1 use crate::def::{DefKind, Namespace, Res};
2 use crate::def_id::DefId;
3 crate use crate::hir_id::HirId;
4 use crate::{itemlikevisit, LangItem};
6 use rustc_ast::util::parser::ExprPrecedence;
7 use rustc_ast::{self as ast, CrateSugar, LlvmAsmDialect};
8 use rustc_ast::{AttrVec, Attribute, FloatTy, IntTy, Label, LitKind, StrStyle, UintTy};
9 pub use rustc_ast::{BorrowKind, ImplPolarity, IsAuto};
10 pub use rustc_ast::{CaptureBy, Movability, Mutability};
11 use rustc_ast::{InlineAsmOptions, InlineAsmTemplatePiece};
12 use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
13 use rustc_macros::HashStable_Generic;
14 use rustc_span::source_map::{SourceMap, Spanned};
15 use rustc_span::symbol::{kw, sym, Ident, Symbol};
16 use rustc_span::{def_id::LocalDefId, BytePos};
17 use rustc_span::{MultiSpan, Span, DUMMY_SP};
18 use rustc_target::asm::InlineAsmRegOrRegClass;
19 use rustc_target::spec::abi::Abi;
21 use smallvec::SmallVec;
22 use std::collections::{BTreeMap, BTreeSet};
25 #[derive(Copy, Clone, Encodable, HashStable_Generic)]
30 /// Either "`'a`", referring to a named lifetime definition,
31 /// or "``" (i.e., `kw::Empty`), for elision placeholders.
33 /// HIR lowering inserts these placeholders in type paths that
34 /// refer to type definitions needing lifetime parameters,
35 /// `&T` and `&mut T`, and trait objects without `... + 'a`.
36 pub name: LifetimeName,
39 #[derive(Debug, Clone, PartialEq, Eq, Encodable, Hash, Copy)]
40 #[derive(HashStable_Generic)]
42 /// Some user-given name like `T` or `'x`.
45 /// Synthetic name generated when user elided a lifetime in an impl header.
47 /// E.g., the lifetimes in cases like these:
50 /// impl Foo<'_> for u32
52 /// in that case, we rewrite to
54 /// impl<'f> Foo for &'f u32
55 /// impl<'f> Foo<'f> for u32
57 /// where `'f` is something like `Fresh(0)`. The indices are
58 /// unique per impl, but not necessarily continuous.
61 /// Indicates an illegal name was given and an error has been
62 /// reported (so we should squelch other derived errors). Occurs
63 /// when, e.g., `'_` is used in the wrong place.
68 pub fn ident(&self) -> Ident {
70 ParamName::Plain(ident) => ident,
71 ParamName::Fresh(_) | ParamName::Error => {
72 Ident::with_dummy_span(kw::UnderscoreLifetime)
77 pub fn normalize_to_macros_2_0(&self) -> ParamName {
79 ParamName::Plain(ident) => ParamName::Plain(ident.normalize_to_macros_2_0()),
80 param_name => param_name,
85 #[derive(Debug, Clone, PartialEq, Eq, Encodable, Hash, Copy)]
86 #[derive(HashStable_Generic)]
87 pub enum LifetimeName {
88 /// User-given names or fresh (synthetic) names.
91 /// User wrote nothing (e.g., the lifetime in `&u32`).
94 /// Implicit lifetime in a context like `dyn Foo`. This is
95 /// distinguished from implicit lifetimes elsewhere because the
96 /// lifetime that they default to must appear elsewhere within the
97 /// enclosing type. This means that, in an `impl Trait` context, we
98 /// don't have to create a parameter for them. That is, `impl
99 /// Trait<Item = &u32>` expands to an opaque type like `type
100 /// Foo<'a> = impl Trait<Item = &'a u32>`, but `impl Trait<item =
101 /// dyn Bar>` expands to `type Foo = impl Trait<Item = dyn Bar +
102 /// 'static>`. The latter uses `ImplicitObjectLifetimeDefault` so
103 /// that surrounding code knows not to create a lifetime
105 ImplicitObjectLifetimeDefault,
107 /// Indicates an error during lowering (usually `'_` in wrong place)
108 /// that was already reported.
111 /// User wrote specifies `'_`.
114 /// User wrote `'static`.
119 pub fn ident(&self) -> Ident {
121 LifetimeName::ImplicitObjectLifetimeDefault
122 | LifetimeName::Implicit
123 | LifetimeName::Error => Ident::invalid(),
124 LifetimeName::Underscore => Ident::with_dummy_span(kw::UnderscoreLifetime),
125 LifetimeName::Static => Ident::with_dummy_span(kw::StaticLifetime),
126 LifetimeName::Param(param_name) => param_name.ident(),
130 pub fn is_elided(&self) -> bool {
132 LifetimeName::ImplicitObjectLifetimeDefault
133 | LifetimeName::Implicit
134 | LifetimeName::Underscore => true,
136 // It might seem surprising that `Fresh(_)` counts as
137 // *not* elided -- but this is because, as far as the code
138 // in the compiler is concerned -- `Fresh(_)` variants act
139 // equivalently to "some fresh name". They correspond to
140 // early-bound regions on an impl, in other words.
141 LifetimeName::Error | LifetimeName::Param(_) | LifetimeName::Static => false,
145 fn is_static(&self) -> bool {
146 self == &LifetimeName::Static
149 pub fn normalize_to_macros_2_0(&self) -> LifetimeName {
151 LifetimeName::Param(param_name) => {
152 LifetimeName::Param(param_name.normalize_to_macros_2_0())
154 lifetime_name => lifetime_name,
159 impl fmt::Display for Lifetime {
160 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
161 self.name.ident().fmt(f)
165 impl fmt::Debug for Lifetime {
166 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
167 write!(f, "lifetime({}: {})", self.hir_id, self.name.ident())
172 pub fn is_elided(&self) -> bool {
173 self.name.is_elided()
176 pub fn is_static(&self) -> bool {
177 self.name.is_static()
181 /// A `Path` is essentially Rust's notion of a name; for instance,
182 /// `std::cmp::PartialEq`. It's represented as a sequence of identifiers,
183 /// along with a bunch of supporting information.
184 #[derive(Debug, HashStable_Generic)]
185 pub struct Path<'hir> {
187 /// The resolution for the path.
189 /// The segments in the path: the things separated by `::`.
190 pub segments: &'hir [PathSegment<'hir>],
194 pub fn is_global(&self) -> bool {
195 !self.segments.is_empty() && self.segments[0].ident.name == kw::PathRoot
199 /// A segment of a path: an identifier, an optional lifetime, and a set of
201 #[derive(Debug, HashStable_Generic)]
202 pub struct PathSegment<'hir> {
203 /// The identifier portion of this path segment.
204 #[stable_hasher(project(name))]
206 // `id` and `res` are optional. We currently only use these in save-analysis,
207 // any path segments without these will not have save-analysis info and
208 // therefore will not have 'jump to def' in IDEs, but otherwise will not be
209 // affected. (In general, we don't bother to get the defs for synthesized
210 // segments, only for segments which have come from the AST).
211 pub hir_id: Option<HirId>,
212 pub res: Option<Res>,
214 /// Type/lifetime parameters attached to this path. They come in
215 /// two flavors: `Path<A,B,C>` and `Path(A,B) -> C`. Note that
216 /// this is more than just simple syntactic sugar; the use of
217 /// parens affects the region binding rules, so we preserve the
219 pub args: Option<&'hir GenericArgs<'hir>>,
221 /// Whether to infer remaining type parameters, if any.
222 /// This only applies to expression and pattern paths, and
223 /// out of those only the segments with no type parameters
224 /// to begin with, e.g., `Vec::new` is `<Vec<..>>::new::<..>`.
225 pub infer_args: bool,
228 impl<'hir> PathSegment<'hir> {
229 /// Converts an identifier to the corresponding segment.
230 pub fn from_ident(ident: Ident) -> PathSegment<'hir> {
231 PathSegment { ident, hir_id: None, res: None, infer_args: true, args: None }
234 pub fn invalid() -> Self {
235 Self::from_ident(Ident::invalid())
238 pub fn args(&self) -> &GenericArgs<'hir> {
239 if let Some(ref args) = self.args {
242 const DUMMY: &GenericArgs<'_> = &GenericArgs::none();
248 #[derive(Encodable, Debug, HashStable_Generic)]
249 pub struct ConstArg {
250 pub value: AnonConst,
254 #[derive(Debug, HashStable_Generic)]
255 pub enum GenericArg<'hir> {
261 impl GenericArg<'_> {
262 pub fn span(&self) -> Span {
264 GenericArg::Lifetime(l) => l.span,
265 GenericArg::Type(t) => t.span,
266 GenericArg::Const(c) => c.span,
270 pub fn id(&self) -> HirId {
272 GenericArg::Lifetime(l) => l.hir_id,
273 GenericArg::Type(t) => t.hir_id,
274 GenericArg::Const(c) => c.value.hir_id,
278 pub fn is_const(&self) -> bool {
279 matches!(self, GenericArg::Const(_))
282 pub fn is_synthetic(&self) -> bool {
283 matches!(self, GenericArg::Lifetime(lifetime) if lifetime.name.ident() == Ident::invalid())
286 pub fn descr(&self) -> &'static str {
288 GenericArg::Lifetime(_) => "lifetime",
289 GenericArg::Type(_) => "type",
290 GenericArg::Const(_) => "constant",
294 pub fn to_ord(&self, feats: &rustc_feature::Features) -> ast::ParamKindOrd {
296 GenericArg::Lifetime(_) => ast::ParamKindOrd::Lifetime,
297 GenericArg::Type(_) => ast::ParamKindOrd::Type,
298 GenericArg::Const(_) => ast::ParamKindOrd::Const { unordered: feats.const_generics },
303 #[derive(Debug, HashStable_Generic)]
304 pub struct GenericArgs<'hir> {
305 /// The generic arguments for this path segment.
306 pub args: &'hir [GenericArg<'hir>],
307 /// Bindings (equality constraints) on associated types, if present.
308 /// E.g., `Foo<A = Bar>`.
309 pub bindings: &'hir [TypeBinding<'hir>],
310 /// Were arguments written in parenthesized form `Fn(T) -> U`?
311 /// This is required mostly for pretty-printing and diagnostics,
312 /// but also for changing lifetime elision rules to be "function-like".
313 pub parenthesized: bool,
316 impl GenericArgs<'_> {
317 pub const fn none() -> Self {
318 Self { args: &[], bindings: &[], parenthesized: false }
321 pub fn inputs(&self) -> &[Ty<'_>] {
322 if self.parenthesized {
323 for arg in self.args {
325 GenericArg::Lifetime(_) => {}
326 GenericArg::Type(ref ty) => {
327 if let TyKind::Tup(ref tys) = ty.kind {
332 GenericArg::Const(_) => {}
336 panic!("GenericArgs::inputs: not a `Fn(T) -> U`");
339 pub fn own_counts(&self) -> GenericParamCount {
340 // We could cache this as a property of `GenericParamCount`, but
341 // the aim is to refactor this away entirely eventually and the
342 // presence of this method will be a constant reminder.
343 let mut own_counts: GenericParamCount = Default::default();
345 for arg in self.args {
347 GenericArg::Lifetime(_) => own_counts.lifetimes += 1,
348 GenericArg::Type(_) => own_counts.types += 1,
349 GenericArg::Const(_) => own_counts.consts += 1,
356 pub fn span(&self) -> Option<Span> {
359 .filter(|arg| !arg.is_synthetic())
360 .map(|arg| arg.span())
361 .reduce(|span1, span2| span1.to(span2))
364 /// Returns span encompassing arguments and their surrounding `<>` or `()`
365 pub fn span_ext(&self, sm: &SourceMap) -> Option<Span> {
366 let mut span = self.span()?;
368 let (o, c) = if self.parenthesized { ('(', ')') } else { ('<', '>') };
370 if let Ok(snippet) = sm.span_to_snippet(span) {
371 let snippet = snippet.as_bytes();
373 if snippet[0] != (o as u8) || snippet[snippet.len() - 1] != (c as u8) {
374 span = sm.span_extend_to_prev_char(span, o, true);
375 span = span.with_lo(span.lo() - BytePos(1));
377 span = sm.span_extend_to_next_char(span, c, true);
378 span = span.with_hi(span.hi() + BytePos(1));
385 pub fn is_empty(&self) -> bool {
390 /// A modifier on a bound, currently this is only used for `?Sized`, where the
391 /// modifier is `Maybe`. Negative bounds should also be handled here.
392 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Hash, Debug)]
393 #[derive(HashStable_Generic)]
394 pub enum TraitBoundModifier {
400 /// The AST represents all type param bounds as types.
401 /// `typeck::collect::compute_bounds` matches these against
402 /// the "special" built-in traits (see `middle::lang_items`) and
403 /// detects `Copy`, `Send` and `Sync`.
404 #[derive(Debug, HashStable_Generic)]
405 pub enum GenericBound<'hir> {
406 Trait(PolyTraitRef<'hir>, TraitBoundModifier),
407 // FIXME(davidtwco): Introduce `PolyTraitRef::LangItem`
408 LangItemTrait(LangItem, Span, HirId, &'hir GenericArgs<'hir>),
412 impl GenericBound<'_> {
413 pub fn trait_ref(&self) -> Option<&TraitRef<'_>> {
415 GenericBound::Trait(data, _) => Some(&data.trait_ref),
420 pub fn span(&self) -> Span {
422 GenericBound::Trait(t, ..) => t.span,
423 GenericBound::LangItemTrait(_, span, ..) => *span,
424 GenericBound::Outlives(l) => l.span,
429 pub type GenericBounds<'hir> = &'hir [GenericBound<'hir>];
431 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Debug, HashStable_Generic)]
432 pub enum LifetimeParamKind {
433 // Indicates that the lifetime definition was explicitly declared (e.g., in
434 // `fn foo<'a>(x: &'a u8) -> &'a u8 { x }`).
437 // Indicates that the lifetime definition was synthetically added
438 // as a result of an in-band lifetime usage (e.g., in
439 // `fn foo(x: &'a u8) -> &'a u8 { x }`).
442 // Indication that the lifetime was elided (e.g., in both cases in
443 // `fn foo(x: &u8) -> &'_ u8 { x }`).
446 // Indication that the lifetime name was somehow in error.
450 #[derive(Debug, HashStable_Generic)]
451 pub enum GenericParamKind<'hir> {
452 /// A lifetime definition (e.g., `'a: 'b + 'c + 'd`).
454 kind: LifetimeParamKind,
457 default: Option<&'hir Ty<'hir>>,
458 synthetic: Option<SyntheticTyParamKind>,
462 /// Optional default value for the const generic param
463 default: Option<AnonConst>,
467 #[derive(Debug, HashStable_Generic)]
468 pub struct GenericParam<'hir> {
471 pub attrs: &'hir [Attribute],
472 pub bounds: GenericBounds<'hir>,
474 pub pure_wrt_drop: bool,
475 pub kind: GenericParamKind<'hir>,
478 impl GenericParam<'hir> {
479 pub fn bounds_span(&self) -> Option<Span> {
480 self.bounds.iter().fold(None, |span, bound| {
481 let span = span.map(|s| s.to(bound.span())).unwrap_or_else(|| bound.span());
489 pub struct GenericParamCount {
490 pub lifetimes: usize,
495 /// Represents lifetimes and type parameters attached to a declaration
496 /// of a function, enum, trait, etc.
497 #[derive(Debug, HashStable_Generic)]
498 pub struct Generics<'hir> {
499 pub params: &'hir [GenericParam<'hir>],
500 pub where_clause: WhereClause<'hir>,
504 impl Generics<'hir> {
505 pub const fn empty() -> Generics<'hir> {
508 where_clause: WhereClause { predicates: &[], span: DUMMY_SP },
513 pub fn get_named(&self, name: Symbol) -> Option<&GenericParam<'_>> {
514 for param in self.params {
515 if name == param.name.ident().name {
522 pub fn spans(&self) -> MultiSpan {
523 if self.params.is_empty() {
526 self.params.iter().map(|p| p.span).collect::<Vec<Span>>().into()
531 /// Synthetic type parameters are converted to another form during lowering; this allows
532 /// us to track the original form they had, and is useful for error messages.
533 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
534 #[derive(HashStable_Generic)]
535 pub enum SyntheticTyParamKind {
537 // Created by the `#[rustc_synthetic]` attribute.
541 /// A where-clause in a definition.
542 #[derive(Debug, HashStable_Generic)]
543 pub struct WhereClause<'hir> {
544 pub predicates: &'hir [WherePredicate<'hir>],
545 // Only valid if predicates aren't empty.
549 impl WhereClause<'_> {
550 pub fn span(&self) -> Option<Span> {
551 if self.predicates.is_empty() { None } else { Some(self.span) }
554 /// The `WhereClause` under normal circumstances points at either the predicates or the empty
555 /// space where the `where` clause should be. Only of use for diagnostic suggestions.
556 pub fn span_for_predicates_or_empty_place(&self) -> Span {
560 /// `Span` where further predicates would be suggested, accounting for trailing commas, like
561 /// in `fn foo<T>(t: T) where T: Foo,` so we don't suggest two trailing commas.
562 pub fn tail_span_for_suggestion(&self) -> Span {
563 let end = self.span_for_predicates_or_empty_place().shrink_to_hi();
564 self.predicates.last().map_or(end, |p| p.span()).shrink_to_hi().to(end)
568 /// A single predicate in a where-clause.
569 #[derive(Debug, HashStable_Generic)]
570 pub enum WherePredicate<'hir> {
571 /// A type binding (e.g., `for<'c> Foo: Send + Clone + 'c`).
572 BoundPredicate(WhereBoundPredicate<'hir>),
573 /// A lifetime predicate (e.g., `'a: 'b + 'c`).
574 RegionPredicate(WhereRegionPredicate<'hir>),
575 /// An equality predicate (unsupported).
576 EqPredicate(WhereEqPredicate<'hir>),
579 impl WherePredicate<'_> {
580 pub fn span(&self) -> Span {
582 WherePredicate::BoundPredicate(p) => p.span,
583 WherePredicate::RegionPredicate(p) => p.span,
584 WherePredicate::EqPredicate(p) => p.span,
589 /// A type bound (e.g., `for<'c> Foo: Send + Clone + 'c`).
590 #[derive(Debug, HashStable_Generic)]
591 pub struct WhereBoundPredicate<'hir> {
593 /// Any generics from a `for` binding.
594 pub bound_generic_params: &'hir [GenericParam<'hir>],
595 /// The type being bounded.
596 pub bounded_ty: &'hir Ty<'hir>,
597 /// Trait and lifetime bounds (e.g., `Clone + Send + 'static`).
598 pub bounds: GenericBounds<'hir>,
601 /// A lifetime predicate (e.g., `'a: 'b + 'c`).
602 #[derive(Debug, HashStable_Generic)]
603 pub struct WhereRegionPredicate<'hir> {
605 pub lifetime: Lifetime,
606 pub bounds: GenericBounds<'hir>,
609 /// An equality predicate (e.g., `T = int`); currently unsupported.
610 #[derive(Debug, HashStable_Generic)]
611 pub struct WhereEqPredicate<'hir> {
614 pub lhs_ty: &'hir Ty<'hir>,
615 pub rhs_ty: &'hir Ty<'hir>,
618 #[derive(Encodable, Debug, HashStable_Generic)]
619 pub struct ModuleItems {
620 // Use BTreeSets here so items are in the same order as in the
621 // list of all items in Crate
622 pub items: BTreeSet<ItemId>,
623 pub trait_items: BTreeSet<TraitItemId>,
624 pub impl_items: BTreeSet<ImplItemId>,
625 pub foreign_items: BTreeSet<ForeignItemId>,
628 /// A type representing only the top-level module.
629 #[derive(Encodable, Debug, HashStable_Generic)]
630 pub struct CrateItem<'hir> {
631 pub module: Mod<'hir>,
632 pub attrs: &'hir [Attribute],
636 /// The top-level data structure that stores the entire contents of
637 /// the crate currently being compiled.
639 /// For more details, see the [rustc dev guide].
641 /// [rustc dev guide]: https://rustc-dev-guide.rust-lang.org/hir.html
643 pub struct Crate<'hir> {
644 pub item: CrateItem<'hir>,
645 pub exported_macros: &'hir [MacroDef<'hir>],
646 // Attributes from non-exported macros, kept only for collecting the library feature list.
647 pub non_exported_macro_attrs: &'hir [Attribute],
649 // N.B., we use a `BTreeMap` here so that `visit_all_items` iterates
650 // over the ids in increasing order. In principle it should not
651 // matter what order we visit things in, but in *practice* it
652 // does, because it can affect the order in which errors are
653 // detected, which in turn can make UI tests yield
654 // slightly different results.
655 pub items: BTreeMap<ItemId, Item<'hir>>,
657 pub trait_items: BTreeMap<TraitItemId, TraitItem<'hir>>,
658 pub impl_items: BTreeMap<ImplItemId, ImplItem<'hir>>,
659 pub foreign_items: BTreeMap<ForeignItemId, ForeignItem<'hir>>,
660 pub bodies: BTreeMap<BodyId, Body<'hir>>,
661 pub trait_impls: BTreeMap<DefId, Vec<LocalDefId>>,
663 /// A list of the body ids written out in the order in which they
664 /// appear in the crate. If you're going to process all the bodies
665 /// in the crate, you should iterate over this list rather than the keys
667 pub body_ids: Vec<BodyId>,
669 /// A list of modules written out in the order in which they
670 /// appear in the crate. This includes the main crate module.
671 pub modules: BTreeMap<LocalDefId, ModuleItems>,
672 /// A list of proc macro HirIds, written out in the order in which
673 /// they are declared in the static array generated by proc_macro_harness.
674 pub proc_macros: Vec<HirId>,
676 pub trait_map: BTreeMap<HirId, Vec<TraitCandidate>>,
680 pub fn item(&self, id: ItemId) -> &Item<'hir> {
684 pub fn trait_item(&self, id: TraitItemId) -> &TraitItem<'hir> {
685 &self.trait_items[&id]
688 pub fn impl_item(&self, id: ImplItemId) -> &ImplItem<'hir> {
689 &self.impl_items[&id]
692 pub fn foreign_item(&self, id: ForeignItemId) -> &ForeignItem<'hir> {
693 &self.foreign_items[&id]
696 pub fn body(&self, id: BodyId) -> &Body<'hir> {
702 /// Visits all items in the crate in some deterministic (but
703 /// unspecified) order. If you just need to process every item,
704 /// but don't care about nesting, this method is the best choice.
706 /// If you do care about nesting -- usually because your algorithm
707 /// follows lexical scoping rules -- then you want a different
708 /// approach. You should override `visit_nested_item` in your
709 /// visitor and then call `intravisit::walk_crate` instead.
710 pub fn visit_all_item_likes<'hir, V>(&'hir self, visitor: &mut V)
712 V: itemlikevisit::ItemLikeVisitor<'hir>,
714 for item in self.items.values() {
715 visitor.visit_item(item);
718 for trait_item in self.trait_items.values() {
719 visitor.visit_trait_item(trait_item);
722 for impl_item in self.impl_items.values() {
723 visitor.visit_impl_item(impl_item);
726 for foreign_item in self.foreign_items.values() {
727 visitor.visit_foreign_item(foreign_item);
731 /// A parallel version of `visit_all_item_likes`.
732 pub fn par_visit_all_item_likes<'hir, V>(&'hir self, visitor: &V)
734 V: itemlikevisit::ParItemLikeVisitor<'hir> + Sync + Send,
738 par_for_each_in(&self.items, |(_, item)| {
739 visitor.visit_item(item);
743 par_for_each_in(&self.trait_items, |(_, trait_item)| {
744 visitor.visit_trait_item(trait_item);
748 par_for_each_in(&self.impl_items, |(_, impl_item)| {
749 visitor.visit_impl_item(impl_item);
753 par_for_each_in(&self.foreign_items, |(_, foreign_item)| {
754 visitor.visit_foreign_item(foreign_item);
761 /// A macro definition, in this crate or imported from another.
763 /// Not parsed directly, but created on macro import or `macro_rules!` expansion.
765 pub struct MacroDef<'hir> {
767 pub vis: Visibility<'hir>,
768 pub attrs: &'hir [Attribute],
769 pub def_id: LocalDefId,
771 pub ast: ast::MacroDef,
775 pub fn hir_id(&self) -> HirId {
776 HirId::make_owner(self.def_id)
780 /// A block of statements `{ .. }`, which may have a label (in this case the
781 /// `targeted_by_break` field will be `true`) and may be `unsafe` by means of
782 /// the `rules` being anything but `DefaultBlock`.
783 #[derive(Debug, HashStable_Generic)]
784 pub struct Block<'hir> {
785 /// Statements in a block.
786 pub stmts: &'hir [Stmt<'hir>],
787 /// An expression at the end of the block
788 /// without a semicolon, if any.
789 pub expr: Option<&'hir Expr<'hir>>,
790 #[stable_hasher(ignore)]
792 /// Distinguishes between `unsafe { ... }` and `{ ... }`.
793 pub rules: BlockCheckMode,
795 /// If true, then there may exist `break 'a` values that aim to
796 /// break out of this block early.
797 /// Used by `'label: {}` blocks and by `try {}` blocks.
798 pub targeted_by_break: bool,
801 #[derive(Debug, HashStable_Generic)]
802 pub struct Pat<'hir> {
803 #[stable_hasher(ignore)]
805 pub kind: PatKind<'hir>,
807 // Whether to use default binding modes.
808 // At present, this is false only for destructuring assignment.
809 pub default_binding_modes: bool,
812 impl<'hir> Pat<'hir> {
813 // FIXME(#19596) this is a workaround, but there should be a better way
814 fn walk_short_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) -> bool {
821 Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => true,
822 Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_short_(it),
823 Struct(_, fields, _) => fields.iter().all(|field| field.pat.walk_short_(it)),
824 TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().all(|p| p.walk_short_(it)),
825 Slice(before, slice, after) => {
826 before.iter().chain(slice.iter()).chain(after.iter()).all(|p| p.walk_short_(it))
831 /// Walk the pattern in left-to-right order,
832 /// short circuiting (with `.all(..)`) if `false` is returned.
834 /// Note that when visiting e.g. `Tuple(ps)`,
835 /// if visiting `ps[0]` returns `false`,
836 /// then `ps[1]` will not be visited.
837 pub fn walk_short(&self, mut it: impl FnMut(&Pat<'hir>) -> bool) -> bool {
838 self.walk_short_(&mut it)
841 // FIXME(#19596) this is a workaround, but there should be a better way
842 fn walk_(&self, it: &mut impl FnMut(&Pat<'hir>) -> bool) {
849 Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => {}
850 Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_(it),
851 Struct(_, fields, _) => fields.iter().for_each(|field| field.pat.walk_(it)),
852 TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().for_each(|p| p.walk_(it)),
853 Slice(before, slice, after) => {
854 before.iter().chain(slice.iter()).chain(after.iter()).for_each(|p| p.walk_(it))
859 /// Walk the pattern in left-to-right order.
861 /// If `it(pat)` returns `false`, the children are not visited.
862 pub fn walk(&self, mut it: impl FnMut(&Pat<'hir>) -> bool) {
866 /// Walk the pattern in left-to-right order.
868 /// If you always want to recurse, prefer this method over `walk`.
869 pub fn walk_always(&self, mut it: impl FnMut(&Pat<'_>)) {
877 /// A single field in a struct pattern.
879 /// Patterns like the fields of Foo `{ x, ref y, ref mut z }`
880 /// are treated the same as` x: x, y: ref y, z: ref mut z`,
881 /// except `is_shorthand` is true.
882 #[derive(Debug, HashStable_Generic)]
883 pub struct FieldPat<'hir> {
884 #[stable_hasher(ignore)]
886 /// The identifier for the field.
887 #[stable_hasher(project(name))]
889 /// The pattern the field is destructured to.
890 pub pat: &'hir Pat<'hir>,
891 pub is_shorthand: bool,
895 /// Explicit binding annotations given in the HIR for a binding. Note
896 /// that this is not the final binding *mode* that we infer after type
898 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
899 pub enum BindingAnnotation {
900 /// No binding annotation given: this means that the final binding mode
901 /// will depend on whether we have skipped through a `&` reference
902 /// when matching. For example, the `x` in `Some(x)` will have binding
903 /// mode `None`; if you do `let Some(x) = &Some(22)`, it will
904 /// ultimately be inferred to be by-reference.
906 /// Note that implicit reference skipping is not implemented yet (#42640).
909 /// Annotated with `mut x` -- could be either ref or not, similar to `None`.
912 /// Annotated as `ref`, like `ref x`
915 /// Annotated as `ref mut x`.
919 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
925 impl fmt::Display for RangeEnd {
926 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
927 f.write_str(match self {
928 RangeEnd::Included => "..=",
929 RangeEnd::Excluded => "..",
934 #[derive(Debug, HashStable_Generic)]
935 pub enum PatKind<'hir> {
936 /// Represents a wildcard pattern (i.e., `_`).
939 /// A fresh binding `ref mut binding @ OPT_SUBPATTERN`.
940 /// The `HirId` is the canonical ID for the variable being bound,
941 /// (e.g., in `Ok(x) | Err(x)`, both `x` use the same canonical ID),
942 /// which is the pattern ID of the first `x`.
943 Binding(BindingAnnotation, HirId, Ident, Option<&'hir Pat<'hir>>),
945 /// A struct or struct variant pattern (e.g., `Variant {x, y, ..}`).
946 /// The `bool` is `true` in the presence of a `..`.
947 Struct(QPath<'hir>, &'hir [FieldPat<'hir>], bool),
949 /// A tuple struct/variant pattern `Variant(x, y, .., z)`.
950 /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
951 /// `0 <= position <= subpats.len()`
952 TupleStruct(QPath<'hir>, &'hir [&'hir Pat<'hir>], Option<usize>),
954 /// An or-pattern `A | B | C`.
955 /// Invariant: `pats.len() >= 2`.
956 Or(&'hir [&'hir Pat<'hir>]),
958 /// A path pattern for an unit struct/variant or a (maybe-associated) constant.
961 /// A tuple pattern (e.g., `(a, b)`).
962 /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
963 /// `0 <= position <= subpats.len()`
964 Tuple(&'hir [&'hir Pat<'hir>], Option<usize>),
967 Box(&'hir Pat<'hir>),
969 /// A reference pattern (e.g., `&mut (a, b)`).
970 Ref(&'hir Pat<'hir>, Mutability),
973 Lit(&'hir Expr<'hir>),
975 /// A range pattern (e.g., `1..=2` or `1..2`).
976 Range(Option<&'hir Expr<'hir>>, Option<&'hir Expr<'hir>>, RangeEnd),
978 /// A slice pattern, `[before_0, ..., before_n, (slice, after_0, ..., after_n)?]`.
980 /// Here, `slice` is lowered from the syntax `($binding_mode $ident @)? ..`.
981 /// If `slice` exists, then `after` can be non-empty.
983 /// The representation for e.g., `[a, b, .., c, d]` is:
985 /// PatKind::Slice([Binding(a), Binding(b)], Some(Wild), [Binding(c), Binding(d)])
987 Slice(&'hir [&'hir Pat<'hir>], Option<&'hir Pat<'hir>>, &'hir [&'hir Pat<'hir>]),
990 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
992 /// The `+` operator (addition).
994 /// The `-` operator (subtraction).
996 /// The `*` operator (multiplication).
998 /// The `/` operator (division).
1000 /// The `%` operator (modulus).
1002 /// The `&&` operator (logical and).
1004 /// The `||` operator (logical or).
1006 /// The `^` operator (bitwise xor).
1008 /// The `&` operator (bitwise and).
1010 /// The `|` operator (bitwise or).
1012 /// The `<<` operator (shift left).
1014 /// The `>>` operator (shift right).
1016 /// The `==` operator (equality).
1018 /// The `<` operator (less than).
1020 /// The `<=` operator (less than or equal to).
1022 /// The `!=` operator (not equal to).
1024 /// The `>=` operator (greater than or equal to).
1026 /// The `>` operator (greater than).
1031 pub fn as_str(self) -> &'static str {
1033 BinOpKind::Add => "+",
1034 BinOpKind::Sub => "-",
1035 BinOpKind::Mul => "*",
1036 BinOpKind::Div => "/",
1037 BinOpKind::Rem => "%",
1038 BinOpKind::And => "&&",
1039 BinOpKind::Or => "||",
1040 BinOpKind::BitXor => "^",
1041 BinOpKind::BitAnd => "&",
1042 BinOpKind::BitOr => "|",
1043 BinOpKind::Shl => "<<",
1044 BinOpKind::Shr => ">>",
1045 BinOpKind::Eq => "==",
1046 BinOpKind::Lt => "<",
1047 BinOpKind::Le => "<=",
1048 BinOpKind::Ne => "!=",
1049 BinOpKind::Ge => ">=",
1050 BinOpKind::Gt => ">",
1054 pub fn is_lazy(self) -> bool {
1055 matches!(self, BinOpKind::And | BinOpKind::Or)
1058 pub fn is_shift(self) -> bool {
1059 matches!(self, BinOpKind::Shl | BinOpKind::Shr)
1062 pub fn is_comparison(self) -> bool {
1069 | BinOpKind::Ge => true,
1081 | BinOpKind::Shr => false,
1085 /// Returns `true` if the binary operator takes its arguments by value.
1086 pub fn is_by_value(self) -> bool {
1087 !self.is_comparison()
1091 impl Into<ast::BinOpKind> for BinOpKind {
1092 fn into(self) -> ast::BinOpKind {
1094 BinOpKind::Add => ast::BinOpKind::Add,
1095 BinOpKind::Sub => ast::BinOpKind::Sub,
1096 BinOpKind::Mul => ast::BinOpKind::Mul,
1097 BinOpKind::Div => ast::BinOpKind::Div,
1098 BinOpKind::Rem => ast::BinOpKind::Rem,
1099 BinOpKind::And => ast::BinOpKind::And,
1100 BinOpKind::Or => ast::BinOpKind::Or,
1101 BinOpKind::BitXor => ast::BinOpKind::BitXor,
1102 BinOpKind::BitAnd => ast::BinOpKind::BitAnd,
1103 BinOpKind::BitOr => ast::BinOpKind::BitOr,
1104 BinOpKind::Shl => ast::BinOpKind::Shl,
1105 BinOpKind::Shr => ast::BinOpKind::Shr,
1106 BinOpKind::Eq => ast::BinOpKind::Eq,
1107 BinOpKind::Lt => ast::BinOpKind::Lt,
1108 BinOpKind::Le => ast::BinOpKind::Le,
1109 BinOpKind::Ne => ast::BinOpKind::Ne,
1110 BinOpKind::Ge => ast::BinOpKind::Ge,
1111 BinOpKind::Gt => ast::BinOpKind::Gt,
1116 pub type BinOp = Spanned<BinOpKind>;
1118 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
1120 /// The `*` operator (deferencing).
1122 /// The `!` operator (logical negation).
1124 /// The `-` operator (negation).
1129 pub fn as_str(self) -> &'static str {
1137 /// Returns `true` if the unary operator takes its argument by value.
1138 pub fn is_by_value(self) -> bool {
1139 matches!(self, Self::Neg | Self::Not)
1144 #[derive(Debug, HashStable_Generic)]
1145 pub struct Stmt<'hir> {
1147 pub kind: StmtKind<'hir>,
1151 /// The contents of a statement.
1152 #[derive(Debug, HashStable_Generic)]
1153 pub enum StmtKind<'hir> {
1154 /// A local (`let`) binding.
1155 Local(&'hir Local<'hir>),
1157 /// An item binding.
1160 /// An expression without a trailing semi-colon (must have unit type).
1161 Expr(&'hir Expr<'hir>),
1163 /// An expression with a trailing semi-colon (may have any type).
1164 Semi(&'hir Expr<'hir>),
1167 impl<'hir> StmtKind<'hir> {
1168 pub fn attrs(&self, get_item: impl FnOnce(ItemId) -> &'hir Item<'hir>) -> &'hir [Attribute] {
1170 StmtKind::Local(ref l) => &l.attrs,
1171 StmtKind::Item(ref item_id) => &get_item(*item_id).attrs,
1172 StmtKind::Expr(ref e) | StmtKind::Semi(ref e) => &e.attrs,
1177 /// Represents a `let` statement (i.e., `let <pat>:<ty> = <expr>;`).
1178 #[derive(Debug, HashStable_Generic)]
1179 pub struct Local<'hir> {
1180 pub pat: &'hir Pat<'hir>,
1181 /// Type annotation, if any (otherwise the type will be inferred).
1182 pub ty: Option<&'hir Ty<'hir>>,
1183 /// Initializer expression to set the value, if any.
1184 pub init: Option<&'hir Expr<'hir>>,
1188 /// Can be `ForLoopDesugar` if the `let` statement is part of a `for` loop
1189 /// desugaring. Otherwise will be `Normal`.
1190 pub source: LocalSource,
1193 /// Represents a single arm of a `match` expression, e.g.
1194 /// `<pat> (if <guard>) => <body>`.
1195 #[derive(Debug, HashStable_Generic)]
1196 pub struct Arm<'hir> {
1197 #[stable_hasher(ignore)]
1200 pub attrs: &'hir [Attribute],
1201 /// If this pattern and the optional guard matches, then `body` is evaluated.
1202 pub pat: &'hir Pat<'hir>,
1203 /// Optional guard clause.
1204 pub guard: Option<Guard<'hir>>,
1205 /// The expression the arm evaluates to if this arm matches.
1206 pub body: &'hir Expr<'hir>,
1209 #[derive(Debug, HashStable_Generic)]
1210 pub enum Guard<'hir> {
1211 If(&'hir Expr<'hir>),
1212 IfLet(&'hir Pat<'hir>, &'hir Expr<'hir>),
1215 #[derive(Debug, HashStable_Generic)]
1216 pub struct Field<'hir> {
1217 #[stable_hasher(ignore)]
1220 pub expr: &'hir Expr<'hir>,
1222 pub is_shorthand: bool,
1225 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
1226 pub enum BlockCheckMode {
1228 UnsafeBlock(UnsafeSource),
1229 PushUnsafeBlock(UnsafeSource),
1230 PopUnsafeBlock(UnsafeSource),
1233 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
1234 pub enum UnsafeSource {
1239 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Hash, Debug)]
1244 /// The body of a function, closure, or constant value. In the case of
1245 /// a function, the body contains not only the function body itself
1246 /// (which is an expression), but also the argument patterns, since
1247 /// those are something that the caller doesn't really care about.
1252 /// fn foo((x, y): (u32, u32)) -> u32 {
1257 /// Here, the `Body` associated with `foo()` would contain:
1259 /// - an `params` array containing the `(x, y)` pattern
1260 /// - a `value` containing the `x + y` expression (maybe wrapped in a block)
1261 /// - `generator_kind` would be `None`
1263 /// All bodies have an **owner**, which can be accessed via the HIR
1264 /// map using `body_owner_def_id()`.
1266 pub struct Body<'hir> {
1267 pub params: &'hir [Param<'hir>],
1268 pub value: Expr<'hir>,
1269 pub generator_kind: Option<GeneratorKind>,
1273 pub fn id(&self) -> BodyId {
1274 BodyId { hir_id: self.value.hir_id }
1277 pub fn generator_kind(&self) -> Option<GeneratorKind> {
1282 /// The type of source expression that caused this generator to be created.
1283 #[derive(Clone, PartialEq, Eq, HashStable_Generic, Encodable, Decodable, Debug, Copy)]
1284 pub enum GeneratorKind {
1285 /// An explicit `async` block or the body of an async function.
1286 Async(AsyncGeneratorKind),
1288 /// A generator literal created via a `yield` inside a closure.
1292 impl fmt::Display for GeneratorKind {
1293 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1295 GeneratorKind::Async(k) => fmt::Display::fmt(k, f),
1296 GeneratorKind::Gen => f.write_str("generator"),
1301 /// In the case of a generator created as part of an async construct,
1302 /// which kind of async construct caused it to be created?
1304 /// This helps error messages but is also used to drive coercions in
1305 /// type-checking (see #60424).
1306 #[derive(Clone, PartialEq, Eq, HashStable_Generic, Encodable, Decodable, Debug, Copy)]
1307 pub enum AsyncGeneratorKind {
1308 /// An explicit `async` block written by the user.
1311 /// An explicit `async` block written by the user.
1314 /// The `async` block generated as the body of an async function.
1318 impl fmt::Display for AsyncGeneratorKind {
1319 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1320 f.write_str(match self {
1321 AsyncGeneratorKind::Block => "`async` block",
1322 AsyncGeneratorKind::Closure => "`async` closure body",
1323 AsyncGeneratorKind::Fn => "`async fn` body",
1328 #[derive(Copy, Clone, Debug)]
1329 pub enum BodyOwnerKind {
1330 /// Functions and methods.
1336 /// Constants and associated constants.
1339 /// Initializer of a `static` item.
1343 impl BodyOwnerKind {
1344 pub fn is_fn_or_closure(self) -> bool {
1346 BodyOwnerKind::Fn | BodyOwnerKind::Closure => true,
1347 BodyOwnerKind::Const | BodyOwnerKind::Static(_) => false,
1352 /// The kind of an item that requires const-checking.
1353 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
1354 pub enum ConstContext {
1358 /// A `static` or `static mut`.
1361 /// A `const`, associated `const`, or other const context.
1363 /// Other contexts include:
1364 /// - Array length expressions
1365 /// - Enum discriminants
1366 /// - Const generics
1368 /// For the most part, other contexts are treated just like a regular `const`, so they are
1369 /// lumped into the same category.
1374 /// A description of this const context that can appear between backticks in an error message.
1376 /// E.g. `const` or `static mut`.
1377 pub fn keyword_name(self) -> &'static str {
1379 Self::Const => "const",
1380 Self::Static(Mutability::Not) => "static",
1381 Self::Static(Mutability::Mut) => "static mut",
1382 Self::ConstFn => "const fn",
1387 /// A colloquial, trivially pluralizable description of this const context for use in error
1389 impl fmt::Display for ConstContext {
1390 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1392 Self::Const => write!(f, "constant"),
1393 Self::Static(_) => write!(f, "static"),
1394 Self::ConstFn => write!(f, "constant function"),
1400 pub type Lit = Spanned<LitKind>;
1402 /// A constant (expression) that's not an item or associated item,
1403 /// but needs its own `DefId` for type-checking, const-eval, etc.
1404 /// These are usually found nested inside types (e.g., array lengths)
1405 /// or expressions (e.g., repeat counts), and also used to define
1406 /// explicit discriminant values for enum variants.
1407 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Debug, HashStable_Generic)]
1408 pub struct AnonConst {
1415 pub struct Expr<'hir> {
1417 pub kind: ExprKind<'hir>,
1423 pub fn precedence(&self) -> ExprPrecedence {
1425 ExprKind::Box(_) => ExprPrecedence::Box,
1426 ExprKind::ConstBlock(_) => ExprPrecedence::ConstBlock,
1427 ExprKind::Array(_) => ExprPrecedence::Array,
1428 ExprKind::Call(..) => ExprPrecedence::Call,
1429 ExprKind::MethodCall(..) => ExprPrecedence::MethodCall,
1430 ExprKind::Tup(_) => ExprPrecedence::Tup,
1431 ExprKind::Binary(op, ..) => ExprPrecedence::Binary(op.node.into()),
1432 ExprKind::Unary(..) => ExprPrecedence::Unary,
1433 ExprKind::Lit(_) => ExprPrecedence::Lit,
1434 ExprKind::Type(..) | ExprKind::Cast(..) => ExprPrecedence::Cast,
1435 ExprKind::DropTemps(ref expr, ..) => expr.precedence(),
1436 ExprKind::If(..) => ExprPrecedence::If,
1437 ExprKind::Loop(..) => ExprPrecedence::Loop,
1438 ExprKind::Match(..) => ExprPrecedence::Match,
1439 ExprKind::Closure(..) => ExprPrecedence::Closure,
1440 ExprKind::Block(..) => ExprPrecedence::Block,
1441 ExprKind::Assign(..) => ExprPrecedence::Assign,
1442 ExprKind::AssignOp(..) => ExprPrecedence::AssignOp,
1443 ExprKind::Field(..) => ExprPrecedence::Field,
1444 ExprKind::Index(..) => ExprPrecedence::Index,
1445 ExprKind::Path(..) => ExprPrecedence::Path,
1446 ExprKind::AddrOf(..) => ExprPrecedence::AddrOf,
1447 ExprKind::Break(..) => ExprPrecedence::Break,
1448 ExprKind::Continue(..) => ExprPrecedence::Continue,
1449 ExprKind::Ret(..) => ExprPrecedence::Ret,
1450 ExprKind::InlineAsm(..) => ExprPrecedence::InlineAsm,
1451 ExprKind::LlvmInlineAsm(..) => ExprPrecedence::InlineAsm,
1452 ExprKind::Struct(..) => ExprPrecedence::Struct,
1453 ExprKind::Repeat(..) => ExprPrecedence::Repeat,
1454 ExprKind::Yield(..) => ExprPrecedence::Yield,
1455 ExprKind::Err => ExprPrecedence::Err,
1459 // Whether this looks like a place expr, without checking for deref
1461 // This will return `true` in some potentially surprising cases such as
1462 // `CONSTANT.field`.
1463 pub fn is_syntactic_place_expr(&self) -> bool {
1464 self.is_place_expr(|_| true)
1467 /// Whether this is a place expression.
1469 /// `allow_projections_from` should return `true` if indexing a field or index expression based
1470 /// on the given expression should be considered a place expression.
1471 pub fn is_place_expr(&self, mut allow_projections_from: impl FnMut(&Self) -> bool) -> bool {
1473 ExprKind::Path(QPath::Resolved(_, ref path)) => {
1474 matches!(path.res, Res::Local(..) | Res::Def(DefKind::Static, _) | Res::Err)
1477 // Type ascription inherits its place expression kind from its
1479 // https://github.com/rust-lang/rfcs/blob/master/text/0803-type-ascription.md#type-ascription-and-temporaries
1480 ExprKind::Type(ref e, _) => e.is_place_expr(allow_projections_from),
1482 ExprKind::Unary(UnOp::Deref, _) => true,
1484 ExprKind::Field(ref base, _) | ExprKind::Index(ref base, _) => {
1485 allow_projections_from(base) || base.is_place_expr(allow_projections_from)
1488 // Lang item paths cannot currently be local variables or statics.
1489 ExprKind::Path(QPath::LangItem(..)) => false,
1491 // Partially qualified paths in expressions can only legally
1492 // refer to associated items which are always rvalues.
1493 ExprKind::Path(QPath::TypeRelative(..))
1494 | ExprKind::Call(..)
1495 | ExprKind::MethodCall(..)
1496 | ExprKind::Struct(..)
1499 | ExprKind::Match(..)
1500 | ExprKind::Closure(..)
1501 | ExprKind::Block(..)
1502 | ExprKind::Repeat(..)
1503 | ExprKind::Array(..)
1504 | ExprKind::Break(..)
1505 | ExprKind::Continue(..)
1507 | ExprKind::Loop(..)
1508 | ExprKind::Assign(..)
1509 | ExprKind::InlineAsm(..)
1510 | ExprKind::LlvmInlineAsm(..)
1511 | ExprKind::AssignOp(..)
1513 | ExprKind::ConstBlock(..)
1514 | ExprKind::Unary(..)
1516 | ExprKind::AddrOf(..)
1517 | ExprKind::Binary(..)
1518 | ExprKind::Yield(..)
1519 | ExprKind::Cast(..)
1520 | ExprKind::DropTemps(..)
1521 | ExprKind::Err => false,
1525 /// If `Self.kind` is `ExprKind::DropTemps(expr)`, drill down until we get a non-`DropTemps`
1526 /// `Expr`. This is used in suggestions to ignore this `ExprKind` as it is semantically
1527 /// silent, only signaling the ownership system. By doing this, suggestions that check the
1528 /// `ExprKind` of any given `Expr` for presentation don't have to care about `DropTemps`
1529 /// beyond remembering to call this function before doing analysis on it.
1530 pub fn peel_drop_temps(&self) -> &Self {
1531 let mut expr = self;
1532 while let ExprKind::DropTemps(inner) = &expr.kind {
1539 /// Checks if the specified expression is a built-in range literal.
1540 /// (See: `LoweringContext::lower_expr()`).
1541 pub fn is_range_literal(expr: &Expr<'_>) -> bool {
1543 // All built-in range literals but `..=` and `..` desugar to `Struct`s.
1544 ExprKind::Struct(ref qpath, _, _) => matches!(
1549 | LangItem::RangeFrom
1550 | LangItem::RangeFull
1551 | LangItem::RangeToInclusive,
1556 // `..=` desugars into `::std::ops::RangeInclusive::new(...)`.
1557 ExprKind::Call(ref func, _) => {
1558 matches!(func.kind, ExprKind::Path(QPath::LangItem(LangItem::RangeInclusiveNew, _)))
1565 #[derive(Debug, HashStable_Generic)]
1566 pub enum ExprKind<'hir> {
1567 /// A `box x` expression.
1568 Box(&'hir Expr<'hir>),
1569 /// Allow anonymous constants from an inline `const` block
1570 ConstBlock(AnonConst),
1571 /// An array (e.g., `[a, b, c, d]`).
1572 Array(&'hir [Expr<'hir>]),
1573 /// A function call.
1575 /// The first field resolves to the function itself (usually an `ExprKind::Path`),
1576 /// and the second field is the list of arguments.
1577 /// This also represents calling the constructor of
1578 /// tuple-like ADTs such as tuple structs and enum variants.
1579 Call(&'hir Expr<'hir>, &'hir [Expr<'hir>]),
1580 /// A method call (e.g., `x.foo::<'static, Bar, Baz>(a, b, c, d)`).
1582 /// The `PathSegment`/`Span` represent the method name and its generic arguments
1583 /// (within the angle brackets).
1584 /// The first element of the vector of `Expr`s is the expression that evaluates
1585 /// to the object on which the method is being called on (the receiver),
1586 /// and the remaining elements are the rest of the arguments.
1587 /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as
1588 /// `ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d])`.
1589 /// The final `Span` represents the span of the function and arguments
1590 /// (e.g. `foo::<Bar, Baz>(a, b, c, d)` in `x.foo::<Bar, Baz>(a, b, c, d)`
1592 /// To resolve the called method to a `DefId`, call [`type_dependent_def_id`] with
1593 /// the `hir_id` of the `MethodCall` node itself.
1595 /// [`type_dependent_def_id`]: ../ty/struct.TypeckResults.html#method.type_dependent_def_id
1596 MethodCall(&'hir PathSegment<'hir>, Span, &'hir [Expr<'hir>], Span),
1597 /// A tuple (e.g., `(a, b, c, d)`).
1598 Tup(&'hir [Expr<'hir>]),
1599 /// A binary operation (e.g., `a + b`, `a * b`).
1600 Binary(BinOp, &'hir Expr<'hir>, &'hir Expr<'hir>),
1601 /// A unary operation (e.g., `!x`, `*x`).
1602 Unary(UnOp, &'hir Expr<'hir>),
1603 /// A literal (e.g., `1`, `"foo"`).
1605 /// A cast (e.g., `foo as f64`).
1606 Cast(&'hir Expr<'hir>, &'hir Ty<'hir>),
1607 /// A type reference (e.g., `Foo`).
1608 Type(&'hir Expr<'hir>, &'hir Ty<'hir>),
1609 /// Wraps the expression in a terminating scope.
1610 /// This makes it semantically equivalent to `{ let _t = expr; _t }`.
1612 /// This construct only exists to tweak the drop order in HIR lowering.
1613 /// An example of that is the desugaring of `for` loops.
1614 DropTemps(&'hir Expr<'hir>),
1615 /// An `if` block, with an optional else block.
1617 /// I.e., `if <expr> { <expr> } else { <expr> }`.
1618 If(&'hir Expr<'hir>, &'hir Expr<'hir>, Option<&'hir Expr<'hir>>),
1619 /// A conditionless loop (can be exited with `break`, `continue`, or `return`).
1621 /// I.e., `'label: loop { <block> }`.
1623 /// The `Span` is the loop header (`for x in y`/`while let pat = expr`).
1624 Loop(&'hir Block<'hir>, Option<Label>, LoopSource, Span),
1625 /// A `match` block, with a source that indicates whether or not it is
1626 /// the result of a desugaring, and if so, which kind.
1627 Match(&'hir Expr<'hir>, &'hir [Arm<'hir>], MatchSource),
1628 /// A closure (e.g., `move |a, b, c| {a + b + c}`).
1630 /// The `Span` is the argument block `|...|`.
1632 /// This may also be a generator literal or an `async block` as indicated by the
1633 /// `Option<Movability>`.
1634 Closure(CaptureBy, &'hir FnDecl<'hir>, BodyId, Span, Option<Movability>),
1635 /// A block (e.g., `'label: { ... }`).
1636 Block(&'hir Block<'hir>, Option<Label>),
1638 /// An assignment (e.g., `a = foo()`).
1639 Assign(&'hir Expr<'hir>, &'hir Expr<'hir>, Span),
1640 /// An assignment with an operator.
1643 AssignOp(BinOp, &'hir Expr<'hir>, &'hir Expr<'hir>),
1644 /// Access of a named (e.g., `obj.foo`) or unnamed (e.g., `obj.0`) struct or tuple field.
1645 Field(&'hir Expr<'hir>, Ident),
1646 /// An indexing operation (`foo[2]`).
1647 Index(&'hir Expr<'hir>, &'hir Expr<'hir>),
1649 /// Path to a definition, possibly containing lifetime or type parameters.
1652 /// A referencing operation (i.e., `&a` or `&mut a`).
1653 AddrOf(BorrowKind, Mutability, &'hir Expr<'hir>),
1654 /// A `break`, with an optional label to break.
1655 Break(Destination, Option<&'hir Expr<'hir>>),
1656 /// A `continue`, with an optional label.
1657 Continue(Destination),
1658 /// A `return`, with an optional value to be returned.
1659 Ret(Option<&'hir Expr<'hir>>),
1661 /// Inline assembly (from `asm!`), with its outputs and inputs.
1662 InlineAsm(&'hir InlineAsm<'hir>),
1663 /// Inline assembly (from `llvm_asm!`), with its outputs and inputs.
1664 LlvmInlineAsm(&'hir LlvmInlineAsm<'hir>),
1666 /// A struct or struct-like variant literal expression.
1668 /// E.g., `Foo {x: 1, y: 2}`, or `Foo {x: 1, .. base}`,
1669 /// where `base` is the `Option<Expr>`.
1670 Struct(&'hir QPath<'hir>, &'hir [Field<'hir>], Option<&'hir Expr<'hir>>),
1672 /// An array literal constructed from one repeated element.
1674 /// E.g., `[1; 5]`. The first expression is the element
1675 /// to be repeated; the second is the number of times to repeat it.
1676 Repeat(&'hir Expr<'hir>, AnonConst),
1678 /// A suspension point for generators (i.e., `yield <expr>`).
1679 Yield(&'hir Expr<'hir>, YieldSource),
1681 /// A placeholder for an expression that wasn't syntactically well formed in some way.
1685 /// Represents an optionally `Self`-qualified value/type path or associated extension.
1687 /// To resolve the path to a `DefId`, call [`qpath_res`].
1689 /// [`qpath_res`]: ../rustc_middle/ty/struct.TypeckResults.html#method.qpath_res
1690 #[derive(Debug, HashStable_Generic)]
1691 pub enum QPath<'hir> {
1692 /// Path to a definition, optionally "fully-qualified" with a `Self`
1693 /// type, if the path points to an associated item in a trait.
1695 /// E.g., an unqualified path like `Clone::clone` has `None` for `Self`,
1696 /// while `<Vec<T> as Clone>::clone` has `Some(Vec<T>)` for `Self`,
1697 /// even though they both have the same two-segment `Clone::clone` `Path`.
1698 Resolved(Option<&'hir Ty<'hir>>, &'hir Path<'hir>),
1700 /// Type-related paths (e.g., `<T>::default` or `<T>::Output`).
1701 /// Will be resolved by type-checking to an associated item.
1703 /// UFCS source paths can desugar into this, with `Vec::new` turning into
1704 /// `<Vec>::new`, and `T::X::Y::method` into `<<<T>::X>::Y>::method`,
1705 /// the `X` and `Y` nodes each being a `TyKind::Path(QPath::TypeRelative(..))`.
1706 TypeRelative(&'hir Ty<'hir>, &'hir PathSegment<'hir>),
1708 /// Reference to a `#[lang = "foo"]` item.
1709 LangItem(LangItem, Span),
1712 impl<'hir> QPath<'hir> {
1713 /// Returns the span of this `QPath`.
1714 pub fn span(&self) -> Span {
1716 QPath::Resolved(_, path) => path.span,
1717 QPath::TypeRelative(_, ps) => ps.ident.span,
1718 QPath::LangItem(_, span) => span,
1722 /// Returns the span of the qself of this `QPath`. For example, `()` in
1723 /// `<() as Trait>::method`.
1724 pub fn qself_span(&self) -> Span {
1726 QPath::Resolved(_, path) => path.span,
1727 QPath::TypeRelative(qself, _) => qself.span,
1728 QPath::LangItem(_, span) => span,
1732 /// Returns the span of the last segment of this `QPath`. For example, `method` in
1733 /// `<() as Trait>::method`.
1734 pub fn last_segment_span(&self) -> Span {
1736 QPath::Resolved(_, path) => path.segments.last().unwrap().ident.span,
1737 QPath::TypeRelative(_, segment) => segment.ident.span,
1738 QPath::LangItem(_, span) => span,
1743 /// Hints at the original code for a let statement.
1744 #[derive(Copy, Clone, Encodable, Debug, HashStable_Generic)]
1745 pub enum LocalSource {
1746 /// A `match _ { .. }`.
1748 /// A desugared `for _ in _ { .. }` loop.
1750 /// When lowering async functions, we create locals within the `async move` so that
1751 /// all parameters are dropped after the future is polled.
1753 /// ```ignore (pseudo-Rust)
1754 /// async fn foo(<pattern> @ x: Type) {
1756 /// let <pattern> = x;
1761 /// A desugared `<expr>.await`.
1763 /// A desugared `expr = expr`, where the LHS is a tuple, struct or array.
1764 /// The span is that of the `=` sign.
1765 AssignDesugar(Span),
1768 /// Hints at the original code for a `match _ { .. }`.
1769 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Hash, Debug)]
1770 #[derive(HashStable_Generic)]
1771 pub enum MatchSource {
1772 /// A `match _ { .. }`.
1774 /// An `if let _ = _ { .. }` (optionally with `else { .. }`).
1775 IfLetDesugar { contains_else_clause: bool },
1776 /// An `if let _ = _ => { .. }` match guard.
1778 /// A `while _ { .. }` (which was desugared to a `loop { match _ { .. } }`).
1780 /// A `while let _ = _ { .. }` (which was desugared to a
1781 /// `loop { match _ { .. } }`).
1783 /// A desugared `for _ in _ { .. }` loop.
1785 /// A desugared `?` operator.
1787 /// A desugared `<expr>.await`.
1792 pub fn name(self) -> &'static str {
1796 IfLetDesugar { .. } | IfLetGuardDesugar => "if",
1797 WhileDesugar | WhileLetDesugar => "while",
1798 ForLoopDesugar => "for",
1800 AwaitDesugar => ".await",
1805 /// The loop type that yielded an `ExprKind::Loop`.
1806 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
1807 pub enum LoopSource {
1808 /// A `loop { .. }` loop.
1810 /// A `while _ { .. }` loop.
1812 /// A `while let _ = _ { .. }` loop.
1814 /// A `for _ in _ { .. }` loop.
1819 pub fn name(self) -> &'static str {
1821 LoopSource::Loop => "loop",
1822 LoopSource::While | LoopSource::WhileLet => "while",
1823 LoopSource::ForLoop => "for",
1828 #[derive(Copy, Clone, Encodable, Debug, HashStable_Generic)]
1829 pub enum LoopIdError {
1831 UnlabeledCfInWhileCondition,
1835 impl fmt::Display for LoopIdError {
1836 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1837 f.write_str(match self {
1838 LoopIdError::OutsideLoopScope => "not inside loop scope",
1839 LoopIdError::UnlabeledCfInWhileCondition => {
1840 "unlabeled control flow (break or continue) in while condition"
1842 LoopIdError::UnresolvedLabel => "label not found",
1847 #[derive(Copy, Clone, Encodable, Debug, HashStable_Generic)]
1848 pub struct Destination {
1849 // This is `Some(_)` iff there is an explicit user-specified `label
1850 pub label: Option<Label>,
1852 // These errors are caught and then reported during the diagnostics pass in
1853 // librustc_passes/loops.rs
1854 pub target_id: Result<HirId, LoopIdError>,
1857 /// The yield kind that caused an `ExprKind::Yield`.
1858 #[derive(Copy, Clone, PartialEq, Eq, Debug, Encodable, Decodable, HashStable_Generic)]
1859 pub enum YieldSource {
1860 /// An `<expr>.await`.
1861 Await { expr: Option<HirId> },
1862 /// A plain `yield`.
1867 pub fn is_await(&self) -> bool {
1869 YieldSource::Await { .. } => true,
1870 YieldSource::Yield => false,
1875 impl fmt::Display for YieldSource {
1876 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1877 f.write_str(match self {
1878 YieldSource::Await { .. } => "`await`",
1879 YieldSource::Yield => "`yield`",
1884 impl From<GeneratorKind> for YieldSource {
1885 fn from(kind: GeneratorKind) -> Self {
1887 // Guess based on the kind of the current generator.
1888 GeneratorKind::Gen => Self::Yield,
1889 GeneratorKind::Async(_) => Self::Await { expr: None },
1894 // N.B., if you change this, you'll probably want to change the corresponding
1895 // type structure in middle/ty.rs as well.
1896 #[derive(Debug, HashStable_Generic)]
1897 pub struct MutTy<'hir> {
1898 pub ty: &'hir Ty<'hir>,
1899 pub mutbl: Mutability,
1902 /// Represents a function's signature in a trait declaration,
1903 /// trait implementation, or a free function.
1904 #[derive(Debug, HashStable_Generic)]
1905 pub struct FnSig<'hir> {
1906 pub header: FnHeader,
1907 pub decl: &'hir FnDecl<'hir>,
1911 // The bodies for items are stored "out of line", in a separate
1912 // hashmap in the `Crate`. Here we just record the hir-id of the item
1913 // so it can fetched later.
1914 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)]
1915 pub struct TraitItemId {
1916 pub def_id: LocalDefId,
1920 pub fn hir_id(&self) -> HirId {
1921 // Items are always HIR owners.
1922 HirId::make_owner(self.def_id)
1926 /// Represents an item declaration within a trait declaration,
1927 /// possibly including a default implementation. A trait item is
1928 /// either required (meaning it doesn't have an implementation, just a
1929 /// signature) or provided (meaning it has a default implementation).
1931 pub struct TraitItem<'hir> {
1933 pub def_id: LocalDefId,
1934 pub attrs: &'hir [Attribute],
1935 pub generics: Generics<'hir>,
1936 pub kind: TraitItemKind<'hir>,
1940 impl TraitItem<'_> {
1941 pub fn hir_id(&self) -> HirId {
1942 // Items are always HIR owners.
1943 HirId::make_owner(self.def_id)
1946 pub fn trait_item_id(&self) -> TraitItemId {
1947 TraitItemId { def_id: self.def_id }
1951 /// Represents a trait method's body (or just argument names).
1952 #[derive(Encodable, Debug, HashStable_Generic)]
1953 pub enum TraitFn<'hir> {
1954 /// No default body in the trait, just a signature.
1955 Required(&'hir [Ident]),
1957 /// Both signature and body are provided in the trait.
1961 /// Represents a trait method or associated constant or type
1962 #[derive(Debug, HashStable_Generic)]
1963 pub enum TraitItemKind<'hir> {
1964 /// An associated constant with an optional value (otherwise `impl`s must contain a value).
1965 Const(&'hir Ty<'hir>, Option<BodyId>),
1966 /// An associated function with an optional body.
1967 Fn(FnSig<'hir>, TraitFn<'hir>),
1968 /// An associated type with (possibly empty) bounds and optional concrete
1970 Type(GenericBounds<'hir>, Option<&'hir Ty<'hir>>),
1973 // The bodies for items are stored "out of line", in a separate
1974 // hashmap in the `Crate`. Here we just record the hir-id of the item
1975 // so it can fetched later.
1976 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)]
1977 pub struct ImplItemId {
1978 pub def_id: LocalDefId,
1982 pub fn hir_id(&self) -> HirId {
1983 // Items are always HIR owners.
1984 HirId::make_owner(self.def_id)
1988 /// Represents anything within an `impl` block.
1990 pub struct ImplItem<'hir> {
1992 pub def_id: LocalDefId,
1993 pub vis: Visibility<'hir>,
1994 pub defaultness: Defaultness,
1995 pub attrs: &'hir [Attribute],
1996 pub generics: Generics<'hir>,
1997 pub kind: ImplItemKind<'hir>,
2002 pub fn hir_id(&self) -> HirId {
2003 // Items are always HIR owners.
2004 HirId::make_owner(self.def_id)
2007 pub fn impl_item_id(&self) -> ImplItemId {
2008 ImplItemId { def_id: self.def_id }
2012 /// Represents various kinds of content within an `impl`.
2013 #[derive(Debug, HashStable_Generic)]
2014 pub enum ImplItemKind<'hir> {
2015 /// An associated constant of the given type, set to the constant result
2016 /// of the expression.
2017 Const(&'hir Ty<'hir>, BodyId),
2018 /// An associated function implementation with the given signature and body.
2019 Fn(FnSig<'hir>, BodyId),
2020 /// An associated type.
2021 TyAlias(&'hir Ty<'hir>),
2024 impl ImplItemKind<'_> {
2025 pub fn namespace(&self) -> Namespace {
2027 ImplItemKind::TyAlias(..) => Namespace::TypeNS,
2028 ImplItemKind::Const(..) | ImplItemKind::Fn(..) => Namespace::ValueNS,
2033 // The name of the associated type for `Fn` return types.
2034 pub const FN_OUTPUT_NAME: Symbol = sym::Output;
2036 /// Bind a type to an associated type (i.e., `A = Foo`).
2038 /// Bindings like `A: Debug` are represented as a special type `A =
2039 /// $::Debug` that is understood by the astconv code.
2041 /// FIXME(alexreg): why have a separate type for the binding case,
2042 /// wouldn't it be better to make the `ty` field an enum like the
2046 /// enum TypeBindingKind {
2051 #[derive(Debug, HashStable_Generic)]
2052 pub struct TypeBinding<'hir> {
2054 #[stable_hasher(project(name))]
2056 pub gen_args: &'hir GenericArgs<'hir>,
2057 pub kind: TypeBindingKind<'hir>,
2061 // Represents the two kinds of type bindings.
2062 #[derive(Debug, HashStable_Generic)]
2063 pub enum TypeBindingKind<'hir> {
2064 /// E.g., `Foo<Bar: Send>`.
2065 Constraint { bounds: &'hir [GenericBound<'hir>] },
2066 /// E.g., `Foo<Bar = ()>`.
2067 Equality { ty: &'hir Ty<'hir> },
2070 impl TypeBinding<'_> {
2071 pub fn ty(&self) -> &Ty<'_> {
2073 TypeBindingKind::Equality { ref ty } => ty,
2074 _ => panic!("expected equality type binding for parenthesized generic args"),
2080 pub struct Ty<'hir> {
2082 pub kind: TyKind<'hir>,
2086 /// Not represented directly in the AST; referred to by name through a `ty_path`.
2087 #[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
2088 #[derive(HashStable_Generic)]
2099 /// All of the primitive types
2100 pub const ALL: [Self; 17] = [
2101 // any changes here should also be reflected in `PrimTy::from_name`
2102 Self::Int(IntTy::I8),
2103 Self::Int(IntTy::I16),
2104 Self::Int(IntTy::I32),
2105 Self::Int(IntTy::I64),
2106 Self::Int(IntTy::I128),
2107 Self::Int(IntTy::Isize),
2108 Self::Uint(UintTy::U8),
2109 Self::Uint(UintTy::U16),
2110 Self::Uint(UintTy::U32),
2111 Self::Uint(UintTy::U64),
2112 Self::Uint(UintTy::U128),
2113 Self::Uint(UintTy::Usize),
2114 Self::Float(FloatTy::F32),
2115 Self::Float(FloatTy::F64),
2121 pub fn name_str(self) -> &'static str {
2123 PrimTy::Int(i) => i.name_str(),
2124 PrimTy::Uint(u) => u.name_str(),
2125 PrimTy::Float(f) => f.name_str(),
2126 PrimTy::Str => "str",
2127 PrimTy::Bool => "bool",
2128 PrimTy::Char => "char",
2132 pub fn name(self) -> Symbol {
2134 PrimTy::Int(i) => i.name(),
2135 PrimTy::Uint(u) => u.name(),
2136 PrimTy::Float(f) => f.name(),
2137 PrimTy::Str => sym::str,
2138 PrimTy::Bool => sym::bool,
2139 PrimTy::Char => sym::char,
2143 /// Returns the matching `PrimTy` for a `Symbol` such as "str" or "i32".
2144 /// Returns `None` if no matching type is found.
2145 pub fn from_name(name: Symbol) -> Option<Self> {
2146 let ty = match name {
2147 // any changes here should also be reflected in `PrimTy::ALL`
2148 sym::i8 => Self::Int(IntTy::I8),
2149 sym::i16 => Self::Int(IntTy::I16),
2150 sym::i32 => Self::Int(IntTy::I32),
2151 sym::i64 => Self::Int(IntTy::I64),
2152 sym::i128 => Self::Int(IntTy::I128),
2153 sym::isize => Self::Int(IntTy::Isize),
2154 sym::u8 => Self::Uint(UintTy::U8),
2155 sym::u16 => Self::Uint(UintTy::U16),
2156 sym::u32 => Self::Uint(UintTy::U32),
2157 sym::u64 => Self::Uint(UintTy::U64),
2158 sym::u128 => Self::Uint(UintTy::U128),
2159 sym::usize => Self::Uint(UintTy::Usize),
2160 sym::f32 => Self::Float(FloatTy::F32),
2161 sym::f64 => Self::Float(FloatTy::F64),
2162 sym::bool => Self::Bool,
2163 sym::char => Self::Char,
2164 sym::str => Self::Str,
2171 #[derive(Debug, HashStable_Generic)]
2172 pub struct BareFnTy<'hir> {
2173 pub unsafety: Unsafety,
2175 pub generic_params: &'hir [GenericParam<'hir>],
2176 pub decl: &'hir FnDecl<'hir>,
2177 pub param_names: &'hir [Ident],
2180 #[derive(Debug, HashStable_Generic)]
2181 pub struct OpaqueTy<'hir> {
2182 pub generics: Generics<'hir>,
2183 pub bounds: GenericBounds<'hir>,
2184 pub impl_trait_fn: Option<DefId>,
2185 pub origin: OpaqueTyOrigin,
2188 /// From whence the opaque type came.
2189 #[derive(Copy, Clone, Encodable, Decodable, Debug, HashStable_Generic)]
2190 pub enum OpaqueTyOrigin {
2195 /// `let _: impl Trait = ...`
2197 /// Impl trait in type aliases, consts, statics, bounds.
2201 /// The various kinds of types recognized by the compiler.
2202 #[derive(Debug, HashStable_Generic)]
2203 pub enum TyKind<'hir> {
2204 /// A variable length slice (i.e., `[T]`).
2205 Slice(&'hir Ty<'hir>),
2206 /// A fixed length array (i.e., `[T; n]`).
2207 Array(&'hir Ty<'hir>, AnonConst),
2208 /// A raw pointer (i.e., `*const T` or `*mut T`).
2210 /// A reference (i.e., `&'a T` or `&'a mut T`).
2211 Rptr(Lifetime, MutTy<'hir>),
2212 /// A bare function (e.g., `fn(usize) -> bool`).
2213 BareFn(&'hir BareFnTy<'hir>),
2214 /// The never type (`!`).
2216 /// A tuple (`(A, B, C, D, ...)`).
2217 Tup(&'hir [Ty<'hir>]),
2218 /// A path to a type definition (`module::module::...::Type`), or an
2219 /// associated type (e.g., `<Vec<T> as Trait>::Type` or `<T>::Target`).
2221 /// Type parameters may be stored in each `PathSegment`.
2223 /// A opaque type definition itself. This is currently only used for the
2224 /// `opaque type Foo: Trait` item that `impl Trait` in desugars to.
2226 /// The generic argument list contains the lifetimes (and in the future
2227 /// possibly parameters) that are actually bound on the `impl Trait`.
2228 OpaqueDef(ItemId, &'hir [GenericArg<'hir>]),
2229 /// A trait object type `Bound1 + Bound2 + Bound3`
2230 /// where `Bound` is a trait or a lifetime.
2231 TraitObject(&'hir [PolyTraitRef<'hir>], Lifetime),
2234 /// `TyKind::Infer` means the type should be inferred instead of it having been
2235 /// specified. This can appear anywhere in a type.
2237 /// Placeholder for a type that has failed to be defined.
2241 #[derive(Debug, HashStable_Generic)]
2242 pub enum InlineAsmOperand<'hir> {
2244 reg: InlineAsmRegOrRegClass,
2248 reg: InlineAsmRegOrRegClass,
2250 expr: Option<Expr<'hir>>,
2253 reg: InlineAsmRegOrRegClass,
2258 reg: InlineAsmRegOrRegClass,
2260 in_expr: Expr<'hir>,
2261 out_expr: Option<Expr<'hir>>,
2271 impl<'hir> InlineAsmOperand<'hir> {
2272 pub fn reg(&self) -> Option<InlineAsmRegOrRegClass> {
2274 Self::In { reg, .. }
2275 | Self::Out { reg, .. }
2276 | Self::InOut { reg, .. }
2277 | Self::SplitInOut { reg, .. } => Some(reg),
2278 Self::Const { .. } | Self::Sym { .. } => None,
2283 #[derive(Debug, HashStable_Generic)]
2284 pub struct InlineAsm<'hir> {
2285 pub template: &'hir [InlineAsmTemplatePiece],
2286 pub operands: &'hir [(InlineAsmOperand<'hir>, Span)],
2287 pub options: InlineAsmOptions,
2288 pub line_spans: &'hir [Span],
2291 #[derive(Copy, Clone, Encodable, Decodable, Debug, HashStable_Generic, PartialEq)]
2292 pub struct LlvmInlineAsmOutput {
2293 pub constraint: Symbol,
2295 pub is_indirect: bool,
2299 // NOTE(eddyb) This is used within MIR as well, so unlike the rest of the HIR,
2300 // it needs to be `Clone` and `Decodable` and use plain `Vec<T>` instead of
2301 // arena-allocated slice.
2302 #[derive(Clone, Encodable, Decodable, Debug, HashStable_Generic, PartialEq)]
2303 pub struct LlvmInlineAsmInner {
2305 pub asm_str_style: StrStyle,
2306 pub outputs: Vec<LlvmInlineAsmOutput>,
2307 pub inputs: Vec<Symbol>,
2308 pub clobbers: Vec<Symbol>,
2310 pub alignstack: bool,
2311 pub dialect: LlvmAsmDialect,
2314 #[derive(Debug, HashStable_Generic)]
2315 pub struct LlvmInlineAsm<'hir> {
2316 pub inner: LlvmInlineAsmInner,
2317 pub outputs_exprs: &'hir [Expr<'hir>],
2318 pub inputs_exprs: &'hir [Expr<'hir>],
2321 /// Represents a parameter in a function header.
2322 #[derive(Debug, HashStable_Generic)]
2323 pub struct Param<'hir> {
2324 pub attrs: &'hir [Attribute],
2326 pub pat: &'hir Pat<'hir>,
2331 /// Represents the header (not the body) of a function declaration.
2332 #[derive(Debug, HashStable_Generic)]
2333 pub struct FnDecl<'hir> {
2334 /// The types of the function's parameters.
2336 /// Additional argument data is stored in the function's [body](Body::params).
2337 pub inputs: &'hir [Ty<'hir>],
2338 pub output: FnRetTy<'hir>,
2339 pub c_variadic: bool,
2340 /// Does the function have an implicit self?
2341 pub implicit_self: ImplicitSelfKind,
2344 /// Represents what type of implicit self a function has, if any.
2345 #[derive(Copy, Clone, Encodable, Decodable, Debug, HashStable_Generic)]
2346 pub enum ImplicitSelfKind {
2347 /// Represents a `fn x(self);`.
2349 /// Represents a `fn x(mut self);`.
2351 /// Represents a `fn x(&self);`.
2353 /// Represents a `fn x(&mut self);`.
2355 /// Represents when a function does not have a self argument or
2356 /// when a function has a `self: X` argument.
2360 impl ImplicitSelfKind {
2361 /// Does this represent an implicit self?
2362 pub fn has_implicit_self(&self) -> bool {
2363 !matches!(*self, ImplicitSelfKind::None)
2367 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Debug)]
2368 #[derive(HashStable_Generic)]
2374 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, Encodable, Decodable, HashStable_Generic)]
2375 pub enum Defaultness {
2376 Default { has_value: bool },
2381 pub fn has_value(&self) -> bool {
2383 Defaultness::Default { has_value } => has_value,
2384 Defaultness::Final => true,
2388 pub fn is_final(&self) -> bool {
2389 *self == Defaultness::Final
2392 pub fn is_default(&self) -> bool {
2393 matches!(*self, Defaultness::Default { .. })
2397 #[derive(Debug, HashStable_Generic)]
2398 pub enum FnRetTy<'hir> {
2399 /// Return type is not specified.
2401 /// Functions default to `()` and
2402 /// closures default to inference. Span points to where return
2403 /// type would be inserted.
2404 DefaultReturn(Span),
2405 /// Everything else.
2406 Return(&'hir Ty<'hir>),
2410 pub fn span(&self) -> Span {
2412 Self::DefaultReturn(span) => span,
2413 Self::Return(ref ty) => ty.span,
2418 #[derive(Encodable, Debug)]
2419 pub struct Mod<'hir> {
2420 /// A span from the first token past `{` to the last token until `}`.
2421 /// For `mod foo;`, the inner span ranges from the first token
2422 /// to the last token in the external file.
2424 pub item_ids: &'hir [ItemId],
2427 #[derive(Encodable, Debug, HashStable_Generic)]
2428 pub struct GlobalAsm {
2432 #[derive(Debug, HashStable_Generic)]
2433 pub struct EnumDef<'hir> {
2434 pub variants: &'hir [Variant<'hir>],
2437 #[derive(Debug, HashStable_Generic)]
2438 pub struct Variant<'hir> {
2439 /// Name of the variant.
2440 #[stable_hasher(project(name))]
2442 /// Attributes of the variant.
2443 pub attrs: &'hir [Attribute],
2444 /// Id of the variant (not the constructor, see `VariantData::ctor_hir_id()`).
2446 /// Fields and constructor id of the variant.
2447 pub data: VariantData<'hir>,
2448 /// Explicit discriminant (e.g., `Foo = 1`).
2449 pub disr_expr: Option<AnonConst>,
2454 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
2456 /// One import, e.g., `use foo::bar` or `use foo::bar as baz`.
2457 /// Also produced for each element of a list `use`, e.g.
2458 /// `use foo::{a, b}` lowers to `use foo::a; use foo::b;`.
2461 /// Glob import, e.g., `use foo::*`.
2464 /// Degenerate list import, e.g., `use foo::{a, b}` produces
2465 /// an additional `use foo::{}` for performing checks such as
2466 /// unstable feature gating. May be removed in the future.
2470 /// References to traits in impls.
2472 /// `resolve` maps each `TraitRef`'s `ref_id` to its defining trait; that's all
2473 /// that the `ref_id` is for. Note that `ref_id`'s value is not the `HirId` of the
2474 /// trait being referred to but just a unique `HirId` that serves as a key
2475 /// within the resolution map.
2476 #[derive(Debug, HashStable_Generic)]
2477 pub struct TraitRef<'hir> {
2478 pub path: &'hir Path<'hir>,
2479 // Don't hash the `ref_id`. It is tracked via the thing it is used to access.
2480 #[stable_hasher(ignore)]
2481 pub hir_ref_id: HirId,
2485 /// Gets the `DefId` of the referenced trait. It _must_ actually be a trait or trait alias.
2486 pub fn trait_def_id(&self) -> Option<DefId> {
2487 match self.path.res {
2488 Res::Def(DefKind::Trait | DefKind::TraitAlias, did) => Some(did),
2490 _ => unreachable!(),
2495 #[derive(Debug, HashStable_Generic)]
2496 pub struct PolyTraitRef<'hir> {
2497 /// The `'a` in `for<'a> Foo<&'a T>`.
2498 pub bound_generic_params: &'hir [GenericParam<'hir>],
2500 /// The `Foo<&'a T>` in `for<'a> Foo<&'a T>`.
2501 pub trait_ref: TraitRef<'hir>,
2506 pub type Visibility<'hir> = Spanned<VisibilityKind<'hir>>;
2509 pub enum VisibilityKind<'hir> {
2512 Restricted { path: &'hir Path<'hir>, hir_id: HirId },
2516 impl VisibilityKind<'_> {
2517 pub fn is_pub(&self) -> bool {
2518 matches!(*self, VisibilityKind::Public)
2521 pub fn is_pub_restricted(&self) -> bool {
2523 VisibilityKind::Public | VisibilityKind::Inherited => false,
2524 VisibilityKind::Crate(..) | VisibilityKind::Restricted { .. } => true,
2529 #[derive(Debug, HashStable_Generic)]
2530 pub struct StructField<'hir> {
2532 #[stable_hasher(project(name))]
2534 pub vis: Visibility<'hir>,
2536 pub ty: &'hir Ty<'hir>,
2537 pub attrs: &'hir [Attribute],
2540 impl StructField<'_> {
2541 // Still necessary in couple of places
2542 pub fn is_positional(&self) -> bool {
2543 let first = self.ident.as_str().as_bytes()[0];
2544 (b'0'..=b'9').contains(&first)
2548 /// Fields and constructor IDs of enum variants and structs.
2549 #[derive(Debug, HashStable_Generic)]
2550 pub enum VariantData<'hir> {
2551 /// A struct variant.
2553 /// E.g., `Bar { .. }` as in `enum Foo { Bar { .. } }`.
2554 Struct(&'hir [StructField<'hir>], /* recovered */ bool),
2555 /// A tuple variant.
2557 /// E.g., `Bar(..)` as in `enum Foo { Bar(..) }`.
2558 Tuple(&'hir [StructField<'hir>], HirId),
2561 /// E.g., `Bar = ..` as in `enum Foo { Bar = .. }`.
2565 impl VariantData<'hir> {
2566 /// Return the fields of this variant.
2567 pub fn fields(&self) -> &'hir [StructField<'hir>] {
2569 VariantData::Struct(ref fields, ..) | VariantData::Tuple(ref fields, ..) => fields,
2574 /// Return the `HirId` of this variant's constructor, if it has one.
2575 pub fn ctor_hir_id(&self) -> Option<HirId> {
2577 VariantData::Struct(_, _) => None,
2578 VariantData::Tuple(_, hir_id) | VariantData::Unit(hir_id) => Some(hir_id),
2583 // The bodies for items are stored "out of line", in a separate
2584 // hashmap in the `Crate`. Here we just record the hir-id of the item
2585 // so it can fetched later.
2586 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug, Hash)]
2588 pub def_id: LocalDefId,
2592 pub fn hir_id(&self) -> HirId {
2593 // Items are always HIR owners.
2594 HirId::make_owner(self.def_id)
2600 /// The name might be a dummy name in case of anonymous items
2602 pub struct Item<'hir> {
2604 pub def_id: LocalDefId,
2605 pub attrs: &'hir [Attribute],
2606 pub kind: ItemKind<'hir>,
2607 pub vis: Visibility<'hir>,
2612 pub fn hir_id(&self) -> HirId {
2613 // Items are always HIR owners.
2614 HirId::make_owner(self.def_id)
2617 pub fn item_id(&self) -> ItemId {
2618 ItemId { def_id: self.def_id }
2622 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
2623 #[derive(Encodable, Decodable, HashStable_Generic)]
2630 pub fn prefix_str(&self) -> &'static str {
2632 Self::Unsafe => "unsafe ",
2638 impl fmt::Display for Unsafety {
2639 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2640 f.write_str(match *self {
2641 Self::Unsafe => "unsafe",
2642 Self::Normal => "normal",
2647 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
2648 #[derive(Encodable, Decodable, HashStable_Generic)]
2649 pub enum Constness {
2654 #[derive(Copy, Clone, Encodable, Debug, HashStable_Generic)]
2655 pub struct FnHeader {
2656 pub unsafety: Unsafety,
2657 pub constness: Constness,
2658 pub asyncness: IsAsync,
2663 pub fn is_const(&self) -> bool {
2664 matches!(&self.constness, Constness::Const)
2668 #[derive(Debug, HashStable_Generic)]
2669 pub enum ItemKind<'hir> {
2670 /// An `extern crate` item, with optional *original* crate name if the crate was renamed.
2672 /// E.g., `extern crate foo` or `extern crate foo_bar as foo`.
2673 ExternCrate(Option<Symbol>),
2675 /// `use foo::bar::*;` or `use foo::bar::baz as quux;`
2679 /// `use foo::bar::baz;` (with `as baz` implicitly on the right).
2680 Use(&'hir Path<'hir>, UseKind),
2682 /// A `static` item.
2683 Static(&'hir Ty<'hir>, Mutability, BodyId),
2685 Const(&'hir Ty<'hir>, BodyId),
2686 /// A function declaration.
2687 Fn(FnSig<'hir>, Generics<'hir>, BodyId),
2690 /// An external module, e.g. `extern { .. }`.
2691 ForeignMod { abi: Abi, items: &'hir [ForeignItemRef<'hir>] },
2692 /// Module-level inline assembly (from `global_asm!`).
2693 GlobalAsm(&'hir GlobalAsm),
2694 /// A type alias, e.g., `type Foo = Bar<u8>`.
2695 TyAlias(&'hir Ty<'hir>, Generics<'hir>),
2696 /// An opaque `impl Trait` type alias, e.g., `type Foo = impl Bar;`.
2697 OpaqueTy(OpaqueTy<'hir>),
2698 /// An enum definition, e.g., `enum Foo<A, B> {C<A>, D<B>}`.
2699 Enum(EnumDef<'hir>, Generics<'hir>),
2700 /// A struct definition, e.g., `struct Foo<A> {x: A}`.
2701 Struct(VariantData<'hir>, Generics<'hir>),
2702 /// A union definition, e.g., `union Foo<A, B> {x: A, y: B}`.
2703 Union(VariantData<'hir>, Generics<'hir>),
2704 /// A trait definition.
2705 Trait(IsAuto, Unsafety, Generics<'hir>, GenericBounds<'hir>, &'hir [TraitItemRef]),
2707 TraitAlias(Generics<'hir>, GenericBounds<'hir>),
2709 /// An implementation, e.g., `impl<A> Trait for Foo { .. }`.
2713 #[derive(Debug, HashStable_Generic)]
2714 pub struct Impl<'hir> {
2715 pub unsafety: Unsafety,
2716 pub polarity: ImplPolarity,
2717 pub defaultness: Defaultness,
2718 // We do not put a `Span` in `Defaultness` because it breaks foreign crate metadata
2719 // decoding as `Span`s cannot be decoded when a `Session` is not available.
2720 pub defaultness_span: Option<Span>,
2721 pub constness: Constness,
2722 pub generics: Generics<'hir>,
2724 /// The trait being implemented, if any.
2725 pub of_trait: Option<TraitRef<'hir>>,
2727 pub self_ty: &'hir Ty<'hir>,
2728 pub items: &'hir [ImplItemRef<'hir>],
2732 pub fn generics(&self) -> Option<&Generics<'_>> {
2734 ItemKind::Fn(_, ref generics, _)
2735 | ItemKind::TyAlias(_, ref generics)
2736 | ItemKind::OpaqueTy(OpaqueTy { ref generics, impl_trait_fn: None, .. })
2737 | ItemKind::Enum(_, ref generics)
2738 | ItemKind::Struct(_, ref generics)
2739 | ItemKind::Union(_, ref generics)
2740 | ItemKind::Trait(_, _, ref generics, _, _)
2741 | ItemKind::Impl(Impl { ref generics, .. }) => generics,
2747 /// A reference from an trait to one of its associated items. This
2748 /// contains the item's id, naturally, but also the item's name and
2749 /// some other high-level details (like whether it is an associated
2750 /// type or method, and whether it is public). This allows other
2751 /// passes to find the impl they want without loading the ID (which
2752 /// means fewer edges in the incremental compilation graph).
2753 #[derive(Encodable, Debug, HashStable_Generic)]
2754 pub struct TraitItemRef {
2755 pub id: TraitItemId,
2756 #[stable_hasher(project(name))]
2758 pub kind: AssocItemKind,
2760 pub defaultness: Defaultness,
2763 /// A reference from an impl to one of its associated items. This
2764 /// contains the item's ID, naturally, but also the item's name and
2765 /// some other high-level details (like whether it is an associated
2766 /// type or method, and whether it is public). This allows other
2767 /// passes to find the impl they want without loading the ID (which
2768 /// means fewer edges in the incremental compilation graph).
2769 #[derive(Debug, HashStable_Generic)]
2770 pub struct ImplItemRef<'hir> {
2772 #[stable_hasher(project(name))]
2774 pub kind: AssocItemKind,
2776 pub vis: Visibility<'hir>,
2777 pub defaultness: Defaultness,
2780 #[derive(Copy, Clone, PartialEq, Encodable, Debug, HashStable_Generic)]
2781 pub enum AssocItemKind {
2783 Fn { has_self: bool },
2787 // The bodies for items are stored "out of line", in a separate
2788 // hashmap in the `Crate`. Here we just record the hir-id of the item
2789 // so it can fetched later.
2790 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Debug)]
2791 pub struct ForeignItemId {
2792 pub def_id: LocalDefId,
2795 impl ForeignItemId {
2796 pub fn hir_id(&self) -> HirId {
2797 // Items are always HIR owners.
2798 HirId::make_owner(self.def_id)
2802 /// A reference from a foreign block to one of its items. This
2803 /// contains the item's ID, naturally, but also the item's name and
2804 /// some other high-level details (like whether it is an associated
2805 /// type or method, and whether it is public). This allows other
2806 /// passes to find the impl they want without loading the ID (which
2807 /// means fewer edges in the incremental compilation graph).
2808 #[derive(Debug, HashStable_Generic)]
2809 pub struct ForeignItemRef<'hir> {
2810 pub id: ForeignItemId,
2811 #[stable_hasher(project(name))]
2814 pub vis: Visibility<'hir>,
2818 pub struct ForeignItem<'hir> {
2820 pub attrs: &'hir [Attribute],
2821 pub kind: ForeignItemKind<'hir>,
2822 pub def_id: LocalDefId,
2824 pub vis: Visibility<'hir>,
2827 impl ForeignItem<'_> {
2828 pub fn hir_id(&self) -> HirId {
2829 // Items are always HIR owners.
2830 HirId::make_owner(self.def_id)
2833 pub fn foreign_item_id(&self) -> ForeignItemId {
2834 ForeignItemId { def_id: self.def_id }
2838 /// An item within an `extern` block.
2839 #[derive(Debug, HashStable_Generic)]
2840 pub enum ForeignItemKind<'hir> {
2841 /// A foreign function.
2842 Fn(&'hir FnDecl<'hir>, &'hir [Ident], Generics<'hir>),
2843 /// A foreign static item (`static ext: u8`).
2844 Static(&'hir Ty<'hir>, Mutability),
2849 /// A variable captured by a closure.
2850 #[derive(Debug, Copy, Clone, Encodable, HashStable_Generic)]
2852 // First span where it is accessed (there can be multiple).
2856 // The TraitCandidate's import_ids is empty if the trait is defined in the same module, and
2857 // has length > 0 if the trait is found through an chain of imports, starting with the
2858 // import/use statement in the scope where the trait is used.
2859 #[derive(Encodable, Decodable, Clone, Debug)]
2860 pub struct TraitCandidate {
2862 pub import_ids: SmallVec<[LocalDefId; 1]>,
2865 #[derive(Copy, Clone, Debug, HashStable_Generic)]
2866 pub enum Node<'hir> {
2867 Param(&'hir Param<'hir>),
2868 Item(&'hir Item<'hir>),
2869 ForeignItem(&'hir ForeignItem<'hir>),
2870 TraitItem(&'hir TraitItem<'hir>),
2871 ImplItem(&'hir ImplItem<'hir>),
2872 Variant(&'hir Variant<'hir>),
2873 Field(&'hir StructField<'hir>),
2874 AnonConst(&'hir AnonConst),
2875 Expr(&'hir Expr<'hir>),
2876 Stmt(&'hir Stmt<'hir>),
2877 PathSegment(&'hir PathSegment<'hir>),
2879 TraitRef(&'hir TraitRef<'hir>),
2880 Binding(&'hir Pat<'hir>),
2881 Pat(&'hir Pat<'hir>),
2882 Arm(&'hir Arm<'hir>),
2883 Block(&'hir Block<'hir>),
2884 Local(&'hir Local<'hir>),
2885 MacroDef(&'hir MacroDef<'hir>),
2887 /// `Ctor` refers to the constructor of an enum variant or struct. Only tuple or unit variants
2888 /// with synthesized constructors.
2889 Ctor(&'hir VariantData<'hir>),
2891 Lifetime(&'hir Lifetime),
2892 GenericParam(&'hir GenericParam<'hir>),
2893 Visibility(&'hir Visibility<'hir>),
2895 Crate(&'hir CrateItem<'hir>),
2898 impl<'hir> Node<'hir> {
2899 pub fn ident(&self) -> Option<Ident> {
2901 Node::TraitItem(TraitItem { ident, .. })
2902 | Node::ImplItem(ImplItem { ident, .. })
2903 | Node::ForeignItem(ForeignItem { ident, .. })
2904 | Node::Field(StructField { ident, .. })
2905 | Node::Variant(Variant { ident, .. })
2906 | Node::MacroDef(MacroDef { ident, .. })
2907 | Node::Item(Item { ident, .. }) => Some(*ident),
2912 pub fn fn_decl(&self) -> Option<&FnDecl<'hir>> {
2914 Node::TraitItem(TraitItem { kind: TraitItemKind::Fn(fn_sig, _), .. })
2915 | Node::ImplItem(ImplItem { kind: ImplItemKind::Fn(fn_sig, _), .. })
2916 | Node::Item(Item { kind: ItemKind::Fn(fn_sig, _, _), .. }) => Some(fn_sig.decl),
2917 Node::ForeignItem(ForeignItem { kind: ForeignItemKind::Fn(fn_decl, _, _), .. }) => {
2924 pub fn body_id(&self) -> Option<BodyId> {
2926 Node::TraitItem(TraitItem {
2927 kind: TraitItemKind::Fn(_, TraitFn::Provided(body_id)),
2930 | Node::ImplItem(ImplItem { kind: ImplItemKind::Fn(_, body_id), .. })
2931 | Node::Item(Item { kind: ItemKind::Fn(.., body_id), .. }) => Some(*body_id),
2936 pub fn generics(&self) -> Option<&'hir Generics<'hir>> {
2938 Node::TraitItem(TraitItem { generics, .. })
2939 | Node::ImplItem(ImplItem { generics, .. }) => Some(generics),
2940 Node::Item(item) => item.kind.generics(),
2945 pub fn hir_id(&self) -> Option<HirId> {
2947 Node::Item(Item { def_id, .. })
2948 | Node::TraitItem(TraitItem { def_id, .. })
2949 | Node::ImplItem(ImplItem { def_id, .. })
2950 | Node::ForeignItem(ForeignItem { def_id, .. })
2951 | Node::MacroDef(MacroDef { def_id, .. }) => Some(HirId::make_owner(*def_id)),
2952 Node::Field(StructField { hir_id, .. })
2953 | Node::AnonConst(AnonConst { hir_id, .. })
2954 | Node::Expr(Expr { hir_id, .. })
2955 | Node::Stmt(Stmt { hir_id, .. })
2956 | Node::Ty(Ty { hir_id, .. })
2957 | Node::Binding(Pat { hir_id, .. })
2958 | Node::Pat(Pat { hir_id, .. })
2959 | Node::Arm(Arm { hir_id, .. })
2960 | Node::Block(Block { hir_id, .. })
2961 | Node::Local(Local { hir_id, .. })
2962 | Node::Lifetime(Lifetime { hir_id, .. })
2963 | Node::Param(Param { hir_id, .. })
2964 | Node::GenericParam(GenericParam { hir_id, .. }) => Some(*hir_id),
2965 Node::TraitRef(TraitRef { hir_ref_id, .. }) => Some(*hir_ref_id),
2966 Node::PathSegment(PathSegment { hir_id, .. }) => *hir_id,
2967 Node::Variant(Variant { id, .. }) => Some(*id),
2968 Node::Ctor(variant) => variant.ctor_hir_id(),
2969 Node::Crate(_) | Node::Visibility(_) => None,
2974 // Some nodes are used a lot. Make sure they don't unintentionally get bigger.
2975 #[cfg(target_arch = "x86_64")]
2977 rustc_data_structures::static_assert_size!(super::Block<'static>, 48);
2978 rustc_data_structures::static_assert_size!(super::Expr<'static>, 72);
2979 rustc_data_structures::static_assert_size!(super::Pat<'static>, 88);
2980 rustc_data_structures::static_assert_size!(super::QPath<'static>, 24);
2981 rustc_data_structures::static_assert_size!(super::Ty<'static>, 72);
2983 rustc_data_structures::static_assert_size!(super::Item<'static>, 200);
2984 rustc_data_structures::static_assert_size!(super::TraitItem<'static>, 144);
2985 rustc_data_structures::static_assert_size!(super::ImplItem<'static>, 168);
2986 rustc_data_structures::static_assert_size!(super::ForeignItem<'static>, 152);