate
<'v
>) {
377 walk_where_predicate(self, predicate
)
379 fn visit_fn_decl(&mut self, fd
: &'v FnDecl
<'v
>) {
380 walk_fn_decl(self, fd
)
382 fn visit_fn(&mut self, fk
: FnKind
<'v
>, fd
: &'v FnDecl
<'v
>, b
: BodyId
, s
: Span
, id
: HirId
) {
383 walk_fn(self, fk
, fd
, b
, s
, id
)
385 fn visit_use(&mut self, path
: &'v Path
<'v
>, hir_id
: HirId
) {
386 walk_use(self, path
, hir_id
)
388 fn visit_trait_item(&mut self, ti
: &'v TraitItem
<'v
>) {
389 walk_trait_item(self, ti
)
391 fn visit_trait_item_ref(&mut self, ii
: &'v TraitItemRef
) {
392 walk_trait_item_ref(self, ii
)
394 fn visit_impl_item(&mut self, ii
: &'v ImplItem
<'v
>) {
395 walk_impl_item(self, ii
)
397 fn visit_foreign_item_ref(&mut self, ii
: &'v ForeignItemRef
) {
398 walk_foreign_item_ref(self, ii
)
400 fn visit_impl_item_ref(&mut self, ii
: &'v ImplItemRef
) {
401 walk_impl_item_ref(self, ii
)
403 fn visit_trait_ref(&mut self, t
: &'v TraitRef
<'v
>) {
404 walk_trait_ref(self, t
)
406 fn visit_param_bound(&mut self, bounds
: &'v GenericBound
<'v
>) {
407 walk_param_bound(self, bounds
)
409 fn visit_poly_trait_ref(&mut self, t
: &'v PolyTraitRef
<'v
>, m
: TraitBoundModifier
) {
410 walk_poly_trait_ref(self, t
, m
)
412 fn visit_variant_data(
414 s
: &'v VariantData
<'v
>,
420 walk_struct_def(self, s
)
422 fn visit_field_def(&mut self, s
: &'v FieldDef
<'v
>) {
423 walk_field_def(self, s
)
427 enum_definition
: &'v EnumDef
<'v
>,
428 generics
: &'v Generics
<'v
>,
432 walk_enum_def(self, enum_definition
, generics
, item_id
)
434 fn visit_variant(&mut self, v
: &'v Variant
<'v
>, g
: &'v Generics
<'v
>, item_id
: HirId
) {
435 walk_variant(self, v
, g
, item_id
)
437 fn visit_label(&mut self, label
: &'v Label
) {
438 walk_label(self, label
)
440 fn visit_infer(&mut self, inf
: &'v InferArg
) {
443 fn visit_generic_arg(&mut self, generic_arg
: &'v GenericArg
<'v
>) {
445 GenericArg
::Lifetime(lt
) => self.visit_lifetime(lt
),
446 GenericArg
::Type(ty
) => self.visit_ty(ty
),
447 GenericArg
::Const(ct
) => self.visit_anon_const(&ct
.value
),
448 GenericArg
::Infer(inf
) => self.visit_infer(inf
),
451 fn visit_lifetime(&mut self, lifetime
: &'v Lifetime
) {
452 walk_lifetime(self, lifetime
)
454 fn visit_qpath(&mut self, qpath
: &'v QPath
<'v
>, id
: HirId
, span
: Span
) {
455 walk_qpath(self, qpath
, id
, span
)
457 fn visit_path(&mut self, path
: &'v Path
<'v
>, _id
: HirId
) {
458 walk_path(self, path
)
460 fn visit_path_segment(&mut self, path_span
: Span
, path_segment
: &'v PathSegment
<'v
>) {
461 walk_path_segment(self, path_span
, path_segment
)
463 fn visit_generic_args(&mut self, path_span
: Span
, generic_args
: &'v GenericArgs
<'v
>) {
464 walk_generic_args(self, path_span
, generic_args
)
466 fn visit_assoc_type_binding(&mut self, type_binding
: &'v TypeBinding
<'v
>) {
467 walk_assoc_type_binding(self, type_binding
)
469 fn visit_attribute(&mut self, _attr
: &'v Attribute
) {}
470 fn visit_associated_item_kind(&mut self, kind
: &'v AssocItemKind
) {
471 walk_associated_item_kind(self, kind
);
473 fn visit_defaultness(&mut self, defaultness
: &'v Defaultness
) {
474 walk_defaultness(self, defaultness
);
476 fn visit_inline_asm(&mut self, asm
: &'v InlineAsm
<'v
>, id
: HirId
) {
477 walk_inline_asm(self, asm
, id
);
481 pub fn walk_mod
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, module
: &'v Mod
<'v
>, mod_hir_id
: HirId
) {
482 visitor
.visit_id(mod_hir_id
);
483 for &item_id
in module
.item_ids
{
484 visitor
.visit_nested_item(item_id
);
488 pub fn walk_body
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, body
: &'v Body
<'v
>) {
489 walk_list
!(visitor
, visit_param
, body
.params
);
490 visitor
.visit_expr(&body
.value
);
493 pub fn walk_local
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, local
: &'v Local
<'v
>) {
494 // Intentionally visiting the expr first - the initialization expr
495 // dominates the local's definition.
496 walk_list
!(visitor
, visit_expr
, &local
.init
);
497 visitor
.visit_id(local
.hir_id
);
498 visitor
.visit_pat(&local
.pat
);
499 walk_list
!(visitor
, visit_ty
, &local
.ty
);
502 pub fn walk_ident
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, ident
: Ident
) {
503 visitor
.visit_name(ident
.span
, ident
.name
);
506 pub fn walk_label
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, label
: &'v Label
) {
507 visitor
.visit_ident(label
.ident
);
510 pub fn walk_lifetime
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, lifetime
: &'v Lifetime
) {
511 visitor
.visit_id(lifetime
.hir_id
);
512 match lifetime
.name
{
513 LifetimeName
::Param(_
, ParamName
::Plain(ident
)) => {
514 visitor
.visit_ident(ident
);
516 LifetimeName
::Param(_
, ParamName
::Fresh
)
517 | LifetimeName
::Param(_
, ParamName
::Error
)
518 | LifetimeName
::Static
519 | LifetimeName
::Error
520 | LifetimeName
::Implicit
521 | LifetimeName
::ImplicitObjectLifetimeDefault
522 | LifetimeName
::Underscore
=> {}
526 pub fn walk_poly_trait_ref
<'v
, V
: Visitor
<'v
>>(
528 trait_ref
: &'v PolyTraitRef
<'v
>,
529 _modifier
: TraitBoundModifier
,
531 walk_list
!(visitor
, visit_generic_param
, trait_ref
.bound_generic_params
);
532 visitor
.visit_trait_ref(&trait_ref
.trait_ref
);
535 pub fn walk_trait_ref
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, trait_ref
: &'v TraitRef
<'v
>) {
536 visitor
.visit_id(trait_ref
.hir_ref_id
);
537 visitor
.visit_path(&trait_ref
.path
, trait_ref
.hir_ref_id
)
540 pub fn walk_param
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, param
: &'v Param
<'v
>) {
541 visitor
.visit_id(param
.hir_id
);
542 visitor
.visit_pat(¶m
.pat
);
545 pub fn walk_item
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, item
: &'v Item
<'v
>) {
546 visitor
.visit_ident(item
.ident
);
548 ItemKind
::ExternCrate(orig_name
) => {
549 visitor
.visit_id(item
.hir_id());
550 if let Some(orig_name
) = orig_name
{
551 visitor
.visit_name(item
.span
, orig_name
);
554 ItemKind
::Use(ref path
, _
) => {
555 visitor
.visit_use(path
, item
.hir_id());
557 ItemKind
::Static(ref typ
, _
, body
) | ItemKind
::Const(ref typ
, body
) => {
558 visitor
.visit_id(item
.hir_id());
559 visitor
.visit_ty(typ
);
560 visitor
.visit_nested_body(body
);
562 ItemKind
::Fn(ref sig
, ref generics
, body_id
) => visitor
.visit_fn(
563 FnKind
::ItemFn(item
.ident
, generics
, sig
.header
),
569 ItemKind
::Macro(..) => {
570 visitor
.visit_id(item
.hir_id());
572 ItemKind
::Mod(ref module
) => {
573 // `visit_mod()` takes care of visiting the `Item`'s `HirId`.
574 visitor
.visit_mod(module
, item
.span
, item
.hir_id())
576 ItemKind
::ForeignMod { abi: _, items }
=> {
577 visitor
.visit_id(item
.hir_id());
578 walk_list
!(visitor
, visit_foreign_item_ref
, items
);
580 ItemKind
::GlobalAsm(asm
) => {
581 visitor
.visit_id(item
.hir_id());
582 visitor
.visit_inline_asm(asm
, item
.hir_id());
584 ItemKind
::TyAlias(ref ty
, ref generics
) => {
585 visitor
.visit_id(item
.hir_id());
586 visitor
.visit_ty(ty
);
587 visitor
.visit_generics(generics
)
589 ItemKind
::OpaqueTy(OpaqueTy { ref generics, bounds, .. }
) => {
590 visitor
.visit_id(item
.hir_id());
591 walk_generics(visitor
, generics
);
592 walk_list
!(visitor
, visit_param_bound
, bounds
);
594 ItemKind
::Enum(ref enum_definition
, ref generics
) => {
595 visitor
.visit_generics(generics
);
596 // `visit_enum_def()` takes care of visiting the `Item`'s `HirId`.
597 visitor
.visit_enum_def(enum_definition
, generics
, item
.hir_id(), item
.span
)
599 ItemKind
::Impl(Impl
{
610 visitor
.visit_id(item
.hir_id());
611 visitor
.visit_generics(generics
);
612 walk_list
!(visitor
, visit_trait_ref
, of_trait
);
613 visitor
.visit_ty(self_ty
);
614 walk_list
!(visitor
, visit_impl_item_ref
, *items
);
616 ItemKind
::Struct(ref struct_definition
, ref generics
)
617 | ItemKind
::Union(ref struct_definition
, ref generics
) => {
618 visitor
.visit_generics(generics
);
619 visitor
.visit_id(item
.hir_id());
620 visitor
.visit_variant_data(
628 ItemKind
::Trait(.., ref generics
, bounds
, trait_item_refs
) => {
629 visitor
.visit_id(item
.hir_id());
630 visitor
.visit_generics(generics
);
631 walk_list
!(visitor
, visit_param_bound
, bounds
);
632 walk_list
!(visitor
, visit_trait_item_ref
, trait_item_refs
);
634 ItemKind
::TraitAlias(ref generics
, bounds
) => {
635 visitor
.visit_id(item
.hir_id());
636 visitor
.visit_generics(generics
);
637 walk_list
!(visitor
, visit_param_bound
, bounds
);
642 pub fn walk_inline_asm
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, asm
: &'v InlineAsm
<'v
>, id
: HirId
) {
643 for (op
, op_sp
) in asm
.operands
{
645 InlineAsmOperand
::In { expr, .. }
| InlineAsmOperand
::InOut { expr, .. }
=> {
646 visitor
.visit_expr(expr
)
648 InlineAsmOperand
::Out { expr, .. }
=> {
649 if let Some(expr
) = expr
{
650 visitor
.visit_expr(expr
);
653 InlineAsmOperand
::SplitInOut { in_expr, out_expr, .. }
=> {
654 visitor
.visit_expr(in_expr
);
655 if let Some(out_expr
) = out_expr
{
656 visitor
.visit_expr(out_expr
);
659 InlineAsmOperand
::Const { anon_const, .. }
660 | InlineAsmOperand
::SymFn { anon_const, .. }
=> visitor
.visit_anon_const(anon_const
),
661 InlineAsmOperand
::SymStatic { path, .. }
=> visitor
.visit_qpath(path
, id
, *op_sp
),
666 pub fn walk_use
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, path
: &'v Path
<'v
>, hir_id
: HirId
) {
667 visitor
.visit_id(hir_id
);
668 visitor
.visit_path(path
, hir_id
);
671 pub fn walk_enum_def
<'v
, V
: Visitor
<'v
>>(
673 enum_definition
: &'v EnumDef
<'v
>,
674 generics
: &'v Generics
<'v
>,
677 visitor
.visit_id(item_id
);
678 walk_list
!(visitor
, visit_variant
, enum_definition
.variants
, generics
, item_id
);
681 pub fn walk_variant
<'v
, V
: Visitor
<'v
>>(
683 variant
: &'v Variant
<'v
>,
684 generics
: &'v Generics
<'v
>,
685 parent_item_id
: HirId
,
687 visitor
.visit_ident(variant
.ident
);
688 visitor
.visit_id(variant
.id
);
689 visitor
.visit_variant_data(
696 walk_list
!(visitor
, visit_anon_const
, &variant
.disr_expr
);
699 pub fn walk_ty
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, typ
: &'v Ty
<'v
>) {
700 visitor
.visit_id(typ
.hir_id
);
703 TyKind
::Slice(ref ty
) => visitor
.visit_ty(ty
),
704 TyKind
::Ptr(ref mutable_type
) => visitor
.visit_ty(&mutable_type
.ty
),
705 TyKind
::Rptr(ref lifetime
, ref mutable_type
) => {
706 visitor
.visit_lifetime(lifetime
);
707 visitor
.visit_ty(&mutable_type
.ty
)
710 TyKind
::Tup(tuple_element_types
) => {
711 walk_list
!(visitor
, visit_ty
, tuple_element_types
);
713 TyKind
::BareFn(ref function_declaration
) => {
714 walk_list
!(visitor
, visit_generic_param
, function_declaration
.generic_params
);
715 visitor
.visit_fn_decl(&function_declaration
.decl
);
717 TyKind
::Path(ref qpath
) => {
718 visitor
.visit_qpath(qpath
, typ
.hir_id
, typ
.span
);
720 TyKind
::OpaqueDef(item_id
, lifetimes
) => {
721 visitor
.visit_nested_item(item_id
);
722 walk_list
!(visitor
, visit_generic_arg
, lifetimes
);
724 TyKind
::Array(ref ty
, ref length
) => {
725 visitor
.visit_ty(ty
);
726 visitor
.visit_array_length(length
)
728 TyKind
::TraitObject(bounds
, ref lifetime
, _syntax
) => {
729 for bound
in bounds
{
730 visitor
.visit_poly_trait_ref(bound
, TraitBoundModifier
::None
);
732 visitor
.visit_lifetime(lifetime
);
734 TyKind
::Typeof(ref expression
) => visitor
.visit_anon_const(expression
),
735 TyKind
::Infer
| TyKind
::Err
=> {}
739 pub fn walk_inf
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, inf
: &'v InferArg
) {
740 visitor
.visit_id(inf
.hir_id
);
743 pub fn walk_qpath
<'v
, V
: Visitor
<'v
>>(
745 qpath
: &'v QPath
<'v
>,
750 QPath
::Resolved(ref maybe_qself
, ref path
) => {
751 walk_list
!(visitor
, visit_ty
, maybe_qself
);
752 visitor
.visit_path(path
, id
)
754 QPath
::TypeRelative(ref qself
, ref segment
) => {
755 visitor
.visit_ty(qself
);
756 visitor
.visit_path_segment(span
, segment
);
758 QPath
::LangItem(..) => {}
762 pub fn walk_path
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, path
: &'v Path
<'v
>) {
763 for segment
in path
.segments
{
764 visitor
.visit_path_segment(path
.span
, segment
);
768 pub fn walk_path_segment
<'v
, V
: Visitor
<'v
>>(
771 segment
: &'v PathSegment
<'v
>,
773 visitor
.visit_ident(segment
.ident
);
774 walk_list
!(visitor
, visit_id
, segment
.hir_id
);
775 if let Some(ref args
) = segment
.args
{
776 visitor
.visit_generic_args(path_span
, args
);
780 pub fn walk_generic_args
<'v
, V
: Visitor
<'v
>>(
783 generic_args
: &'v GenericArgs
<'v
>,
785 walk_list
!(visitor
, visit_generic_arg
, generic_args
.args
);
786 walk_list
!(visitor
, visit_assoc_type_binding
, generic_args
.bindings
);
789 pub fn walk_assoc_type_binding
<'v
, V
: Visitor
<'v
>>(
791 type_binding
: &'v TypeBinding
<'v
>,
793 visitor
.visit_id(type_binding
.hir_id
);
794 visitor
.visit_ident(type_binding
.ident
);
795 visitor
.visit_generic_args(type_binding
.span
, type_binding
.gen_args
);
796 match type_binding
.kind
{
797 TypeBindingKind
::Equality { ref term }
=> match term
{
798 Term
::Ty(ref ty
) => visitor
.visit_ty(ty
),
799 Term
::Const(ref c
) => visitor
.visit_anon_const(c
),
801 TypeBindingKind
::Constraint { bounds }
=> walk_list
!(visitor
, visit_param_bound
, bounds
),
805 pub fn walk_pat
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, pattern
: &'v Pat
<'v
>) {
806 visitor
.visit_id(pattern
.hir_id
);
808 PatKind
::TupleStruct(ref qpath
, children
, _
) => {
809 visitor
.visit_qpath(qpath
, pattern
.hir_id
, pattern
.span
);
810 walk_list
!(visitor
, visit_pat
, children
);
812 PatKind
::Path(ref qpath
) => {
813 visitor
.visit_qpath(qpath
, pattern
.hir_id
, pattern
.span
);
815 PatKind
::Struct(ref qpath
, fields
, _
) => {
816 visitor
.visit_qpath(qpath
, pattern
.hir_id
, pattern
.span
);
817 for field
in fields
{
818 visitor
.visit_id(field
.hir_id
);
819 visitor
.visit_ident(field
.ident
);
820 visitor
.visit_pat(&field
.pat
)
823 PatKind
::Or(pats
) => walk_list
!(visitor
, visit_pat
, pats
),
824 PatKind
::Tuple(tuple_elements
, _
) => {
825 walk_list
!(visitor
, visit_pat
, tuple_elements
);
827 PatKind
::Box(ref subpattern
) | PatKind
::Ref(ref subpattern
, _
) => {
828 visitor
.visit_pat(subpattern
)
830 PatKind
::Binding(_
, _hir_id
, ident
, ref optional_subpattern
) => {
831 visitor
.visit_ident(ident
);
832 walk_list
!(visitor
, visit_pat
, optional_subpattern
);
834 PatKind
::Lit(ref expression
) => visitor
.visit_expr(expression
),
835 PatKind
::Range(ref lower_bound
, ref upper_bound
, _
) => {
836 walk_list
!(visitor
, visit_expr
, lower_bound
);
837 walk_list
!(visitor
, visit_expr
, upper_bound
);
840 PatKind
::Slice(prepatterns
, ref slice_pattern
, postpatterns
) => {
841 walk_list
!(visitor
, visit_pat
, prepatterns
);
842 walk_list
!(visitor
, visit_pat
, slice_pattern
);
843 walk_list
!(visitor
, visit_pat
, postpatterns
);
848 pub fn walk_foreign_item
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, foreign_item
: &'v ForeignItem
<'v
>) {
849 visitor
.visit_id(foreign_item
.hir_id());
850 visitor
.visit_ident(foreign_item
.ident
);
852 match foreign_item
.kind
{
853 ForeignItemKind
::Fn(ref function_declaration
, param_names
, ref generics
) => {
854 visitor
.visit_generics(generics
);
855 visitor
.visit_fn_decl(function_declaration
);
856 for ¶m_name
in param_names
{
857 visitor
.visit_ident(param_name
);
860 ForeignItemKind
::Static(ref typ
, _
) => visitor
.visit_ty(typ
),
861 ForeignItemKind
::Type
=> (),
865 pub fn walk_param_bound
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, bound
: &'v GenericBound
<'v
>) {
867 GenericBound
::Trait(ref typ
, modifier
) => {
868 visitor
.visit_poly_trait_ref(typ
, modifier
);
870 GenericBound
::LangItemTrait(_
, span
, hir_id
, args
) => {
871 visitor
.visit_id(hir_id
);
872 visitor
.visit_generic_args(span
, args
);
874 GenericBound
::Outlives(ref lifetime
) => visitor
.visit_lifetime(lifetime
),
878 pub fn walk_generic_param
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, param
: &'v GenericParam
<'v
>) {
879 visitor
.visit_id(param
.hir_id
);
881 ParamName
::Plain(ident
) => visitor
.visit_ident(ident
),
882 ParamName
::Error
| ParamName
::Fresh
=> {}
885 GenericParamKind
::Lifetime { .. }
=> {}
886 GenericParamKind
::Type { ref default, .. }
=> walk_list
!(visitor
, visit_ty
, default),
887 GenericParamKind
::Const { ref ty, ref default }
=> {
888 visitor
.visit_ty(ty
);
889 if let Some(ref default) = default {
890 visitor
.visit_const_param_default(param
.hir_id
, default);
896 pub fn walk_const_param_default
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, ct
: &'v AnonConst
) {
897 visitor
.visit_anon_const(ct
)
900 pub fn walk_generics
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, generics
: &'v Generics
<'v
>) {
901 walk_list
!(visitor
, visit_generic_param
, generics
.params
);
902 walk_list
!(visitor
, visit_where_predicate
, generics
.predicates
);
905 pub fn walk_where_predicate
<'v
, V
: Visitor
<'v
>>(
907 predicate
: &'v WherePredicate
<'v
>,
910 WherePredicate
::BoundPredicate(WhereBoundPredicate
{
913 bound_generic_params
,
916 visitor
.visit_ty(bounded_ty
);
917 walk_list
!(visitor
, visit_param_bound
, bounds
);
918 walk_list
!(visitor
, visit_generic_param
, bound_generic_params
);
920 WherePredicate
::RegionPredicate(WhereRegionPredicate { ref lifetime, bounds, .. }
) => {
921 visitor
.visit_lifetime(lifetime
);
922 walk_list
!(visitor
, visit_param_bound
, bounds
);
924 WherePredicate
::EqPredicate(WhereEqPredicate
{
925 hir_id
, ref lhs_ty
, ref rhs_ty
, ..
927 visitor
.visit_id(hir_id
);
928 visitor
.visit_ty(lhs_ty
);
929 visitor
.visit_ty(rhs_ty
);
934 pub fn walk_fn_ret_ty
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, ret_ty
: &'v FnRetTy
<'v
>) {
935 if let FnRetTy
::Return(ref output_ty
) = *ret_ty
{
936 visitor
.visit_ty(output_ty
)
940 pub fn walk_fn_decl
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, function_declaration
: &'v FnDecl
<'v
>) {
941 for ty
in function_declaration
.inputs
{
944 walk_fn_ret_ty(visitor
, &function_declaration
.output
)
947 pub fn walk_fn_kind
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, function_kind
: FnKind
<'v
>) {
948 match function_kind
{
949 FnKind
::ItemFn(_
, generics
, ..) => {
950 visitor
.visit_generics(generics
);
952 FnKind
::Method(..) | FnKind
::Closure
=> {}
956 pub fn walk_fn
<'v
, V
: Visitor
<'v
>>(
958 function_kind
: FnKind
<'v
>,
959 function_declaration
: &'v FnDecl
<'v
>,
964 visitor
.visit_id(id
);
965 visitor
.visit_fn_decl(function_declaration
);
966 walk_fn_kind(visitor
, function_kind
);
967 visitor
.visit_nested_body(body_id
)
970 pub fn walk_trait_item
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, trait_item
: &'v TraitItem
<'v
>) {
971 visitor
.visit_ident(trait_item
.ident
);
972 visitor
.visit_generics(&trait_item
.generics
);
973 match trait_item
.kind
{
974 TraitItemKind
::Const(ref ty
, default) => {
975 visitor
.visit_id(trait_item
.hir_id());
976 visitor
.visit_ty(ty
);
977 walk_list
!(visitor
, visit_nested_body
, default);
979 TraitItemKind
::Fn(ref sig
, TraitFn
::Required(param_names
)) => {
980 visitor
.visit_id(trait_item
.hir_id());
981 visitor
.visit_fn_decl(&sig
.decl
);
982 for ¶m_name
in param_names
{
983 visitor
.visit_ident(param_name
);
986 TraitItemKind
::Fn(ref sig
, TraitFn
::Provided(body_id
)) => {
988 FnKind
::Method(trait_item
.ident
, sig
),
995 TraitItemKind
::Type(bounds
, ref default) => {
996 visitor
.visit_id(trait_item
.hir_id());
997 walk_list
!(visitor
, visit_param_bound
, bounds
);
998 walk_list
!(visitor
, visit_ty
, default);
1003 pub fn walk_trait_item_ref
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, trait_item_ref
: &'v TraitItemRef
) {
1004 // N.B., deliberately force a compilation error if/when new fields are added.
1005 let TraitItemRef { id, ident, ref kind, span: _, ref defaultness }
= *trait_item_ref
;
1006 visitor
.visit_nested_trait_item(id
);
1007 visitor
.visit_ident(ident
);
1008 visitor
.visit_associated_item_kind(kind
);
1009 visitor
.visit_defaultness(defaultness
);
1012 pub fn walk_impl_item
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, impl_item
: &'v ImplItem
<'v
>) {
1013 // N.B., deliberately force a compilation error if/when new fields are added.
1014 let ImplItem { def_id: _, ident, ref generics, ref kind, span: _, vis_span: _ }
= *impl_item
;
1016 visitor
.visit_ident(ident
);
1017 visitor
.visit_generics(generics
);
1019 ImplItemKind
::Const(ref ty
, body
) => {
1020 visitor
.visit_id(impl_item
.hir_id());
1021 visitor
.visit_ty(ty
);
1022 visitor
.visit_nested_body(body
);
1024 ImplItemKind
::Fn(ref sig
, body_id
) => {
1026 FnKind
::Method(impl_item
.ident
, sig
),
1033 ImplItemKind
::TyAlias(ref ty
) => {
1034 visitor
.visit_id(impl_item
.hir_id());
1035 visitor
.visit_ty(ty
);
1040 pub fn walk_foreign_item_ref
<'v
, V
: Visitor
<'v
>>(
1042 foreign_item_ref
: &'v ForeignItemRef
,
1044 // N.B., deliberately force a compilation error if/when new fields are added.
1045 let ForeignItemRef { id, ident, span: _ }
= *foreign_item_ref
;
1046 visitor
.visit_nested_foreign_item(id
);
1047 visitor
.visit_ident(ident
);
1050 pub fn walk_impl_item_ref
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, impl_item_ref
: &'v ImplItemRef
) {
1051 // N.B., deliberately force a compilation error if/when new fields are added.
1052 let ImplItemRef { id, ident, ref kind, span: _, ref defaultness, trait_item_def_id: _ }
=
1054 visitor
.visit_nested_impl_item(id
);
1055 visitor
.visit_ident(ident
);
1056 visitor
.visit_associated_item_kind(kind
);
1057 visitor
.visit_defaultness(defaultness
);
1060 pub fn walk_struct_def
<'v
, V
: Visitor
<'v
>>(
1062 struct_definition
: &'v VariantData
<'v
>,
1064 walk_list
!(visitor
, visit_id
, struct_definition
.ctor_hir_id());
1065 walk_list
!(visitor
, visit_field_def
, struct_definition
.fields());
1068 pub fn walk_field_def
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, field
: &'v FieldDef
<'v
>) {
1069 visitor
.visit_id(field
.hir_id
);
1070 visitor
.visit_ident(field
.ident
);
1071 visitor
.visit_ty(&field
.ty
);
1074 pub fn walk_block
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, block
: &'v Block
<'v
>) {
1075 visitor
.visit_id(block
.hir_id
);
1076 walk_list
!(visitor
, visit_stmt
, block
.stmts
);
1077 walk_list
!(visitor
, visit_expr
, &block
.expr
);
1080 pub fn walk_stmt
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, statement
: &'v Stmt
<'v
>) {
1081 visitor
.visit_id(statement
.hir_id
);
1082 match statement
.kind
{
1083 StmtKind
::Local(ref local
) => visitor
.visit_local(local
),
1084 StmtKind
::Item(item
) => visitor
.visit_nested_item(item
),
1085 StmtKind
::Expr(ref expression
) | StmtKind
::Semi(ref expression
) => {
1086 visitor
.visit_expr(expression
)
1091 pub fn walk_array_len
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, len
: &'v ArrayLen
) {
1093 &ArrayLen
::Infer(hir_id
, _span
) => visitor
.visit_id(hir_id
),
1094 ArrayLen
::Body(c
) => visitor
.visit_anon_const(c
),
1098 pub fn walk_anon_const
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, constant
: &'v AnonConst
) {
1099 visitor
.visit_id(constant
.hir_id
);
1100 visitor
.visit_nested_body(constant
.body
);
1103 pub fn walk_let_expr
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, let_expr
: &'v Let
<'v
>) {
1104 // match the visit order in walk_local
1105 visitor
.visit_expr(let_expr
.init
);
1106 visitor
.visit_id(let_expr
.hir_id
);
1107 visitor
.visit_pat(let_expr
.pat
);
1108 walk_list
!(visitor
, visit_ty
, let_expr
.ty
);
1111 pub fn walk_expr
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, expression
: &'v Expr
<'v
>) {
1112 visitor
.visit_id(expression
.hir_id
);
1113 match expression
.kind
{
1114 ExprKind
::Box(ref subexpression
) => visitor
.visit_expr(subexpression
),
1115 ExprKind
::Array(subexpressions
) => {
1116 walk_list
!(visitor
, visit_expr
, subexpressions
);
1118 ExprKind
::ConstBlock(ref anon_const
) => visitor
.visit_anon_const(anon_const
),
1119 ExprKind
::Repeat(ref element
, ref count
) => {
1120 visitor
.visit_expr(element
);
1121 visitor
.visit_array_length(count
)
1123 ExprKind
::Struct(ref qpath
, fields
, ref optional_base
) => {
1124 visitor
.visit_qpath(qpath
, expression
.hir_id
, expression
.span
);
1125 for field
in fields
{
1126 visitor
.visit_id(field
.hir_id
);
1127 visitor
.visit_ident(field
.ident
);
1128 visitor
.visit_expr(&field
.expr
)
1130 walk_list
!(visitor
, visit_expr
, optional_base
);
1132 ExprKind
::Tup(subexpressions
) => {
1133 walk_list
!(visitor
, visit_expr
, subexpressions
);
1135 ExprKind
::Call(ref callee_expression
, arguments
) => {
1136 visitor
.visit_expr(callee_expression
);
1137 walk_list
!(visitor
, visit_expr
, arguments
);
1139 ExprKind
::MethodCall(ref segment
, arguments
, _
) => {
1140 visitor
.visit_path_segment(expression
.span
, segment
);
1141 walk_list
!(visitor
, visit_expr
, arguments
);
1143 ExprKind
::Binary(_
, ref left_expression
, ref right_expression
) => {
1144 visitor
.visit_expr(left_expression
);
1145 visitor
.visit_expr(right_expression
)
1147 ExprKind
::AddrOf(_
, _
, ref subexpression
) | ExprKind
::Unary(_
, ref subexpression
) => {
1148 visitor
.visit_expr(subexpression
)
1150 ExprKind
::Cast(ref subexpression
, ref typ
) | ExprKind
::Type(ref subexpression
, ref typ
) => {
1151 visitor
.visit_expr(subexpression
);
1152 visitor
.visit_ty(typ
)
1154 ExprKind
::DropTemps(ref subexpression
) => {
1155 visitor
.visit_expr(subexpression
);
1157 ExprKind
::Let(ref let_expr
) => visitor
.visit_let_expr(let_expr
),
1158 ExprKind
::If(ref cond
, ref then
, ref else_opt
) => {
1159 visitor
.visit_expr(cond
);
1160 visitor
.visit_expr(then
);
1161 walk_list
!(visitor
, visit_expr
, else_opt
);
1163 ExprKind
::Loop(ref block
, ref opt_label
, _
, _
) => {
1164 walk_list
!(visitor
, visit_label
, opt_label
);
1165 visitor
.visit_block(block
);
1167 ExprKind
::Match(ref subexpression
, arms
, _
) => {
1168 visitor
.visit_expr(subexpression
);
1169 walk_list
!(visitor
, visit_arm
, arms
);
1172 bound_generic_params
,
1179 walk_list
!(visitor
, visit_generic_param
, bound_generic_params
);
1180 visitor
.visit_fn(FnKind
::Closure
, fn_decl
, body
, expression
.span
, expression
.hir_id
)
1182 ExprKind
::Block(ref block
, ref opt_label
) => {
1183 walk_list
!(visitor
, visit_label
, opt_label
);
1184 visitor
.visit_block(block
);
1186 ExprKind
::Assign(ref lhs
, ref rhs
, _
) => {
1187 visitor
.visit_expr(rhs
);
1188 visitor
.visit_expr(lhs
)
1190 ExprKind
::AssignOp(_
, ref left_expression
, ref right_expression
) => {
1191 visitor
.visit_expr(right_expression
);
1192 visitor
.visit_expr(left_expression
);
1194 ExprKind
::Field(ref subexpression
, ident
) => {
1195 visitor
.visit_expr(subexpression
);
1196 visitor
.visit_ident(ident
);
1198 ExprKind
::Index(ref main_expression
, ref index_expression
) => {
1199 visitor
.visit_expr(main_expression
);
1200 visitor
.visit_expr(index_expression
)
1202 ExprKind
::Path(ref qpath
) => {
1203 visitor
.visit_qpath(qpath
, expression
.hir_id
, expression
.span
);
1205 ExprKind
::Break(ref destination
, ref opt_expr
) => {
1206 walk_list
!(visitor
, visit_label
, &destination
.label
);
1207 walk_list
!(visitor
, visit_expr
, opt_expr
);
1209 ExprKind
::Continue(ref destination
) => {
1210 walk_list
!(visitor
, visit_label
, &destination
.label
);
1212 ExprKind
::Ret(ref optional_expression
) => {
1213 walk_list
!(visitor
, visit_expr
, optional_expression
);
1215 ExprKind
::InlineAsm(ref asm
) => {
1216 visitor
.visit_inline_asm(asm
, expression
.hir_id
);
1218 ExprKind
::Yield(ref subexpression
, _
) => {
1219 visitor
.visit_expr(subexpression
);
1221 ExprKind
::Lit(_
) | ExprKind
::Err
=> {}
1225 pub fn walk_arm
<'v
, V
: Visitor
<'v
>>(visitor
: &mut V
, arm
: &'v Arm
<'v
>) {
1226 visitor
.visit_id(arm
.hir_id
);
1227 visitor
.visit_pat(&arm
.pat
);
1228 if let Some(ref g
) = arm
.guard
{
1230 Guard
::If(ref e
) => visitor
.visit_expr(e
),
1231 Guard
::IfLet(ref l
) => {
1232 visitor
.visit_let_expr(l
);
1236 visitor
.visit_expr(&arm
.body
);
1239 pub fn walk_associated_item_kind
<'v
, V
: Visitor
<'v
>>(_
: &mut V
, _
: &'v AssocItemKind
) {
1240 // No visitable content here: this fn exists so you can call it if
1241 // the right thing to do, should content be added in the future,
1242 // would be to walk it.
1245 pub fn walk_defaultness
<'v
, V
: Visitor
<'v
>>(_
: &mut V
, _
: &'v Defaultness
) {
1246 // No visitable content here: this fn exists so you can call it if
1247 // the right thing to do, should content be added in the future,
1248 // would be to walk it.