1 //! HIR datatypes. See the [rustc guide] for more info.
3 //! [rustc guide]: https://rust-lang.github.io/rustc-guide/hir.html
5 pub use self::BlockCheckMode::*;
6 pub use self::CaptureClause::*;
7 pub use self::FunctionRetTy::*;
8 pub use self::Mutability::*;
9 pub use self::PrimTy::*;
10 pub use self::UnOp::*;
11 pub use self::UnsafeSource::*;
13 use crate::hir::def::{Res, DefKind};
14 use crate::hir::def_id::{DefId, DefIndex, LocalDefId, CRATE_DEF_INDEX};
15 use crate::hir::ptr::P;
16 use crate::mir::mono::Linkage;
17 use crate::ty::AdtKind;
18 use crate::ty::query::Providers;
19 use crate::util::nodemap::{NodeMap, FxHashSet};
21 use errors::FatalError;
22 use syntax_pos::{Span, DUMMY_SP, MultiSpan};
23 use syntax::source_map::Spanned;
24 use syntax::ast::{self, CrateSugar, Ident, Name, NodeId, AsmDialect};
25 use syntax::ast::{Attribute, Label, LitKind, StrStyle, FloatTy, IntTy, UintTy};
26 use syntax::attr::{InlineAttr, OptimizeAttr};
27 use syntax::symbol::{Symbol, kw};
28 use syntax::tokenstream::TokenStream;
29 use syntax::util::parser::ExprPrecedence;
30 use rustc_target::spec::abi::Abi;
31 use rustc_data_structures::sync::{par_for_each_in, Send, Sync};
32 use rustc_data_structures::thin_vec::ThinVec;
33 use rustc_macros::HashStable;
34 use rustc_serialize::{self, Encoder, Encodable, Decoder, Decodable};
35 use std::collections::{BTreeSet, BTreeMap};
37 use smallvec::SmallVec;
39 /// HIR doesn't commit to a concrete storage type and has its own alias for a vector.
40 /// It can be `Vec`, `P<[T]>` or potentially `Box<[T]>`, or some other container with similar
41 /// behavior. Unlike AST, HIR is mostly a static structure, so we can use an owned slice instead
42 /// of `Vec` to avoid keeping extra capacity.
43 pub type HirVec<T> = P<[T]>;
45 macro_rules! hir_vec {
46 ($elem:expr; $n:expr) => (
47 $crate::hir::HirVec::from(vec![$elem; $n])
50 $crate::hir::HirVec::from(vec![$($x),*])
58 pub mod itemlikevisit;
66 /// Uniquely identifies a node in the HIR of the current crate. It is
67 /// composed of the `owner`, which is the `DefIndex` of the directly enclosing
68 /// `hir::Item`, `hir::TraitItem`, or `hir::ImplItem` (i.e., the closest "item-like"),
69 /// and the `local_id` which is unique within the given owner.
71 /// This two-level structure makes for more stable values: One can move an item
72 /// around within the source code, or add or remove stuff before it, without
73 /// the `local_id` part of the `HirId` changing, which is a very useful property in
74 /// incremental compilation where we have to persist things through changes to
76 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, PartialOrd, Ord)]
79 pub local_id: ItemLocalId,
83 pub fn owner_def_id(self) -> DefId {
84 DefId::local(self.owner)
87 pub fn owner_local_def_id(self) -> LocalDefId {
88 LocalDefId::from_def_id(DefId::local(self.owner))
92 impl rustc_serialize::UseSpecializedEncodable for HirId {
93 fn default_encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
105 impl rustc_serialize::UseSpecializedDecodable for HirId {
106 fn default_decode<D: Decoder>(d: &mut D) -> Result<HirId, D::Error> {
107 let owner = DefIndex::decode(d)?;
108 let local_id = ItemLocalId::decode(d)?;
117 impl fmt::Display for HirId {
118 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
119 write!(f, "{:?}", self)
123 // Hack to ensure that we don't try to access the private parts of `ItemLocalId` in this module.
124 mod item_local_id_inner {
125 use rustc_index::vec::Idx;
126 use rustc_macros::HashStable;
127 rustc_index::newtype_index! {
128 /// An `ItemLocalId` uniquely identifies something within a given "item-like";
129 /// that is, within a `hir::Item`, `hir::TraitItem`, or `hir::ImplItem`. There is no
130 /// guarantee that the numerical value of a given `ItemLocalId` corresponds to
131 /// the node's position within the owning item in any way, but there is a
132 /// guarantee that the `LocalItemId`s within an owner occupy a dense range of
133 /// integers starting at zero, so a mapping that maps all or most nodes within
134 /// an "item-like" to something else can be implemented by a `Vec` instead of a
135 /// tree or hash map.
136 pub struct ItemLocalId {
142 pub use self::item_local_id_inner::ItemLocalId;
144 /// The `HirId` corresponding to `CRATE_NODE_ID` and `CRATE_DEF_INDEX`.
145 pub const CRATE_HIR_ID: HirId = HirId {
146 owner: CRATE_DEF_INDEX,
147 local_id: ItemLocalId::from_u32_const(0)
150 pub const DUMMY_HIR_ID: HirId = HirId {
151 owner: CRATE_DEF_INDEX,
152 local_id: DUMMY_ITEM_LOCAL_ID,
155 pub const DUMMY_ITEM_LOCAL_ID: ItemLocalId = ItemLocalId::MAX;
157 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, HashStable)]
158 pub struct Lifetime {
162 /// Either "`'a`", referring to a named lifetime definition,
163 /// or "``" (i.e., `kw::Invalid`), for elision placeholders.
165 /// HIR lowering inserts these placeholders in type paths that
166 /// refer to type definitions needing lifetime parameters,
167 /// `&T` and `&mut T`, and trait objects without `... + 'a`.
168 pub name: LifetimeName,
171 #[derive(Debug, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Copy, HashStable)]
173 /// Some user-given name like `T` or `'x`.
176 /// Synthetic name generated when user elided a lifetime in an impl header.
178 /// E.g., the lifetimes in cases like these:
180 /// impl Foo for &u32
181 /// impl Foo<'_> for u32
183 /// in that case, we rewrite to
185 /// impl<'f> Foo for &'f u32
186 /// impl<'f> Foo<'f> for u32
188 /// where `'f` is something like `Fresh(0)`. The indices are
189 /// unique per impl, but not necessarily continuous.
192 /// Indicates an illegal name was given and an error has been
193 /// reported (so we should squelch other derived errors). Occurs
194 /// when, e.g., `'_` is used in the wrong place.
199 pub fn ident(&self) -> Ident {
201 ParamName::Plain(ident) => ident,
202 ParamName::Fresh(_) |
203 ParamName::Error => Ident::with_dummy_span(kw::UnderscoreLifetime),
207 pub fn modern(&self) -> ParamName {
209 ParamName::Plain(ident) => ParamName::Plain(ident.modern()),
210 param_name => param_name,
215 #[derive(Debug, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Copy, HashStable)]
216 pub enum LifetimeName {
217 /// User-given names or fresh (synthetic) names.
220 /// User wrote nothing (e.g., the lifetime in `&u32`).
223 /// Implicit lifetime in a context like `dyn Foo`. This is
224 /// distinguished from implicit lifetimes elsewhere because the
225 /// lifetime that they default to must appear elsewhere within the
226 /// enclosing type. This means that, in an `impl Trait` context, we
227 /// don't have to create a parameter for them. That is, `impl
228 /// Trait<Item = &u32>` expands to an opaque type like `type
229 /// Foo<'a> = impl Trait<Item = &'a u32>`, but `impl Trait<item =
230 /// dyn Bar>` expands to `type Foo = impl Trait<Item = dyn Bar +
231 /// 'static>`. The latter uses `ImplicitObjectLifetimeDefault` so
232 /// that surrounding code knows not to create a lifetime
234 ImplicitObjectLifetimeDefault,
236 /// Indicates an error during lowering (usually `'_` in wrong place)
237 /// that was already reported.
240 /// User wrote specifies `'_`.
243 /// User wrote `'static`.
248 pub fn ident(&self) -> Ident {
250 LifetimeName::ImplicitObjectLifetimeDefault
251 | LifetimeName::Implicit
252 | LifetimeName::Error => Ident::invalid(),
253 LifetimeName::Underscore => Ident::with_dummy_span(kw::UnderscoreLifetime),
254 LifetimeName::Static => Ident::with_dummy_span(kw::StaticLifetime),
255 LifetimeName::Param(param_name) => param_name.ident(),
259 pub fn is_elided(&self) -> bool {
261 LifetimeName::ImplicitObjectLifetimeDefault
262 | LifetimeName::Implicit
263 | LifetimeName::Underscore => true,
265 // It might seem surprising that `Fresh(_)` counts as
266 // *not* elided -- but this is because, as far as the code
267 // in the compiler is concerned -- `Fresh(_)` variants act
268 // equivalently to "some fresh name". They correspond to
269 // early-bound regions on an impl, in other words.
270 LifetimeName::Error | LifetimeName::Param(_) | LifetimeName::Static => false,
274 fn is_static(&self) -> bool {
275 self == &LifetimeName::Static
278 pub fn modern(&self) -> LifetimeName {
280 LifetimeName::Param(param_name) => LifetimeName::Param(param_name.modern()),
281 lifetime_name => lifetime_name,
286 impl fmt::Display for Lifetime {
287 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
288 self.name.ident().fmt(f)
292 impl fmt::Debug for Lifetime {
293 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
297 print::to_string(print::NO_ANN, |s| s.print_lifetime(self)))
302 pub fn is_elided(&self) -> bool {
303 self.name.is_elided()
306 pub fn is_static(&self) -> bool {
307 self.name.is_static()
311 /// A `Path` is essentially Rust's notion of a name; for instance,
312 /// `std::cmp::PartialEq`. It's represented as a sequence of identifiers,
313 /// along with a bunch of supporting information.
314 #[derive(RustcEncodable, RustcDecodable, HashStable)]
317 /// The resolution for the path.
319 /// The segments in the path: the things separated by `::`.
320 pub segments: HirVec<PathSegment>,
324 pub fn is_global(&self) -> bool {
325 !self.segments.is_empty() && self.segments[0].ident.name == kw::PathRoot
329 impl fmt::Debug for Path {
330 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
331 write!(f, "path({})", self)
335 impl fmt::Display for Path {
336 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
337 write!(f, "{}", print::to_string(print::NO_ANN, |s| s.print_path(self, false)))
341 /// A segment of a path: an identifier, an optional lifetime, and a set of
343 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
344 pub struct PathSegment {
345 /// The identifier portion of this path segment.
346 #[stable_hasher(project(name))]
348 // `id` and `res` are optional. We currently only use these in save-analysis,
349 // any path segments without these will not have save-analysis info and
350 // therefore will not have 'jump to def' in IDEs, but otherwise will not be
351 // affected. (In general, we don't bother to get the defs for synthesized
352 // segments, only for segments which have come from the AST).
353 pub hir_id: Option<HirId>,
354 pub res: Option<Res>,
356 /// Type/lifetime parameters attached to this path. They come in
357 /// two flavors: `Path<A,B,C>` and `Path(A,B) -> C`. Note that
358 /// this is more than just simple syntactic sugar; the use of
359 /// parens affects the region binding rules, so we preserve the
361 pub args: Option<P<GenericArgs>>,
363 /// Whether to infer remaining type parameters, if any.
364 /// This only applies to expression and pattern paths, and
365 /// out of those only the segments with no type parameters
366 /// to begin with, e.g., `Vec::new` is `<Vec<..>>::new::<..>`.
367 pub infer_args: bool,
371 /// Converts an identifier to the corresponding segment.
372 pub fn from_ident(ident: Ident) -> PathSegment {
384 hir_id: Option<HirId>,
394 args: if args.is_empty() {
402 pub fn generic_args(&self) -> &GenericArgs {
403 if let Some(ref args) = self.args {
406 const DUMMY: &GenericArgs = &GenericArgs::none();
412 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
413 pub struct ConstArg {
414 pub value: AnonConst,
418 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
419 pub enum GenericArg {
426 pub fn span(&self) -> Span {
428 GenericArg::Lifetime(l) => l.span,
429 GenericArg::Type(t) => t.span,
430 GenericArg::Const(c) => c.span,
434 pub fn id(&self) -> HirId {
436 GenericArg::Lifetime(l) => l.hir_id,
437 GenericArg::Type(t) => t.hir_id,
438 GenericArg::Const(c) => c.value.hir_id,
442 pub fn is_const(&self) -> bool {
444 GenericArg::Const(_) => true,
450 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
451 pub struct GenericArgs {
452 /// The generic arguments for this path segment.
453 pub args: HirVec<GenericArg>,
454 /// Bindings (equality constraints) on associated types, if present.
455 /// E.g., `Foo<A = Bar>`.
456 pub bindings: HirVec<TypeBinding>,
457 /// Were arguments written in parenthesized form `Fn(T) -> U`?
458 /// This is required mostly for pretty-printing and diagnostics,
459 /// but also for changing lifetime elision rules to be "function-like".
460 pub parenthesized: bool,
464 pub const fn none() -> Self {
467 bindings: HirVec::new(),
468 parenthesized: false,
472 pub fn is_empty(&self) -> bool {
473 self.args.is_empty() && self.bindings.is_empty() && !self.parenthesized
476 pub fn inputs(&self) -> &[Ty] {
477 if self.parenthesized {
478 for arg in &self.args {
480 GenericArg::Lifetime(_) => {}
481 GenericArg::Type(ref ty) => {
482 if let TyKind::Tup(ref tys) = ty.kind {
487 GenericArg::Const(_) => {}
491 bug!("GenericArgs::inputs: not a `Fn(T) -> U`");
494 pub fn own_counts(&self) -> GenericParamCount {
495 // We could cache this as a property of `GenericParamCount`, but
496 // the aim is to refactor this away entirely eventually and the
497 // presence of this method will be a constant reminder.
498 let mut own_counts: GenericParamCount = Default::default();
500 for arg in &self.args {
502 GenericArg::Lifetime(_) => own_counts.lifetimes += 1,
503 GenericArg::Type(_) => own_counts.types += 1,
504 GenericArg::Const(_) => own_counts.consts += 1,
512 /// A modifier on a bound, currently this is only used for `?Sized`, where the
513 /// modifier is `Maybe`. Negative bounds should also be handled here.
514 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, HashStable)]
515 pub enum TraitBoundModifier {
520 /// The AST represents all type param bounds as types.
521 /// `typeck::collect::compute_bounds` matches these against
522 /// the "special" built-in traits (see `middle::lang_items`) and
523 /// detects `Copy`, `Send` and `Sync`.
524 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
525 pub enum GenericBound {
526 Trait(PolyTraitRef, TraitBoundModifier),
531 pub fn span(&self) -> Span {
533 &GenericBound::Trait(ref t, ..) => t.span,
534 &GenericBound::Outlives(ref l) => l.span,
539 pub type GenericBounds = HirVec<GenericBound>;
541 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Debug, HashStable)]
542 pub enum LifetimeParamKind {
543 // Indicates that the lifetime definition was explicitly declared (e.g., in
544 // `fn foo<'a>(x: &'a u8) -> &'a u8 { x }`).
547 // Indicates that the lifetime definition was synthetically added
548 // as a result of an in-band lifetime usage (e.g., in
549 // `fn foo(x: &'a u8) -> &'a u8 { x }`).
552 // Indication that the lifetime was elided (e.g., in both cases in
553 // `fn foo(x: &u8) -> &'_ u8 { x }`).
556 // Indication that the lifetime name was somehow in error.
560 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
561 pub enum GenericParamKind {
562 /// A lifetime definition (e.g., `'a: 'b + 'c + 'd`).
564 kind: LifetimeParamKind,
567 default: Option<P<Ty>>,
568 synthetic: Option<SyntheticTyParamKind>,
575 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
576 pub struct GenericParam {
579 pub attrs: HirVec<Attribute>,
580 pub bounds: GenericBounds,
582 pub pure_wrt_drop: bool,
583 pub kind: GenericParamKind,
587 pub struct GenericParamCount {
588 pub lifetimes: usize,
593 /// Represents lifetimes and type parameters attached to a declaration
594 /// of a function, enum, trait, etc.
595 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
596 pub struct Generics {
597 pub params: HirVec<GenericParam>,
598 pub where_clause: WhereClause,
603 pub const fn empty() -> Generics {
605 params: HirVec::new(),
606 where_clause: WhereClause {
607 predicates: HirVec::new(),
614 pub fn own_counts(&self) -> GenericParamCount {
615 // We could cache this as a property of `GenericParamCount`, but
616 // the aim is to refactor this away entirely eventually and the
617 // presence of this method will be a constant reminder.
618 let mut own_counts: GenericParamCount = Default::default();
620 for param in &self.params {
622 GenericParamKind::Lifetime { .. } => own_counts.lifetimes += 1,
623 GenericParamKind::Type { .. } => own_counts.types += 1,
624 GenericParamKind::Const { .. } => own_counts.consts += 1,
631 pub fn get_named(&self, name: Symbol) -> Option<&GenericParam> {
632 for param in &self.params {
633 if name == param.name.ident().name {
640 pub fn spans(&self) -> MultiSpan {
641 if self.params.is_empty() {
644 self.params.iter().map(|p| p.span).collect::<Vec<Span>>().into()
649 /// Synthetic type parameters are converted to another form during lowering; this allows
650 /// us to track the original form they had, and is useful for error messages.
651 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, HashStable)]
652 pub enum SyntheticTyParamKind {
656 /// A where-clause in a definition.
657 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
658 pub struct WhereClause {
659 pub predicates: HirVec<WherePredicate>,
660 // Only valid if predicates isn't empty.
665 pub fn span(&self) -> Option<Span> {
666 if self.predicates.is_empty() {
673 /// The `WhereClause` under normal circumstances points at either the predicates or the empty
674 /// space where the `where` clause should be. Only of use for diagnostic suggestions.
675 pub fn span_for_predicates_or_empty_place(&self) -> Span {
680 /// A single predicate in a where-clause.
681 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
682 pub enum WherePredicate {
683 /// A type binding (e.g., `for<'c> Foo: Send + Clone + 'c`).
684 BoundPredicate(WhereBoundPredicate),
685 /// A lifetime predicate (e.g., `'a: 'b + 'c`).
686 RegionPredicate(WhereRegionPredicate),
687 /// An equality predicate (unsupported).
688 EqPredicate(WhereEqPredicate),
691 impl WherePredicate {
692 pub fn span(&self) -> Span {
694 &WherePredicate::BoundPredicate(ref p) => p.span,
695 &WherePredicate::RegionPredicate(ref p) => p.span,
696 &WherePredicate::EqPredicate(ref p) => p.span,
701 /// A type bound (e.g., `for<'c> Foo: Send + Clone + 'c`).
702 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
703 pub struct WhereBoundPredicate {
705 /// Any generics from a `for` binding.
706 pub bound_generic_params: HirVec<GenericParam>,
707 /// The type being bounded.
708 pub bounded_ty: P<Ty>,
709 /// Trait and lifetime bounds (e.g., `Clone + Send + 'static`).
710 pub bounds: GenericBounds,
713 /// A lifetime predicate (e.g., `'a: 'b + 'c`).
714 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
715 pub struct WhereRegionPredicate {
717 pub lifetime: Lifetime,
718 pub bounds: GenericBounds,
721 /// An equality predicate (e.g., `T = int`); currently unsupported.
722 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
723 pub struct WhereEqPredicate {
730 #[derive(RustcEncodable, RustcDecodable, Debug)]
731 pub struct ModuleItems {
732 // Use BTreeSets here so items are in the same order as in the
733 // list of all items in Crate
734 pub items: BTreeSet<HirId>,
735 pub trait_items: BTreeSet<TraitItemId>,
736 pub impl_items: BTreeSet<ImplItemId>,
739 /// The top-level data structure that stores the entire contents of
740 /// the crate currently being compiled.
742 /// For more details, see the [rustc guide].
744 /// [rustc guide]: https://rust-lang.github.io/rustc-guide/hir.html
745 #[derive(RustcEncodable, RustcDecodable, Debug)]
748 pub attrs: HirVec<Attribute>,
750 pub exported_macros: HirVec<MacroDef>,
751 // Attributes from non-exported macros, kept only for collecting the library feature list.
752 pub non_exported_macro_attrs: HirVec<Attribute>,
754 // N.B., we use a `BTreeMap` here so that `visit_all_items` iterates
755 // over the ids in increasing order. In principle it should not
756 // matter what order we visit things in, but in *practice* it
757 // does, because it can affect the order in which errors are
758 // detected, which in turn can make compile-fail tests yield
759 // slightly different results.
760 pub items: BTreeMap<HirId, Item>,
762 pub trait_items: BTreeMap<TraitItemId, TraitItem>,
763 pub impl_items: BTreeMap<ImplItemId, ImplItem>,
764 pub bodies: BTreeMap<BodyId, Body>,
765 pub trait_impls: BTreeMap<DefId, Vec<HirId>>,
767 /// A list of the body ids written out in the order in which they
768 /// appear in the crate. If you're going to process all the bodies
769 /// in the crate, you should iterate over this list rather than the keys
771 pub body_ids: Vec<BodyId>,
773 /// A list of modules written out in the order in which they
774 /// appear in the crate. This includes the main crate module.
775 pub modules: BTreeMap<HirId, ModuleItems>,
779 pub fn item(&self, id: HirId) -> &Item {
783 pub fn trait_item(&self, id: TraitItemId) -> &TraitItem {
784 &self.trait_items[&id]
787 pub fn impl_item(&self, id: ImplItemId) -> &ImplItem {
788 &self.impl_items[&id]
791 /// Visits all items in the crate in some deterministic (but
792 /// unspecified) order. If you just need to process every item,
793 /// but don't care about nesting, this method is the best choice.
795 /// If you do care about nesting -- usually because your algorithm
796 /// follows lexical scoping rules -- then you want a different
797 /// approach. You should override `visit_nested_item` in your
798 /// visitor and then call `intravisit::walk_crate` instead.
799 pub fn visit_all_item_likes<'hir, V>(&'hir self, visitor: &mut V)
800 where V: itemlikevisit::ItemLikeVisitor<'hir>
802 for (_, item) in &self.items {
803 visitor.visit_item(item);
806 for (_, trait_item) in &self.trait_items {
807 visitor.visit_trait_item(trait_item);
810 for (_, impl_item) in &self.impl_items {
811 visitor.visit_impl_item(impl_item);
815 /// A parallel version of `visit_all_item_likes`.
816 pub fn par_visit_all_item_likes<'hir, V>(&'hir self, visitor: &V)
817 where V: itemlikevisit::ParItemLikeVisitor<'hir> + Sync + Send
820 par_for_each_in(&self.items, |(_, item)| {
821 visitor.visit_item(item);
824 par_for_each_in(&self.trait_items, |(_, trait_item)| {
825 visitor.visit_trait_item(trait_item);
828 par_for_each_in(&self.impl_items, |(_, impl_item)| {
829 visitor.visit_impl_item(impl_item);
834 pub fn body(&self, id: BodyId) -> &Body {
839 /// A macro definition, in this crate or imported from another.
841 /// Not parsed directly, but created on macro import or `macro_rules!` expansion.
842 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
843 pub struct MacroDef {
846 pub attrs: HirVec<Attribute>,
849 pub body: TokenStream,
853 /// A block of statements `{ .. }`, which may have a label (in this case the
854 /// `targeted_by_break` field will be `true`) and may be `unsafe` by means of
855 /// the `rules` being anything but `DefaultBlock`.
856 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
858 /// Statements in a block.
859 pub stmts: HirVec<Stmt>,
860 /// An expression at the end of the block
861 /// without a semicolon, if any.
862 pub expr: Option<P<Expr>>,
863 #[stable_hasher(ignore)]
865 /// Distinguishes between `unsafe { ... }` and `{ ... }`.
866 pub rules: BlockCheckMode,
868 /// If true, then there may exist `break 'a` values that aim to
869 /// break out of this block early.
870 /// Used by `'label: {}` blocks and by `try {}` blocks.
871 pub targeted_by_break: bool,
874 #[derive(RustcEncodable, RustcDecodable, HashStable)]
876 #[stable_hasher(ignore)]
882 impl fmt::Debug for Pat {
883 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
884 write!(f, "pat({}: {})", self.hir_id,
885 print::to_string(print::NO_ANN, |s| s.print_pat(self)))
890 // FIXME(#19596) this is a workaround, but there should be a better way
891 fn walk_short_(&self, it: &mut impl FnMut(&Pat) -> bool) -> bool {
898 Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => true,
899 Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_short_(it),
900 Struct(_, fields, _) => fields.iter().all(|field| field.pat.walk_short_(it)),
901 TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().all(|p| p.walk_short_(it)),
902 Slice(before, slice, after) => {
906 .all(|p| p.walk_short_(it))
911 /// Walk the pattern in left-to-right order,
912 /// short circuiting (with `.all(..)`) if `false` is returned.
914 /// Note that when visiting e.g. `Tuple(ps)`,
915 /// if visiting `ps[0]` returns `false`,
916 /// then `ps[1]` will not be visited.
917 pub fn walk_short(&self, mut it: impl FnMut(&Pat) -> bool) -> bool {
918 self.walk_short_(&mut it)
921 // FIXME(#19596) this is a workaround, but there should be a better way
922 fn walk_(&self, it: &mut impl FnMut(&Pat) -> bool) {
929 Wild | Lit(_) | Range(..) | Binding(.., None) | Path(_) => {},
930 Box(s) | Ref(s, _) | Binding(.., Some(s)) => s.walk_(it),
931 Struct(_, fields, _) => fields.iter().for_each(|field| field.pat.walk_(it)),
932 TupleStruct(_, s, _) | Tuple(s, _) | Or(s) => s.iter().for_each(|p| p.walk_(it)),
933 Slice(before, slice, after) => {
937 .for_each(|p| p.walk_(it))
942 /// Walk the pattern in left-to-right order.
944 /// If `it(pat)` returns `false`, the children are not visited.
945 pub fn walk(&self, mut it: impl FnMut(&Pat) -> bool) {
950 /// A single field in a struct pattern.
952 /// Patterns like the fields of Foo `{ x, ref y, ref mut z }`
953 /// are treated the same as` x: x, y: ref y, z: ref mut z`,
954 /// except `is_shorthand` is true.
955 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
956 pub struct FieldPat {
957 #[stable_hasher(ignore)]
959 /// The identifier for the field.
960 #[stable_hasher(project(name))]
962 /// The pattern the field is destructured to.
964 pub is_shorthand: bool,
968 /// Explicit binding annotations given in the HIR for a binding. Note
969 /// that this is not the final binding *mode* that we infer after type
971 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
972 pub enum BindingAnnotation {
973 /// No binding annotation given: this means that the final binding mode
974 /// will depend on whether we have skipped through a `&` reference
975 /// when matching. For example, the `x` in `Some(x)` will have binding
976 /// mode `None`; if you do `let Some(x) = &Some(22)`, it will
977 /// ultimately be inferred to be by-reference.
979 /// Note that implicit reference skipping is not implemented yet (#42640).
982 /// Annotated with `mut x` -- could be either ref or not, similar to `None`.
985 /// Annotated as `ref`, like `ref x`
988 /// Annotated as `ref mut x`.
992 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
998 impl fmt::Display for RangeEnd {
999 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1000 f.write_str(match self {
1001 RangeEnd::Included => "..=",
1002 RangeEnd::Excluded => "..",
1007 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1009 /// Represents a wildcard pattern (i.e., `_`).
1012 /// A fresh binding `ref mut binding @ OPT_SUBPATTERN`.
1013 /// The `HirId` is the canonical ID for the variable being bound,
1014 /// (e.g., in `Ok(x) | Err(x)`, both `x` use the same canonical ID),
1015 /// which is the pattern ID of the first `x`.
1016 Binding(BindingAnnotation, HirId, Ident, Option<P<Pat>>),
1018 /// A struct or struct variant pattern (e.g., `Variant {x, y, ..}`).
1019 /// The `bool` is `true` in the presence of a `..`.
1020 Struct(QPath, HirVec<FieldPat>, bool),
1022 /// A tuple struct/variant pattern `Variant(x, y, .., z)`.
1023 /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
1024 /// `0 <= position <= subpats.len()`
1025 TupleStruct(QPath, HirVec<P<Pat>>, Option<usize>),
1027 /// An or-pattern `A | B | C`.
1028 /// Invariant: `pats.len() >= 2`.
1031 /// A path pattern for an unit struct/variant or a (maybe-associated) constant.
1034 /// A tuple pattern (e.g., `(a, b)`).
1035 /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position.
1036 /// `0 <= position <= subpats.len()`
1037 Tuple(HirVec<P<Pat>>, Option<usize>),
1039 /// A `box` pattern.
1042 /// A reference pattern (e.g., `&mut (a, b)`).
1043 Ref(P<Pat>, Mutability),
1048 /// A range pattern (e.g., `1..=2` or `1..2`).
1049 Range(P<Expr>, P<Expr>, RangeEnd),
1051 /// `[a, b, ..i, y, z]` is represented as:
1052 /// `PatKind::Slice(box [a, b], Some(i), box [y, z])`.
1053 Slice(HirVec<P<Pat>>, Option<P<Pat>>, HirVec<P<Pat>>),
1056 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, HashStable,
1057 RustcEncodable, RustcDecodable, Hash, Debug)]
1058 pub enum Mutability {
1064 /// Returns `MutMutable` only if both `self` and `other` are mutable.
1065 pub fn and(self, other: Self) -> Self {
1067 MutMutable => other,
1068 MutImmutable => MutImmutable,
1072 pub fn invert(self) -> Self {
1074 MutMutable => MutImmutable,
1075 MutImmutable => MutMutable,
1079 pub fn prefix_str(&self) -> &'static str {
1081 MutMutable => "mut ",
1087 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1088 pub enum BinOpKind {
1089 /// The `+` operator (addition).
1091 /// The `-` operator (subtraction).
1093 /// The `*` operator (multiplication).
1095 /// The `/` operator (division).
1097 /// The `%` operator (modulus).
1099 /// The `&&` operator (logical and).
1101 /// The `||` operator (logical or).
1103 /// The `^` operator (bitwise xor).
1105 /// The `&` operator (bitwise and).
1107 /// The `|` operator (bitwise or).
1109 /// The `<<` operator (shift left).
1111 /// The `>>` operator (shift right).
1113 /// The `==` operator (equality).
1115 /// The `<` operator (less than).
1117 /// The `<=` operator (less than or equal to).
1119 /// The `!=` operator (not equal to).
1121 /// The `>=` operator (greater than or equal to).
1123 /// The `>` operator (greater than).
1128 pub fn as_str(self) -> &'static str {
1130 BinOpKind::Add => "+",
1131 BinOpKind::Sub => "-",
1132 BinOpKind::Mul => "*",
1133 BinOpKind::Div => "/",
1134 BinOpKind::Rem => "%",
1135 BinOpKind::And => "&&",
1136 BinOpKind::Or => "||",
1137 BinOpKind::BitXor => "^",
1138 BinOpKind::BitAnd => "&",
1139 BinOpKind::BitOr => "|",
1140 BinOpKind::Shl => "<<",
1141 BinOpKind::Shr => ">>",
1142 BinOpKind::Eq => "==",
1143 BinOpKind::Lt => "<",
1144 BinOpKind::Le => "<=",
1145 BinOpKind::Ne => "!=",
1146 BinOpKind::Ge => ">=",
1147 BinOpKind::Gt => ">",
1151 pub fn is_lazy(self) -> bool {
1153 BinOpKind::And | BinOpKind::Or => true,
1158 pub fn is_shift(self) -> bool {
1160 BinOpKind::Shl | BinOpKind::Shr => true,
1165 pub fn is_comparison(self) -> bool {
1172 BinOpKind::Ge => true,
1184 BinOpKind::Shr => false,
1188 /// Returns `true` if the binary operator takes its arguments by value.
1189 pub fn is_by_value(self) -> bool {
1190 !self.is_comparison()
1194 impl Into<ast::BinOpKind> for BinOpKind {
1195 fn into(self) -> ast::BinOpKind {
1197 BinOpKind::Add => ast::BinOpKind::Add,
1198 BinOpKind::Sub => ast::BinOpKind::Sub,
1199 BinOpKind::Mul => ast::BinOpKind::Mul,
1200 BinOpKind::Div => ast::BinOpKind::Div,
1201 BinOpKind::Rem => ast::BinOpKind::Rem,
1202 BinOpKind::And => ast::BinOpKind::And,
1203 BinOpKind::Or => ast::BinOpKind::Or,
1204 BinOpKind::BitXor => ast::BinOpKind::BitXor,
1205 BinOpKind::BitAnd => ast::BinOpKind::BitAnd,
1206 BinOpKind::BitOr => ast::BinOpKind::BitOr,
1207 BinOpKind::Shl => ast::BinOpKind::Shl,
1208 BinOpKind::Shr => ast::BinOpKind::Shr,
1209 BinOpKind::Eq => ast::BinOpKind::Eq,
1210 BinOpKind::Lt => ast::BinOpKind::Lt,
1211 BinOpKind::Le => ast::BinOpKind::Le,
1212 BinOpKind::Ne => ast::BinOpKind::Ne,
1213 BinOpKind::Ge => ast::BinOpKind::Ge,
1214 BinOpKind::Gt => ast::BinOpKind::Gt,
1219 pub type BinOp = Spanned<BinOpKind>;
1221 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1223 /// The `*` operator (deferencing).
1225 /// The `!` operator (logical negation).
1227 /// The `-` operator (negation).
1232 pub fn as_str(self) -> &'static str {
1240 /// Returns `true` if the unary operator takes its argument by value.
1241 pub fn is_by_value(self) -> bool {
1243 UnNeg | UnNot => true,
1250 #[derive(RustcEncodable, RustcDecodable)]
1257 impl fmt::Debug for Stmt {
1258 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1259 write!(f, "stmt({}: {})", self.hir_id,
1260 print::to_string(print::NO_ANN, |s| s.print_stmt(self)))
1264 /// The contents of a statement.
1265 #[derive(RustcEncodable, RustcDecodable, HashStable)]
1267 /// A local (`let`) binding.
1270 /// An item binding.
1273 /// An expression without a trailing semi-colon (must have unit type).
1276 /// An expression with a trailing semi-colon (may have any type).
1281 pub fn attrs(&self) -> &[Attribute] {
1283 StmtKind::Local(ref l) => &l.attrs,
1284 StmtKind::Item(_) => &[],
1285 StmtKind::Expr(ref e) |
1286 StmtKind::Semi(ref e) => &e.attrs,
1291 /// Represents a `let` statement (i.e., `let <pat>:<ty> = <expr>;`).
1292 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1295 /// Type annotation, if any (otherwise the type will be inferred).
1296 pub ty: Option<P<Ty>>,
1297 /// Initializer expression to set the value, if any.
1298 pub init: Option<P<Expr>>,
1301 pub attrs: ThinVec<Attribute>,
1302 /// Can be `ForLoopDesugar` if the `let` statement is part of a `for` loop
1303 /// desugaring. Otherwise will be `Normal`.
1304 pub source: LocalSource,
1307 /// Represents a single arm of a `match` expression, e.g.
1308 /// `<pat> (if <guard>) => <body>`.
1309 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1311 #[stable_hasher(ignore)]
1314 pub attrs: HirVec<Attribute>,
1315 /// If this pattern and the optional guard matches, then `body` is evaluated.
1317 /// Optional guard clause.
1318 pub guard: Option<Guard>,
1319 /// The expression the arm evaluates to if this arm matches.
1323 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1328 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1330 #[stable_hasher(ignore)]
1335 pub is_shorthand: bool,
1338 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1339 pub enum BlockCheckMode {
1341 UnsafeBlock(UnsafeSource),
1342 PushUnsafeBlock(UnsafeSource),
1343 PopUnsafeBlock(UnsafeSource),
1346 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1347 pub enum UnsafeSource {
1352 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Hash, Debug)]
1357 /// The body of a function, closure, or constant value. In the case of
1358 /// a function, the body contains not only the function body itself
1359 /// (which is an expression), but also the argument patterns, since
1360 /// those are something that the caller doesn't really care about.
1365 /// fn foo((x, y): (u32, u32)) -> u32 {
1370 /// Here, the `Body` associated with `foo()` would contain:
1372 /// - an `params` array containing the `(x, y)` pattern
1373 /// - a `value` containing the `x + y` expression (maybe wrapped in a block)
1374 /// - `generator_kind` would be `None`
1376 /// All bodies have an **owner**, which can be accessed via the HIR
1377 /// map using `body_owner_def_id()`.
1378 #[derive(RustcEncodable, RustcDecodable, Debug)]
1380 pub params: HirVec<Param>,
1382 pub generator_kind: Option<GeneratorKind>,
1386 pub fn id(&self) -> BodyId {
1388 hir_id: self.value.hir_id,
1392 pub fn generator_kind(&self) -> Option<GeneratorKind> {
1397 /// The type of source expression that caused this generator to be created.
1398 #[derive(Clone, PartialEq, Eq, HashStable, RustcEncodable, RustcDecodable, Debug, Copy)]
1399 pub enum GeneratorKind {
1400 /// An explicit `async` block or the body of an async function.
1401 Async(AsyncGeneratorKind),
1403 /// A generator literal created via a `yield` inside a closure.
1407 impl fmt::Display for GeneratorKind {
1408 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1410 GeneratorKind::Async(k) => fmt::Display::fmt(k, f),
1411 GeneratorKind::Gen => f.write_str("generator"),
1416 /// In the case of a generator created as part of an async construct,
1417 /// which kind of async construct caused it to be created?
1419 /// This helps error messages but is also used to drive coercions in
1420 /// type-checking (see #60424).
1421 #[derive(Clone, PartialEq, Eq, HashStable, RustcEncodable, RustcDecodable, Debug, Copy)]
1422 pub enum AsyncGeneratorKind {
1423 /// An explicit `async` block written by the user.
1426 /// An explicit `async` block written by the user.
1429 /// The `async` block generated as the body of an async function.
1433 impl fmt::Display for AsyncGeneratorKind {
1434 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1435 f.write_str(match self {
1436 AsyncGeneratorKind::Block => "`async` block",
1437 AsyncGeneratorKind::Closure => "`async` closure body",
1438 AsyncGeneratorKind::Fn => "`async fn` body",
1443 #[derive(Copy, Clone, Debug)]
1444 pub enum BodyOwnerKind {
1445 /// Functions and methods.
1451 /// Constants and associated constants.
1454 /// Initializer of a `static` item.
1458 impl BodyOwnerKind {
1459 pub fn is_fn_or_closure(self) -> bool {
1461 BodyOwnerKind::Fn | BodyOwnerKind::Closure => true,
1462 BodyOwnerKind::Const | BodyOwnerKind::Static(_) => false,
1468 pub type Lit = Spanned<LitKind>;
1470 /// A constant (expression) that's not an item or associated item,
1471 /// but needs its own `DefId` for type-checking, const-eval, etc.
1472 /// These are usually found nested inside types (e.g., array lengths)
1473 /// or expressions (e.g., repeat counts), and also used to define
1474 /// explicit discriminant values for enum variants.
1475 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1476 pub struct AnonConst {
1482 #[derive(RustcEncodable, RustcDecodable)]
1486 pub attrs: ThinVec<Attribute>,
1490 // `Expr` is used a lot. Make sure it doesn't unintentionally get bigger.
1491 #[cfg(target_arch = "x86_64")]
1492 static_assert_size!(Expr, 72);
1495 pub fn precedence(&self) -> ExprPrecedence {
1497 ExprKind::Box(_) => ExprPrecedence::Box,
1498 ExprKind::Array(_) => ExprPrecedence::Array,
1499 ExprKind::Call(..) => ExprPrecedence::Call,
1500 ExprKind::MethodCall(..) => ExprPrecedence::MethodCall,
1501 ExprKind::Tup(_) => ExprPrecedence::Tup,
1502 ExprKind::Binary(op, ..) => ExprPrecedence::Binary(op.node.into()),
1503 ExprKind::Unary(..) => ExprPrecedence::Unary,
1504 ExprKind::Lit(_) => ExprPrecedence::Lit,
1505 ExprKind::Type(..) | ExprKind::Cast(..) => ExprPrecedence::Cast,
1506 ExprKind::DropTemps(ref expr, ..) => expr.precedence(),
1507 ExprKind::Loop(..) => ExprPrecedence::Loop,
1508 ExprKind::Match(..) => ExprPrecedence::Match,
1509 ExprKind::Closure(..) => ExprPrecedence::Closure,
1510 ExprKind::Block(..) => ExprPrecedence::Block,
1511 ExprKind::Assign(..) => ExprPrecedence::Assign,
1512 ExprKind::AssignOp(..) => ExprPrecedence::AssignOp,
1513 ExprKind::Field(..) => ExprPrecedence::Field,
1514 ExprKind::Index(..) => ExprPrecedence::Index,
1515 ExprKind::Path(..) => ExprPrecedence::Path,
1516 ExprKind::AddrOf(..) => ExprPrecedence::AddrOf,
1517 ExprKind::Break(..) => ExprPrecedence::Break,
1518 ExprKind::Continue(..) => ExprPrecedence::Continue,
1519 ExprKind::Ret(..) => ExprPrecedence::Ret,
1520 ExprKind::InlineAsm(..) => ExprPrecedence::InlineAsm,
1521 ExprKind::Struct(..) => ExprPrecedence::Struct,
1522 ExprKind::Repeat(..) => ExprPrecedence::Repeat,
1523 ExprKind::Yield(..) => ExprPrecedence::Yield,
1524 ExprKind::Err => ExprPrecedence::Err,
1528 pub fn is_place_expr(&self) -> bool {
1530 ExprKind::Path(QPath::Resolved(_, ref path)) => {
1533 | Res::Def(DefKind::Static, _)
1539 ExprKind::Type(ref e, _) => {
1543 ExprKind::Unary(UnDeref, _) |
1544 ExprKind::Field(..) |
1545 ExprKind::Index(..) => {
1549 // Partially qualified paths in expressions can only legally
1550 // refer to associated items which are always rvalues.
1551 ExprKind::Path(QPath::TypeRelative(..)) |
1553 ExprKind::Call(..) |
1554 ExprKind::MethodCall(..) |
1555 ExprKind::Struct(..) |
1557 ExprKind::Match(..) |
1558 ExprKind::Closure(..) |
1559 ExprKind::Block(..) |
1560 ExprKind::Repeat(..) |
1561 ExprKind::Array(..) |
1562 ExprKind::Break(..) |
1563 ExprKind::Continue(..) |
1565 ExprKind::Loop(..) |
1566 ExprKind::Assign(..) |
1567 ExprKind::InlineAsm(..) |
1568 ExprKind::AssignOp(..) |
1570 ExprKind::Unary(..) |
1572 ExprKind::AddrOf(..) |
1573 ExprKind::Binary(..) |
1574 ExprKind::Yield(..) |
1575 ExprKind::Cast(..) |
1576 ExprKind::DropTemps(..) |
1583 /// If `Self.kind` is `ExprKind::DropTemps(expr)`, drill down until we get a non-`DropTemps`
1584 /// `Expr`. This is used in suggestions to ignore this `ExprKind` as it is semantically
1585 /// silent, only signaling the ownership system. By doing this, suggestions that check the
1586 /// `ExprKind` of any given `Expr` for presentation don't have to care about `DropTemps`
1587 /// beyond remembering to call this function before doing analysis on it.
1588 pub fn peel_drop_temps(&self) -> &Self {
1589 let mut expr = self;
1590 while let ExprKind::DropTemps(inner) = &expr.kind {
1597 impl fmt::Debug for Expr {
1598 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1599 write!(f, "expr({}: {})", self.hir_id,
1600 print::to_string(print::NO_ANN, |s| s.print_expr(self)))
1604 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1606 /// A `box x` expression.
1608 /// An array (e.g., `[a, b, c, d]`).
1609 Array(HirVec<Expr>),
1610 /// A function call.
1612 /// The first field resolves to the function itself (usually an `ExprKind::Path`),
1613 /// and the second field is the list of arguments.
1614 /// This also represents calling the constructor of
1615 /// tuple-like ADTs such as tuple structs and enum variants.
1616 Call(P<Expr>, HirVec<Expr>),
1617 /// A method call (e.g., `x.foo::<'static, Bar, Baz>(a, b, c, d)`).
1619 /// The `PathSegment`/`Span` represent the method name and its generic arguments
1620 /// (within the angle brackets).
1621 /// The first element of the vector of `Expr`s is the expression that evaluates
1622 /// to the object on which the method is being called on (the receiver),
1623 /// and the remaining elements are the rest of the arguments.
1624 /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as
1625 /// `ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d])`.
1626 MethodCall(P<PathSegment>, Span, HirVec<Expr>),
1627 /// A tuple (e.g., `(a, b, c, d)`).
1629 /// A binary operation (e.g., `a + b`, `a * b`).
1630 Binary(BinOp, P<Expr>, P<Expr>),
1631 /// A unary operation (e.g., `!x`, `*x`).
1632 Unary(UnOp, P<Expr>),
1633 /// A literal (e.g., `1`, `"foo"`).
1635 /// A cast (e.g., `foo as f64`).
1636 Cast(P<Expr>, P<Ty>),
1637 /// A type reference (e.g., `Foo`).
1638 Type(P<Expr>, P<Ty>),
1639 /// Wraps the expression in a terminating scope.
1640 /// This makes it semantically equivalent to `{ let _t = expr; _t }`.
1642 /// This construct only exists to tweak the drop order in HIR lowering.
1643 /// An example of that is the desugaring of `for` loops.
1645 /// A conditionless loop (can be exited with `break`, `continue`, or `return`).
1647 /// I.e., `'label: loop { <block> }`.
1648 Loop(P<Block>, Option<Label>, LoopSource),
1649 /// A `match` block, with a source that indicates whether or not it is
1650 /// the result of a desugaring, and if so, which kind.
1651 Match(P<Expr>, HirVec<Arm>, MatchSource),
1652 /// A closure (e.g., `move |a, b, c| {a + b + c}`).
1654 /// The `Span` is the argument block `|...|`.
1656 /// This may also be a generator literal or an `async block` as indicated by the
1657 /// `Option<GeneratorMovability>`.
1658 Closure(CaptureClause, P<FnDecl>, BodyId, Span, Option<GeneratorMovability>),
1659 /// A block (e.g., `'label: { ... }`).
1660 Block(P<Block>, Option<Label>),
1662 /// An assignment (e.g., `a = foo()`).
1663 Assign(P<Expr>, P<Expr>),
1664 /// An assignment with an operator.
1667 AssignOp(BinOp, P<Expr>, P<Expr>),
1668 /// Access of a named (e.g., `obj.foo`) or unnamed (e.g., `obj.0`) struct or tuple field.
1669 Field(P<Expr>, Ident),
1670 /// An indexing operation (`foo[2]`).
1671 Index(P<Expr>, P<Expr>),
1673 /// Path to a definition, possibly containing lifetime or type parameters.
1676 /// A referencing operation (i.e., `&a` or `&mut a`).
1677 AddrOf(Mutability, P<Expr>),
1678 /// A `break`, with an optional label to break.
1679 Break(Destination, Option<P<Expr>>),
1680 /// A `continue`, with an optional label.
1681 Continue(Destination),
1682 /// A `return`, with an optional value to be returned.
1683 Ret(Option<P<Expr>>),
1685 /// Inline assembly (from `asm!`), with its outputs and inputs.
1686 InlineAsm(P<InlineAsm>, HirVec<Expr>, HirVec<Expr>),
1688 /// A struct or struct-like variant literal expression.
1690 /// E.g., `Foo {x: 1, y: 2}`, or `Foo {x: 1, .. base}`,
1691 /// where `base` is the `Option<Expr>`.
1692 Struct(P<QPath>, HirVec<Field>, Option<P<Expr>>),
1694 /// An array literal constructed from one repeated element.
1696 /// E.g., `[1; 5]`. The first expression is the element
1697 /// to be repeated; the second is the number of times to repeat it.
1698 Repeat(P<Expr>, AnonConst),
1700 /// A suspension point for generators (i.e., `yield <expr>`).
1701 Yield(P<Expr>, YieldSource),
1703 /// A placeholder for an expression that wasn't syntactically well formed in some way.
1707 /// Represents an optionally `Self`-qualified value/type path or associated extension.
1708 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1710 /// Path to a definition, optionally "fully-qualified" with a `Self`
1711 /// type, if the path points to an associated item in a trait.
1713 /// E.g., an unqualified path like `Clone::clone` has `None` for `Self`,
1714 /// while `<Vec<T> as Clone>::clone` has `Some(Vec<T>)` for `Self`,
1715 /// even though they both have the same two-segment `Clone::clone` `Path`.
1716 Resolved(Option<P<Ty>>, P<Path>),
1718 /// Type-related paths (e.g., `<T>::default` or `<T>::Output`).
1719 /// Will be resolved by type-checking to an associated item.
1721 /// UFCS source paths can desugar into this, with `Vec::new` turning into
1722 /// `<Vec>::new`, and `T::X::Y::method` into `<<<T>::X>::Y>::method`,
1723 /// the `X` and `Y` nodes each being a `TyKind::Path(QPath::TypeRelative(..))`.
1724 TypeRelative(P<Ty>, P<PathSegment>)
1727 /// Hints at the original code for a let statement.
1728 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
1729 pub enum LocalSource {
1730 /// A `match _ { .. }`.
1732 /// A desugared `for _ in _ { .. }` loop.
1734 /// When lowering async functions, we create locals within the `async move` so that
1735 /// all parameters are dropped after the future is polled.
1737 /// ```ignore (pseudo-Rust)
1738 /// async fn foo(<pattern> @ x: Type) {
1740 /// let <pattern> = x;
1745 /// A desugared `<expr>.await`.
1749 /// Hints at the original code for a `match _ { .. }`.
1750 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, HashStable)]
1751 pub enum MatchSource {
1752 /// A `match _ { .. }`.
1754 /// An `if _ { .. }` (optionally with `else { .. }`).
1756 contains_else_clause: bool,
1758 /// An `if let _ = _ { .. }` (optionally with `else { .. }`).
1760 contains_else_clause: bool,
1762 /// A `while _ { .. }` (which was desugared to a `loop { match _ { .. } }`).
1764 /// A `while let _ = _ { .. }` (which was desugared to a
1765 /// `loop { match _ { .. } }`).
1767 /// A desugared `for _ in _ { .. }` loop.
1769 /// A desugared `?` operator.
1771 /// A desugared `<expr>.await`.
1775 /// The loop type that yielded an `ExprKind::Loop`.
1776 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
1777 pub enum LoopSource {
1778 /// A `loop { .. }` loop.
1780 /// A `while _ { .. }` loop.
1782 /// A `while let _ = _ { .. }` loop.
1784 /// A `for _ in _ { .. }` loop.
1789 pub fn name(self) -> &'static str {
1791 LoopSource::Loop => "loop",
1792 LoopSource::While => "while",
1793 LoopSource::WhileLet => "while let",
1794 LoopSource::ForLoop => "for",
1799 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
1800 pub enum LoopIdError {
1802 UnlabeledCfInWhileCondition,
1806 impl fmt::Display for LoopIdError {
1807 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1808 f.write_str(match self {
1809 LoopIdError::OutsideLoopScope => "not inside loop scope",
1810 LoopIdError::UnlabeledCfInWhileCondition =>
1811 "unlabeled control flow (break or continue) in while condition",
1812 LoopIdError::UnresolvedLabel => "label not found",
1817 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
1818 pub struct Destination {
1819 // This is `Some(_)` iff there is an explicit user-specified `label
1820 pub label: Option<Label>,
1822 // These errors are caught and then reported during the diagnostics pass in
1823 // librustc_passes/loops.rs
1824 pub target_id: Result<HirId, LoopIdError>,
1827 /// Whether a generator contains self-references, causing it to be `!Unpin`.
1828 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, HashStable,
1829 RustcEncodable, RustcDecodable, Hash, Debug)]
1830 pub enum GeneratorMovability {
1831 /// May contain self-references, `!Unpin`.
1834 /// Must not contain self-references, `Unpin`.
1838 /// The yield kind that caused an `ExprKind::Yield`.
1839 #[derive(Copy, Clone, PartialEq, Eq, Debug, RustcEncodable, RustcDecodable, HashStable)]
1840 pub enum YieldSource {
1841 /// An `<expr>.await`.
1843 /// A plain `yield`.
1847 impl fmt::Display for YieldSource {
1848 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1849 f.write_str(match self {
1850 YieldSource::Await => "`await`",
1851 YieldSource::Yield => "`yield`",
1856 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
1857 pub enum CaptureClause {
1862 // N.B., if you change this, you'll probably want to change the corresponding
1863 // type structure in middle/ty.rs as well.
1864 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1867 pub mutbl: Mutability,
1870 /// Represents a method's signature in a trait declaration or implementation.
1871 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1872 pub struct MethodSig {
1873 pub header: FnHeader,
1874 pub decl: P<FnDecl>,
1877 // The bodies for items are stored "out of line", in a separate
1878 // hashmap in the `Crate`. Here we just record the node-id of the item
1879 // so it can fetched later.
1880 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Debug)]
1881 pub struct TraitItemId {
1885 /// Represents an item declaration within a trait declaration,
1886 /// possibly including a default implementation. A trait item is
1887 /// either required (meaning it doesn't have an implementation, just a
1888 /// signature) or provided (meaning it has a default implementation).
1889 #[derive(RustcEncodable, RustcDecodable, Debug)]
1890 pub struct TraitItem {
1893 pub attrs: HirVec<Attribute>,
1894 pub generics: Generics,
1895 pub kind: TraitItemKind,
1899 /// Represents a trait method's body (or just argument names).
1900 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1901 pub enum TraitMethod {
1902 /// No default body in the trait, just a signature.
1903 Required(HirVec<Ident>),
1905 /// Both signature and body are provided in the trait.
1909 /// Represents a trait method or associated constant or type
1910 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1911 pub enum TraitItemKind {
1912 /// An associated constant with an optional value (otherwise `impl`s must contain a value).
1913 Const(P<Ty>, Option<BodyId>),
1914 /// A method with an optional body.
1915 Method(MethodSig, TraitMethod),
1916 /// An associated type with (possibly empty) bounds and optional concrete
1918 Type(GenericBounds, Option<P<Ty>>),
1921 // The bodies for items are stored "out of line", in a separate
1922 // hashmap in the `Crate`. Here we just record the node-id of the item
1923 // so it can fetched later.
1924 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Debug)]
1925 pub struct ImplItemId {
1929 /// Represents anything within an `impl` block.
1930 #[derive(RustcEncodable, RustcDecodable, Debug)]
1931 pub struct ImplItem {
1934 pub vis: Visibility,
1935 pub defaultness: Defaultness,
1936 pub attrs: HirVec<Attribute>,
1937 pub generics: Generics,
1938 pub kind: ImplItemKind,
1942 /// Represents various kinds of content within an `impl`.
1943 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1944 pub enum ImplItemKind {
1945 /// An associated constant of the given type, set to the constant result
1946 /// of the expression.
1947 Const(P<Ty>, BodyId),
1948 /// A method implementation with the given signature and body.
1949 Method(MethodSig, BodyId),
1950 /// An associated type.
1952 /// An associated `type = impl Trait`.
1953 OpaqueTy(GenericBounds),
1956 /// Bind a type to an associated type (i.e., `A = Foo`).
1958 /// Bindings like `A: Debug` are represented as a special type `A =
1959 /// $::Debug` that is understood by the astconv code.
1961 /// FIXME(alexreg) -- why have a separate type for the binding case,
1962 /// wouldn't it be better to make the `ty` field an enum like:
1965 /// enum TypeBindingKind {
1970 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1971 pub struct TypeBinding {
1973 #[stable_hasher(project(name))]
1975 pub kind: TypeBindingKind,
1979 // Represents the two kinds of type bindings.
1980 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
1981 pub enum TypeBindingKind {
1982 /// E.g., `Foo<Bar: Send>`.
1984 bounds: HirVec<GenericBound>,
1986 /// E.g., `Foo<Bar = ()>`.
1993 pub fn ty(&self) -> &Ty {
1995 TypeBindingKind::Equality { ref ty } => ty,
1996 _ => bug!("expected equality type binding for parenthesized generic args"),
2001 #[derive(RustcEncodable, RustcDecodable)]
2008 impl fmt::Debug for Ty {
2009 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2010 write!(f, "type({})",
2011 print::to_string(print::NO_ANN, |s| s.print_type(self)))
2015 /// Not represented directly in the AST; referred to by name through a `ty_path`.
2016 #[derive(Copy, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug, HashStable)]
2026 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2027 pub struct BareFnTy {
2028 pub unsafety: Unsafety,
2030 pub generic_params: HirVec<GenericParam>,
2031 pub decl: P<FnDecl>,
2032 pub param_names: HirVec<Ident>,
2035 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2036 pub struct OpaqueTy {
2037 pub generics: Generics,
2038 pub bounds: GenericBounds,
2039 pub impl_trait_fn: Option<DefId>,
2040 pub origin: OpaqueTyOrigin,
2043 /// From whence the opaque type came.
2044 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
2045 pub enum OpaqueTyOrigin {
2046 /// `type Foo = impl Trait;`
2054 /// The various kinds of types recognized by the compiler.
2055 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2057 /// A variable length slice (i.e., `[T]`).
2059 /// A fixed length array (i.e., `[T; n]`).
2060 Array(P<Ty>, AnonConst),
2061 /// A raw pointer (i.e., `*const T` or `*mut T`).
2063 /// A reference (i.e., `&'a T` or `&'a mut T`).
2064 Rptr(Lifetime, MutTy),
2065 /// A bare function (e.g., `fn(usize) -> bool`).
2066 BareFn(P<BareFnTy>),
2067 /// The never type (`!`).
2069 /// A tuple (`(A, B, C, D, ...)`).
2071 /// A path to a type definition (`module::module::...::Type`), or an
2072 /// associated type (e.g., `<Vec<T> as Trait>::Type` or `<T>::Target`).
2074 /// Type parameters may be stored in each `PathSegment`.
2076 /// A type definition itself. This is currently only used for the `type Foo = impl Trait`
2077 /// item that `impl Trait` in return position desugars to.
2079 /// The generic argument list contains the lifetimes (and in the future possibly parameters)
2080 /// that are actually bound on the `impl Trait`.
2081 Def(ItemId, HirVec<GenericArg>),
2082 /// A trait object type `Bound1 + Bound2 + Bound3`
2083 /// where `Bound` is a trait or a lifetime.
2084 TraitObject(HirVec<PolyTraitRef>, Lifetime),
2087 /// `TyKind::Infer` means the type should be inferred instead of it having been
2088 /// specified. This can appear anywhere in a type.
2090 /// Placeholder for a type that has failed to be defined.
2094 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
2095 pub struct InlineAsmOutput {
2096 pub constraint: Symbol,
2098 pub is_indirect: bool,
2102 // NOTE(eddyb) This is used within MIR as well, so unlike the rest of the HIR,
2103 // it needs to be `Clone` and use plain `Vec<T>` instead of `HirVec<T>`.
2104 #[derive(Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
2105 pub struct InlineAsm {
2107 pub asm_str_style: StrStyle,
2108 pub outputs: Vec<InlineAsmOutput>,
2109 pub inputs: Vec<Symbol>,
2110 pub clobbers: Vec<Symbol>,
2112 pub alignstack: bool,
2113 pub dialect: AsmDialect,
2116 /// Represents a parameter in a function header.
2117 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2119 pub attrs: HirVec<Attribute>,
2125 /// Represents the header (not the body) of a function declaration.
2126 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2128 /// The types of the function's parameters.
2130 /// Additional argument data is stored in the function's [body](Body::parameters).
2131 pub inputs: HirVec<Ty>,
2132 pub output: FunctionRetTy,
2133 pub c_variadic: bool,
2134 /// Does the function have an implicit self?
2135 pub implicit_self: ImplicitSelfKind,
2138 /// Represents what type of implicit self a function has, if any.
2139 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
2140 pub enum ImplicitSelfKind {
2141 /// Represents a `fn x(self);`.
2143 /// Represents a `fn x(mut self);`.
2145 /// Represents a `fn x(&self);`.
2147 /// Represents a `fn x(&mut self);`.
2149 /// Represents when a function does not have a self argument or
2150 /// when a function has a `self: X` argument.
2154 impl ImplicitSelfKind {
2155 /// Does this represent an implicit self?
2156 pub fn has_implicit_self(&self) -> bool {
2158 ImplicitSelfKind::None => false,
2164 /// Is the trait definition an auto trait?
2165 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
2171 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, HashStable,
2172 Ord, RustcEncodable, RustcDecodable, Debug)]
2178 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, HashStable,
2179 RustcEncodable, RustcDecodable, Hash, Debug)]
2186 pub fn prefix_str(&self) -> &'static str {
2188 Unsafety::Unsafe => "unsafe ",
2189 Unsafety::Normal => "",
2194 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
2195 pub enum Constness {
2200 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
2201 pub enum Defaultness {
2202 Default { has_value: bool },
2207 pub fn has_value(&self) -> bool {
2209 Defaultness::Default { has_value, .. } => has_value,
2210 Defaultness::Final => true,
2214 pub fn is_final(&self) -> bool {
2215 *self == Defaultness::Final
2218 pub fn is_default(&self) -> bool {
2220 Defaultness::Default { .. } => true,
2226 impl fmt::Display for Unsafety {
2227 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2228 f.write_str(match self {
2229 Unsafety::Normal => "normal",
2230 Unsafety::Unsafe => "unsafe",
2235 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, HashStable)]
2236 pub enum ImplPolarity {
2237 /// `impl Trait for Type`
2239 /// `impl !Trait for Type`
2243 impl fmt::Debug for ImplPolarity {
2244 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2245 f.write_str(match self {
2246 ImplPolarity::Positive => "positive",
2247 ImplPolarity::Negative => "negative",
2253 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2254 pub enum FunctionRetTy {
2255 /// Return type is not specified.
2257 /// Functions default to `()` and
2258 /// closures default to inference. Span points to where return
2259 /// type would be inserted.
2260 DefaultReturn(Span),
2261 /// Everything else.
2265 impl fmt::Display for FunctionRetTy {
2266 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
2268 Return(ref ty) => print::to_string(print::NO_ANN, |s| s.print_type(ty)).fmt(f),
2269 DefaultReturn(_) => "()".fmt(f),
2274 impl FunctionRetTy {
2275 pub fn span(&self) -> Span {
2277 DefaultReturn(span) => span,
2278 Return(ref ty) => ty.span,
2283 #[derive(RustcEncodable, RustcDecodable, Debug)]
2285 /// A span from the first token past `{` to the last token until `}`.
2286 /// For `mod foo;`, the inner span ranges from the first token
2287 /// to the last token in the external file.
2289 pub item_ids: HirVec<ItemId>,
2292 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2293 pub struct ForeignMod {
2295 pub items: HirVec<ForeignItem>,
2298 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2299 pub struct GlobalAsm {
2303 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2304 pub struct EnumDef {
2305 pub variants: HirVec<Variant>,
2308 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2309 pub struct Variant {
2310 /// Name of the variant.
2311 #[stable_hasher(project(name))]
2313 /// Attributes of the variant.
2314 pub attrs: HirVec<Attribute>,
2315 /// Id of the variant (not the constructor, see `VariantData::ctor_hir_id()`).
2317 /// Fields and constructor id of the variant.
2318 pub data: VariantData,
2319 /// Explicit discriminant (e.g., `Foo = 1`).
2320 pub disr_expr: Option<AnonConst>,
2325 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
2327 /// One import, e.g., `use foo::bar` or `use foo::bar as baz`.
2328 /// Also produced for each element of a list `use`, e.g.
2329 /// `use foo::{a, b}` lowers to `use foo::a; use foo::b;`.
2332 /// Glob import, e.g., `use foo::*`.
2335 /// Degenerate list import, e.g., `use foo::{a, b}` produces
2336 /// an additional `use foo::{}` for performing checks such as
2337 /// unstable feature gating. May be removed in the future.
2341 /// References to traits in impls.
2343 /// `resolve` maps each `TraitRef`'s `ref_id` to its defining trait; that's all
2344 /// that the `ref_id` is for. Note that `ref_id`'s value is not the `HirId` of the
2345 /// trait being referred to but just a unique `HirId` that serves as a key
2346 /// within the resolution map.
2347 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2348 pub struct TraitRef {
2350 // Don't hash the `ref_id`. It is tracked via the thing it is used to access.
2351 #[stable_hasher(ignore)]
2352 pub hir_ref_id: HirId,
2356 /// Gets the `DefId` of the referenced trait. It _must_ actually be a trait or trait alias.
2357 pub fn trait_def_id(&self) -> DefId {
2358 match self.path.res {
2359 Res::Def(DefKind::Trait, did) => did,
2360 Res::Def(DefKind::TraitAlias, did) => did,
2364 _ => unreachable!(),
2369 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2370 pub struct PolyTraitRef {
2371 /// The `'a` in `<'a> Foo<&'a T>`.
2372 pub bound_generic_params: HirVec<GenericParam>,
2374 /// The `Foo<&'a T>` in `<'a> Foo<&'a T>`.
2375 pub trait_ref: TraitRef,
2380 pub type Visibility = Spanned<VisibilityKind>;
2382 #[derive(RustcEncodable, RustcDecodable, Debug)]
2383 pub enum VisibilityKind {
2386 Restricted { path: P<Path>, hir_id: HirId },
2390 impl VisibilityKind {
2391 pub fn is_pub(&self) -> bool {
2393 VisibilityKind::Public => true,
2398 pub fn is_pub_restricted(&self) -> bool {
2400 VisibilityKind::Public |
2401 VisibilityKind::Inherited => false,
2402 VisibilityKind::Crate(..) |
2403 VisibilityKind::Restricted { .. } => true,
2407 pub fn descr(&self) -> &'static str {
2409 VisibilityKind::Public => "public",
2410 VisibilityKind::Inherited => "private",
2411 VisibilityKind::Crate(..) => "crate-visible",
2412 VisibilityKind::Restricted { .. } => "restricted",
2417 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2418 pub struct StructField {
2420 #[stable_hasher(project(name))]
2422 pub vis: Visibility,
2425 pub attrs: HirVec<Attribute>,
2429 // Still necessary in couple of places
2430 pub fn is_positional(&self) -> bool {
2431 let first = self.ident.as_str().as_bytes()[0];
2432 first >= b'0' && first <= b'9'
2436 /// Fields and constructor IDs of enum variants and structs.
2437 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2438 pub enum VariantData {
2439 /// A struct variant.
2441 /// E.g., `Bar { .. }` as in `enum Foo { Bar { .. } }`.
2442 Struct(HirVec<StructField>, /* recovered */ bool),
2443 /// A tuple variant.
2445 /// E.g., `Bar(..)` as in `enum Foo { Bar(..) }`.
2446 Tuple(HirVec<StructField>, HirId),
2449 /// E.g., `Bar = ..` as in `enum Foo { Bar = .. }`.
2454 /// Return the fields of this variant.
2455 pub fn fields(&self) -> &[StructField] {
2457 VariantData::Struct(ref fields, ..) | VariantData::Tuple(ref fields, ..) => fields,
2462 /// Return the `HirId` of this variant's constructor, if it has one.
2463 pub fn ctor_hir_id(&self) -> Option<HirId> {
2465 VariantData::Struct(_, _) => None,
2466 VariantData::Tuple(_, hir_id) | VariantData::Unit(hir_id) => Some(hir_id),
2471 // The bodies for items are stored "out of line", in a separate
2472 // hashmap in the `Crate`. Here we just record the node-id of the item
2473 // so it can fetched later.
2474 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug)]
2481 /// The name might be a dummy name in case of anonymous items
2482 #[derive(RustcEncodable, RustcDecodable, Debug)]
2486 pub attrs: HirVec<Attribute>,
2488 pub vis: Visibility,
2492 #[derive(Copy, Clone, RustcEncodable, RustcDecodable, Debug, HashStable)]
2493 pub struct FnHeader {
2494 pub unsafety: Unsafety,
2495 pub constness: Constness,
2496 pub asyncness: IsAsync,
2501 pub fn is_const(&self) -> bool {
2502 match &self.constness {
2503 Constness::Const => true,
2509 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2511 /// An `extern crate` item, with optional *original* crate name if the crate was renamed.
2513 /// E.g., `extern crate foo` or `extern crate foo_bar as foo`.
2514 ExternCrate(Option<Name>),
2516 /// `use foo::bar::*;` or `use foo::bar::baz as quux;`
2520 /// `use foo::bar::baz;` (with `as baz` implicitly on the right).
2521 Use(P<Path>, UseKind),
2523 /// A `static` item.
2524 Static(P<Ty>, Mutability, BodyId),
2526 Const(P<Ty>, BodyId),
2527 /// A function declaration.
2528 Fn(P<FnDecl>, FnHeader, Generics, BodyId),
2531 /// An external module, e.g. `extern { .. }`.
2532 ForeignMod(ForeignMod),
2533 /// Module-level inline assembly (from `global_asm!`).
2534 GlobalAsm(P<GlobalAsm>),
2535 /// A type alias, e.g., `type Foo = Bar<u8>`.
2536 TyAlias(P<Ty>, Generics),
2537 /// An opaque `impl Trait` type alias, e.g., `type Foo = impl Bar;`.
2539 /// An enum definition, e.g., `enum Foo<A, B> {C<A>, D<B>}`.
2540 Enum(EnumDef, Generics),
2541 /// A struct definition, e.g., `struct Foo<A> {x: A}`.
2542 Struct(VariantData, Generics),
2543 /// A union definition, e.g., `union Foo<A, B> {x: A, y: B}`.
2544 Union(VariantData, Generics),
2545 /// A trait definition.
2546 Trait(IsAuto, Unsafety, Generics, GenericBounds, HirVec<TraitItemRef>),
2548 TraitAlias(Generics, GenericBounds),
2550 /// An implementation, e.g., `impl<A> Trait for Foo { .. }`.
2555 Option<TraitRef>, // (optional) trait this impl implements
2557 HirVec<ImplItemRef>),
2561 pub fn descriptive_variant(&self) -> &str {
2563 ItemKind::ExternCrate(..) => "extern crate",
2564 ItemKind::Use(..) => "use",
2565 ItemKind::Static(..) => "static item",
2566 ItemKind::Const(..) => "constant item",
2567 ItemKind::Fn(..) => "function",
2568 ItemKind::Mod(..) => "module",
2569 ItemKind::ForeignMod(..) => "foreign module",
2570 ItemKind::GlobalAsm(..) => "global asm",
2571 ItemKind::TyAlias(..) => "type alias",
2572 ItemKind::OpaqueTy(..) => "opaque type",
2573 ItemKind::Enum(..) => "enum",
2574 ItemKind::Struct(..) => "struct",
2575 ItemKind::Union(..) => "union",
2576 ItemKind::Trait(..) => "trait",
2577 ItemKind::TraitAlias(..) => "trait alias",
2578 ItemKind::Impl(..) => "impl",
2582 pub fn adt_kind(&self) -> Option<AdtKind> {
2584 ItemKind::Struct(..) => Some(AdtKind::Struct),
2585 ItemKind::Union(..) => Some(AdtKind::Union),
2586 ItemKind::Enum(..) => Some(AdtKind::Enum),
2591 pub fn generics(&self) -> Option<&Generics> {
2593 ItemKind::Fn(_, _, ref generics, _) |
2594 ItemKind::TyAlias(_, ref generics) |
2595 ItemKind::OpaqueTy(OpaqueTy { ref generics, impl_trait_fn: None, .. }) |
2596 ItemKind::Enum(_, ref generics) |
2597 ItemKind::Struct(_, ref generics) |
2598 ItemKind::Union(_, ref generics) |
2599 ItemKind::Trait(_, _, ref generics, _, _) |
2600 ItemKind::Impl(_, _, _, ref generics, _, _, _)=> generics,
2606 /// A reference from an trait to one of its associated items. This
2607 /// contains the item's id, naturally, but also the item's name and
2608 /// some other high-level details (like whether it is an associated
2609 /// type or method, and whether it is public). This allows other
2610 /// passes to find the impl they want without loading the ID (which
2611 /// means fewer edges in the incremental compilation graph).
2612 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2613 pub struct TraitItemRef {
2614 pub id: TraitItemId,
2615 #[stable_hasher(project(name))]
2617 pub kind: AssocItemKind,
2619 pub defaultness: Defaultness,
2622 /// A reference from an impl to one of its associated items. This
2623 /// contains the item's ID, naturally, but also the item's name and
2624 /// some other high-level details (like whether it is an associated
2625 /// type or method, and whether it is public). This allows other
2626 /// passes to find the impl they want without loading the ID (which
2627 /// means fewer edges in the incremental compilation graph).
2628 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2629 pub struct ImplItemRef {
2631 #[stable_hasher(project(name))]
2633 pub kind: AssocItemKind,
2635 pub vis: Visibility,
2636 pub defaultness: Defaultness,
2639 #[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, Debug, HashStable)]
2640 pub enum AssocItemKind {
2642 Method { has_self: bool },
2647 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2648 pub struct ForeignItem {
2649 #[stable_hasher(project(name))]
2651 pub attrs: HirVec<Attribute>,
2652 pub kind: ForeignItemKind,
2655 pub vis: Visibility,
2658 /// An item within an `extern` block.
2659 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
2660 pub enum ForeignItemKind {
2661 /// A foreign function.
2662 Fn(P<FnDecl>, HirVec<Ident>, Generics),
2663 /// A foreign static item (`static ext: u8`).
2664 Static(P<Ty>, Mutability),
2669 impl ForeignItemKind {
2670 pub fn descriptive_variant(&self) -> &str {
2672 ForeignItemKind::Fn(..) => "foreign function",
2673 ForeignItemKind::Static(..) => "foreign static item",
2674 ForeignItemKind::Type => "foreign type",
2679 /// A variable captured by a closure.
2680 #[derive(Debug, Copy, Clone, RustcEncodable, RustcDecodable, HashStable)]
2682 // First span where it is accessed (there can be multiple).
2686 pub type CaptureModeMap = NodeMap<CaptureClause>;
2688 // The TraitCandidate's import_ids is empty if the trait is defined in the same module, and
2689 // has length > 0 if the trait is found through an chain of imports, starting with the
2690 // import/use statement in the scope where the trait is used.
2691 #[derive(Clone, Debug)]
2692 pub struct TraitCandidate {
2694 pub import_ids: SmallVec<[NodeId; 1]>,
2697 // Trait method resolution
2698 pub type TraitMap = NodeMap<Vec<TraitCandidate>>;
2700 // Map from the NodeId of a glob import to a list of items which are actually
2702 pub type GlobMap = NodeMap<FxHashSet<Name>>;
2704 pub fn provide(providers: &mut Providers<'_>) {
2705 check_attr::provide(providers);
2706 map::provide(providers);
2707 upvars::provide(providers);
2710 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
2711 pub struct CodegenFnAttrs {
2712 pub flags: CodegenFnAttrFlags,
2713 /// Parsed representation of the `#[inline]` attribute
2714 pub inline: InlineAttr,
2715 /// Parsed representation of the `#[optimize]` attribute
2716 pub optimize: OptimizeAttr,
2717 /// The `#[export_name = "..."]` attribute, indicating a custom symbol a
2718 /// function should be exported under
2719 pub export_name: Option<Symbol>,
2720 /// The `#[link_name = "..."]` attribute, indicating a custom symbol an
2721 /// imported function should be imported as. Note that `export_name`
2722 /// probably isn't set when this is set, this is for foreign items while
2723 /// `#[export_name]` is for Rust-defined functions.
2724 pub link_name: Option<Symbol>,
2725 /// The `#[link_ordinal = "..."]` attribute, indicating an ordinal an
2726 /// imported function has in the dynamic library. Note that this must not
2727 /// be set when `link_name` is set. This is for foreign items with the
2728 /// "raw-dylib" kind.
2729 pub link_ordinal: Option<usize>,
2730 /// The `#[target_feature(enable = "...")]` attribute and the enabled
2731 /// features (only enabled features are supported right now).
2732 pub target_features: Vec<Symbol>,
2733 /// The `#[linkage = "..."]` attribute and the value we found.
2734 pub linkage: Option<Linkage>,
2735 /// The `#[link_section = "..."]` attribute, or what executable section this
2736 /// should be placed in.
2737 pub link_section: Option<Symbol>,
2741 #[derive(RustcEncodable, RustcDecodable, HashStable)]
2742 pub struct CodegenFnAttrFlags: u32 {
2743 /// `#[cold]`: a hint to LLVM that this function, when called, is never on
2745 const COLD = 1 << 0;
2746 /// `#[rustc_allocator]`: a hint to LLVM that the pointer returned from this
2747 /// function is never null.
2748 const ALLOCATOR = 1 << 1;
2749 /// `#[unwind]`: an indicator that this function may unwind despite what
2750 /// its ABI signature may otherwise imply.
2751 const UNWIND = 1 << 2;
2752 /// `#[rust_allocator_nounwind]`, an indicator that an imported FFI
2753 /// function will never unwind. Probably obsolete by recent changes with
2754 /// #[unwind], but hasn't been removed/migrated yet
2755 const RUSTC_ALLOCATOR_NOUNWIND = 1 << 3;
2756 /// `#[naked]`: an indicator to LLVM that no function prologue/epilogue
2757 /// should be generated.
2758 const NAKED = 1 << 4;
2759 /// `#[no_mangle]`: an indicator that the function's name should be the same
2761 const NO_MANGLE = 1 << 5;
2762 /// `#[rustc_std_internal_symbol]`: an indicator that this symbol is a
2763 /// "weird symbol" for the standard library in that it has slightly
2764 /// different linkage, visibility, and reachability rules.
2765 const RUSTC_STD_INTERNAL_SYMBOL = 1 << 6;
2766 /// `#[no_debug]`: an indicator that no debugging information should be
2767 /// generated for this function by LLVM.
2768 const NO_DEBUG = 1 << 7;
2769 /// `#[thread_local]`: indicates a static is actually a thread local
2771 const THREAD_LOCAL = 1 << 8;
2772 /// `#[used]`: indicates that LLVM can't eliminate this function (but the
2774 const USED = 1 << 9;
2775 /// `#[ffi_returns_twice]`, indicates that an extern function can return
2777 const FFI_RETURNS_TWICE = 1 << 10;
2778 /// `#[track_caller]`: allow access to the caller location
2779 const TRACK_CALLER = 1 << 11;
2783 impl CodegenFnAttrs {
2784 pub fn new() -> CodegenFnAttrs {
2786 flags: CodegenFnAttrFlags::empty(),
2787 inline: InlineAttr::None,
2788 optimize: OptimizeAttr::None,
2792 target_features: vec![],
2798 /// Returns `true` if `#[inline]` or `#[inline(always)]` is present.
2799 pub fn requests_inline(&self) -> bool {
2801 InlineAttr::Hint | InlineAttr::Always => true,
2802 InlineAttr::None | InlineAttr::Never => false,
2806 /// Returns `true` if it looks like this symbol needs to be exported, for example:
2808 /// * `#[no_mangle]` is present
2809 /// * `#[export_name(...)]` is present
2810 /// * `#[linkage]` is present
2811 pub fn contains_extern_indicator(&self) -> bool {
2812 self.flags.contains(CodegenFnAttrFlags::NO_MANGLE) ||
2813 self.export_name.is_some() ||
2814 match self.linkage {
2815 // These are private, so make sure we don't try to consider
2818 Some(Linkage::Internal) |
2819 Some(Linkage::Private) => false,
2825 #[derive(Copy, Clone, Debug)]
2826 pub enum Node<'hir> {
2829 ForeignItem(&'hir ForeignItem),
2830 TraitItem(&'hir TraitItem),
2831 ImplItem(&'hir ImplItem),
2832 Variant(&'hir Variant),
2833 Field(&'hir StructField),
2834 AnonConst(&'hir AnonConst),
2837 PathSegment(&'hir PathSegment),
2839 TraitRef(&'hir TraitRef),
2845 MacroDef(&'hir MacroDef),
2847 /// `Ctor` refers to the constructor of an enum variant or struct. Only tuple or unit variants
2848 /// with synthesized constructors.
2849 Ctor(&'hir VariantData),
2851 Lifetime(&'hir Lifetime),
2852 GenericParam(&'hir GenericParam),
2853 Visibility(&'hir Visibility),
2859 pub fn ident(&self) -> Option<Ident> {
2861 Node::TraitItem(TraitItem { ident, .. }) |
2862 Node::ImplItem(ImplItem { ident, .. }) |
2863 Node::ForeignItem(ForeignItem { ident, .. }) |
2864 Node::Item(Item { ident, .. }) => Some(*ident),