1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 pub use self::ImplOrTraitItemId
::*;
12 pub use self::ClosureKind
::*;
13 pub use self::Variance
::*;
14 pub use self::DtorKind
::*;
15 pub use self::ImplOrTraitItemContainer
::*;
16 pub use self::BorrowKind
::*;
17 pub use self::ImplOrTraitItem
::*;
18 pub use self::IntVarValue
::*;
19 pub use self::LvaluePreference
::*;
20 pub use self::fold
::TypeFoldable
;
22 use dep_graph
::{self, DepNode}
;
23 use front
::map
as ast_map
;
24 use front
::map
::LinkedPath
;
26 use middle
::cstore
::{self, CrateStore, LOCAL_CRATE}
;
27 use middle
::def
::{self, Def, ExportMap}
;
28 use middle
::def_id
::DefId
;
29 use middle
::lang_items
::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangItem}
;
30 use middle
::region
::{CodeExtent}
;
31 use middle
::subst
::{self, Subst, Substs, VecPerParamSpace}
;
34 use middle
::ty
::fold
::TypeFolder
;
35 use middle
::ty
::walk
::TypeWalker
;
36 use util
::common
::MemoizationMap
;
37 use util
::nodemap
::{NodeMap, NodeSet}
;
38 use util
::nodemap
::FnvHashMap
;
40 use serialize
::{Encodable, Encoder, Decodable, Decoder}
;
41 use std
::borrow
::{Borrow, Cow}
;
43 use std
::hash
::{Hash, Hasher}
;
47 use std
::vec
::IntoIter
;
48 use std
::collections
::{HashMap, HashSet}
;
49 use syntax
::ast
::{self, CrateNum, Name, NodeId}
;
50 use syntax
::attr
::{self, AttrMetaMethods}
;
51 use syntax
::codemap
::{DUMMY_SP, Span}
;
52 use syntax
::parse
::token
::InternedString
;
55 use rustc_front
::hir
::{ItemImpl, ItemTrait, PatKind}
;
56 use rustc_front
::intravisit
::Visitor
;
58 pub use self::sty
::{Binder, DebruijnIndex}
;
59 pub use self::sty
::{BuiltinBound, BuiltinBounds, ExistentialBounds}
;
60 pub use self::sty
::{BareFnTy, FnSig, PolyFnSig, FnOutput, PolyFnOutput}
;
61 pub use self::sty
::{ClosureTy, InferTy, ParamTy, ProjectionTy, TraitTy}
;
62 pub use self::sty
::{ClosureSubsts, TypeAndMut}
;
63 pub use self::sty
::{TraitRef, TypeVariants, PolyTraitRef}
;
64 pub use self::sty
::{BoundRegion, EarlyBoundRegion, FreeRegion, Region}
;
65 pub use self::sty
::{TyVid, IntVid, FloatVid, RegionVid, SkolemizedRegionVid}
;
66 pub use self::sty
::BoundRegion
::*;
67 pub use self::sty
::FnOutput
::*;
68 pub use self::sty
::InferTy
::*;
69 pub use self::sty
::Region
::*;
70 pub use self::sty
::TypeVariants
::*;
72 pub use self::sty
::BuiltinBound
::Send
as BoundSend
;
73 pub use self::sty
::BuiltinBound
::Sized
as BoundSized
;
74 pub use self::sty
::BuiltinBound
::Copy
as BoundCopy
;
75 pub use self::sty
::BuiltinBound
::Sync
as BoundSync
;
77 pub use self::contents
::TypeContents
;
78 pub use self::context
::{ctxt, tls}
;
79 pub use self::context
::{CtxtArenas, Lift, Tables}
;
81 pub use self::trait_def
::{TraitDef, TraitFlags}
;
101 mod structural_impls
;
105 pub const INITIAL_DISCRIMINANT_VALUE
: Disr
= 0;
109 /// The complete set of all analyses described in this module. This is
110 /// produced by the driver and fed to trans and later passes.
111 pub struct CrateAnalysis
<'a
> {
112 pub export_map
: ExportMap
,
113 pub access_levels
: middle
::privacy
::AccessLevels
,
114 pub reachable
: NodeSet
,
116 pub glob_map
: Option
<GlobMap
>,
119 #[derive(Copy, Clone)]
126 pub fn is_present(&self) -> bool
{
128 TraitDtor(..) => true,
133 pub fn has_drop_flag(&self) -> bool
{
136 &TraitDtor(flag
) => flag
141 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
142 pub enum ImplOrTraitItemContainer
{
143 TraitContainer(DefId
),
144 ImplContainer(DefId
),
147 impl ImplOrTraitItemContainer
{
148 pub fn id(&self) -> DefId
{
150 TraitContainer(id
) => id
,
151 ImplContainer(id
) => id
,
157 pub enum ImplOrTraitItem
<'tcx
> {
158 ConstTraitItem(Rc
<AssociatedConst
<'tcx
>>),
159 MethodTraitItem(Rc
<Method
<'tcx
>>),
160 TypeTraitItem(Rc
<AssociatedType
<'tcx
>>),
163 impl<'tcx
> ImplOrTraitItem
<'tcx
> {
164 fn id(&self) -> ImplOrTraitItemId
{
166 ConstTraitItem(ref associated_const
) => {
167 ConstTraitItemId(associated_const
.def_id
)
169 MethodTraitItem(ref method
) => MethodTraitItemId(method
.def_id
),
170 TypeTraitItem(ref associated_type
) => {
171 TypeTraitItemId(associated_type
.def_id
)
176 pub fn def_id(&self) -> DefId
{
178 ConstTraitItem(ref associated_const
) => associated_const
.def_id
,
179 MethodTraitItem(ref method
) => method
.def_id
,
180 TypeTraitItem(ref associated_type
) => associated_type
.def_id
,
184 pub fn name(&self) -> Name
{
186 ConstTraitItem(ref associated_const
) => associated_const
.name
,
187 MethodTraitItem(ref method
) => method
.name
,
188 TypeTraitItem(ref associated_type
) => associated_type
.name
,
192 pub fn vis(&self) -> hir
::Visibility
{
194 ConstTraitItem(ref associated_const
) => associated_const
.vis
,
195 MethodTraitItem(ref method
) => method
.vis
,
196 TypeTraitItem(ref associated_type
) => associated_type
.vis
,
200 pub fn container(&self) -> ImplOrTraitItemContainer
{
202 ConstTraitItem(ref associated_const
) => associated_const
.container
,
203 MethodTraitItem(ref method
) => method
.container
,
204 TypeTraitItem(ref associated_type
) => associated_type
.container
,
208 pub fn as_opt_method(&self) -> Option
<Rc
<Method
<'tcx
>>> {
210 MethodTraitItem(ref m
) => Some((*m
).clone()),
216 #[derive(Clone, Copy, Debug)]
217 pub enum ImplOrTraitItemId
{
218 ConstTraitItemId(DefId
),
219 MethodTraitItemId(DefId
),
220 TypeTraitItemId(DefId
),
223 impl ImplOrTraitItemId
{
224 pub fn def_id(&self) -> DefId
{
226 ConstTraitItemId(def_id
) => def_id
,
227 MethodTraitItemId(def_id
) => def_id
,
228 TypeTraitItemId(def_id
) => def_id
,
233 #[derive(Clone, Debug)]
234 pub struct Method
<'tcx
> {
236 pub generics
: Generics
<'tcx
>,
237 pub predicates
: GenericPredicates
<'tcx
>,
238 pub fty
: BareFnTy
<'tcx
>,
239 pub explicit_self
: ExplicitSelfCategory
,
240 pub vis
: hir
::Visibility
,
242 pub container
: ImplOrTraitItemContainer
,
245 impl<'tcx
> Method
<'tcx
> {
246 pub fn new(name
: Name
,
247 generics
: ty
::Generics
<'tcx
>,
248 predicates
: GenericPredicates
<'tcx
>,
250 explicit_self
: ExplicitSelfCategory
,
251 vis
: hir
::Visibility
,
253 container
: ImplOrTraitItemContainer
)
258 predicates
: predicates
,
260 explicit_self
: explicit_self
,
263 container
: container
,
267 pub fn container_id(&self) -> DefId
{
268 match self.container
{
269 TraitContainer(id
) => id
,
270 ImplContainer(id
) => id
,
275 impl<'tcx
> PartialEq
for Method
<'tcx
> {
277 fn eq(&self, other
: &Self) -> bool { self.def_id == other.def_id }
280 impl<'tcx
> Eq
for Method
<'tcx
> {}
282 impl<'tcx
> Hash
for Method
<'tcx
> {
284 fn hash
<H
: Hasher
>(&self, s
: &mut H
) {
289 #[derive(Clone, Copy, Debug)]
290 pub struct AssociatedConst
<'tcx
> {
293 pub vis
: hir
::Visibility
,
295 pub container
: ImplOrTraitItemContainer
,
299 #[derive(Clone, Copy, Debug)]
300 pub struct AssociatedType
<'tcx
> {
302 pub ty
: Option
<Ty
<'tcx
>>,
303 pub vis
: hir
::Visibility
,
305 pub container
: ImplOrTraitItemContainer
,
308 #[derive(Clone, PartialEq, RustcDecodable, RustcEncodable)]
309 pub struct ItemVariances
{
310 pub types
: VecPerParamSpace
<Variance
>,
311 pub regions
: VecPerParamSpace
<Variance
>,
314 #[derive(Clone, PartialEq, RustcDecodable, RustcEncodable, Copy)]
316 Covariant
, // T<A> <: T<B> iff A <: B -- e.g., function return type
317 Invariant
, // T<A> <: T<B> iff B == A -- e.g., type of mutable cell
318 Contravariant
, // T<A> <: T<B> iff B <: A -- e.g., function param type
319 Bivariant
, // T<A> <: T<B> -- e.g., unused type parameter
322 #[derive(Clone, Copy, Debug)]
323 pub struct MethodCallee
<'tcx
> {
324 /// Impl method ID, for inherent methods, or trait method ID, otherwise.
327 pub substs
: &'tcx subst
::Substs
<'tcx
>
330 /// With method calls, we store some extra information in
331 /// side tables (i.e method_map). We use
332 /// MethodCall as a key to index into these tables instead of
333 /// just directly using the expression's NodeId. The reason
334 /// for this being that we may apply adjustments (coercions)
335 /// with the resulting expression also needing to use the
336 /// side tables. The problem with this is that we don't
337 /// assign a separate NodeId to this new expression
338 /// and so it would clash with the base expression if both
339 /// needed to add to the side tables. Thus to disambiguate
340 /// we also keep track of whether there's an adjustment in
342 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
343 pub struct MethodCall
{
349 pub fn expr(id
: NodeId
) -> MethodCall
{
356 pub fn autoderef(expr_id
: NodeId
, autoderef
: u32) -> MethodCall
{
359 autoderef
: 1 + autoderef
364 // maps from an expression id that corresponds to a method call to the details
365 // of the method to be invoked
366 pub type MethodMap
<'tcx
> = FnvHashMap
<MethodCall
, MethodCallee
<'tcx
>>;
368 // Contains information needed to resolve types and (in the future) look up
369 // the types of AST nodes.
370 #[derive(Copy, Clone, PartialEq, Eq, Hash)]
371 pub struct CReaderCacheKey
{
376 /// A restriction that certain types must be the same size. The use of
377 /// `transmute` gives rise to these restrictions. These generally
378 /// cannot be checked until trans; therefore, each call to `transmute`
379 /// will push one or more such restriction into the
380 /// `transmute_restrictions` vector during `intrinsicck`. They are
381 /// then checked during `trans` by the fn `check_intrinsics`.
382 #[derive(Copy, Clone)]
383 pub struct TransmuteRestriction
<'tcx
> {
384 /// The span whence the restriction comes.
387 /// The type being transmuted from.
388 pub original_from
: Ty
<'tcx
>,
390 /// The type being transmuted to.
391 pub original_to
: Ty
<'tcx
>,
393 /// The type being transmuted from, with all type parameters
394 /// substituted for an arbitrary representative. Not to be shown
396 pub substituted_from
: Ty
<'tcx
>,
398 /// The type being transmuted to, with all type parameters
399 /// substituted for an arbitrary representative. Not to be shown
401 pub substituted_to
: Ty
<'tcx
>,
403 /// NodeId of the transmute intrinsic.
407 /// Describes the fragment-state associated with a NodeId.
409 /// Currently only unfragmented paths have entries in the table,
410 /// but longer-term this enum is expected to expand to also
411 /// include data for fragmented paths.
412 #[derive(Copy, Clone, Debug)]
413 pub enum FragmentInfo
{
414 Moved { var: NodeId, move_expr: NodeId }
,
415 Assigned { var: NodeId, assign_expr: NodeId, assignee_id: NodeId }
,
418 // Flags that we track on types. These flags are propagated upwards
419 // through the type during type construction, so that we can quickly
420 // check whether the type has various kinds of types in it without
421 // recursing over the type itself.
423 flags TypeFlags
: u32 {
424 const HAS_PARAMS
= 1 << 0,
425 const HAS_SELF
= 1 << 1,
426 const HAS_TY_INFER
= 1 << 2,
427 const HAS_RE_INFER
= 1 << 3,
428 const HAS_RE_EARLY_BOUND
= 1 << 4,
429 const HAS_FREE_REGIONS
= 1 << 5,
430 const HAS_TY_ERR
= 1 << 6,
431 const HAS_PROJECTION
= 1 << 7,
432 const HAS_TY_CLOSURE
= 1 << 8,
434 // true if there are "names" of types and regions and so forth
435 // that are local to a particular fn
436 const HAS_LOCAL_NAMES
= 1 << 9,
438 const NEEDS_SUBST
= TypeFlags
::HAS_PARAMS
.bits
|
439 TypeFlags
::HAS_SELF
.bits
|
440 TypeFlags
::HAS_RE_EARLY_BOUND
.bits
,
442 // Flags representing the nominal content of a type,
443 // computed by FlagsComputation. If you add a new nominal
444 // flag, it should be added here too.
445 const NOMINAL_FLAGS
= TypeFlags
::HAS_PARAMS
.bits
|
446 TypeFlags
::HAS_SELF
.bits
|
447 TypeFlags
::HAS_TY_INFER
.bits
|
448 TypeFlags
::HAS_RE_INFER
.bits
|
449 TypeFlags
::HAS_RE_EARLY_BOUND
.bits
|
450 TypeFlags
::HAS_FREE_REGIONS
.bits
|
451 TypeFlags
::HAS_TY_ERR
.bits
|
452 TypeFlags
::HAS_PROJECTION
.bits
|
453 TypeFlags
::HAS_TY_CLOSURE
.bits
|
454 TypeFlags
::HAS_LOCAL_NAMES
.bits
,
456 // Caches for type_is_sized, type_moves_by_default
457 const SIZEDNESS_CACHED
= 1 << 16,
458 const IS_SIZED
= 1 << 17,
459 const MOVENESS_CACHED
= 1 << 18,
460 const MOVES_BY_DEFAULT
= 1 << 19,
464 pub struct TyS
<'tcx
> {
465 pub sty
: TypeVariants
<'tcx
>,
466 pub flags
: Cell
<TypeFlags
>,
468 // the maximal depth of any bound regions appearing in this type.
472 impl<'tcx
> PartialEq
for TyS
<'tcx
> {
474 fn eq(&self, other
: &TyS
<'tcx
>) -> bool
{
475 // (self as *const _) == (other as *const _)
476 (self as *const TyS
<'tcx
>) == (other
as *const TyS
<'tcx
>)
479 impl<'tcx
> Eq
for TyS
<'tcx
> {}
481 impl<'tcx
> Hash
for TyS
<'tcx
> {
482 fn hash
<H
: Hasher
>(&self, s
: &mut H
) {
483 (self as *const TyS
).hash(s
)
487 pub type Ty
<'tcx
> = &'tcx TyS
<'tcx
>;
489 impl<'tcx
> Encodable
for Ty
<'tcx
> {
490 fn encode
<S
: Encoder
>(&self, s
: &mut S
) -> Result
<(), S
::Error
> {
491 cstore
::tls
::with_encoding_context(s
, |ecx
, rbml_w
| {
492 ecx
.encode_ty(rbml_w
, *self);
498 impl<'tcx
> Decodable
for Ty
<'tcx
> {
499 fn decode
<D
: Decoder
>(d
: &mut D
) -> Result
<Ty
<'tcx
>, D
::Error
> {
500 cstore
::tls
::with_decoding_context(d
, |dcx
, rbml_r
| {
501 Ok(dcx
.decode_ty(rbml_r
))
507 /// Upvars do not get their own node-id. Instead, we use the pair of
508 /// the original var id (that is, the root variable that is referenced
509 /// by the upvar) and the id of the closure expression.
510 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
513 pub closure_expr_id
: NodeId
,
516 #[derive(Clone, PartialEq, Eq, Hash, Debug, RustcEncodable, RustcDecodable, Copy)]
517 pub enum BorrowKind
{
518 /// Data must be immutable and is aliasable.
521 /// Data must be immutable but not aliasable. This kind of borrow
522 /// cannot currently be expressed by the user and is used only in
523 /// implicit closure bindings. It is needed when you the closure
524 /// is borrowing or mutating a mutable referent, e.g.:
526 /// let x: &mut isize = ...;
527 /// let y = || *x += 5;
529 /// If we were to try to translate this closure into a more explicit
530 /// form, we'd encounter an error with the code as written:
532 /// struct Env { x: & &mut isize }
533 /// let x: &mut isize = ...;
534 /// let y = (&mut Env { &x }, fn_ptr); // Closure is pair of env and fn
535 /// fn fn_ptr(env: &mut Env) { **env.x += 5; }
537 /// This is then illegal because you cannot mutate a `&mut` found
538 /// in an aliasable location. To solve, you'd have to translate with
539 /// an `&mut` borrow:
541 /// struct Env { x: & &mut isize }
542 /// let x: &mut isize = ...;
543 /// let y = (&mut Env { &mut x }, fn_ptr); // changed from &x to &mut x
544 /// fn fn_ptr(env: &mut Env) { **env.x += 5; }
546 /// Now the assignment to `**env.x` is legal, but creating a
547 /// mutable pointer to `x` is not because `x` is not mutable. We
548 /// could fix this by declaring `x` as `let mut x`. This is ok in
549 /// user code, if awkward, but extra weird for closures, since the
550 /// borrow is hidden.
552 /// So we introduce a "unique imm" borrow -- the referent is
553 /// immutable, but not aliasable. This solves the problem. For
554 /// simplicity, we don't give users the way to express this
555 /// borrow, it's just used when translating closures.
558 /// Data is mutable and not aliasable.
562 /// Information describing the capture of an upvar. This is computed
563 /// during `typeck`, specifically by `regionck`.
564 #[derive(PartialEq, Clone, Debug, Copy)]
565 pub enum UpvarCapture
{
566 /// Upvar is captured by value. This is always true when the
567 /// closure is labeled `move`, but can also be true in other cases
568 /// depending on inference.
571 /// Upvar is captured by reference.
575 #[derive(PartialEq, Clone, Copy)]
576 pub struct UpvarBorrow
{
577 /// The kind of borrow: by-ref upvars have access to shared
578 /// immutable borrows, which are not part of the normal language
580 pub kind
: BorrowKind
,
582 /// Region of the resulting reference.
583 pub region
: ty
::Region
,
586 pub type UpvarCaptureMap
= FnvHashMap
<UpvarId
, UpvarCapture
>;
588 #[derive(Copy, Clone)]
589 pub struct ClosureUpvar
<'tcx
> {
595 #[derive(Clone, Copy, PartialEq)]
596 pub enum IntVarValue
{
598 UintType(ast
::UintTy
),
601 /// Default region to use for the bound of objects that are
602 /// supplied as the value for this type parameter. This is derived
603 /// from `T:'a` annotations appearing in the type definition. If
604 /// this is `None`, then the default is inherited from the
605 /// surrounding context. See RFC #599 for details.
606 #[derive(Copy, Clone)]
607 pub enum ObjectLifetimeDefault
{
608 /// Require an explicit annotation. Occurs when multiple
609 /// `T:'a` constraints are found.
612 /// Use the base default, typically 'static, but in a fn body it is a fresh variable
615 /// Use the given region as the default.
620 pub struct TypeParameterDef
<'tcx
> {
623 pub space
: subst
::ParamSpace
,
625 pub default_def_id
: DefId
, // for use in error reporing about defaults
626 pub default: Option
<Ty
<'tcx
>>,
627 pub object_lifetime_default
: ObjectLifetimeDefault
,
631 pub struct RegionParameterDef
{
634 pub space
: subst
::ParamSpace
,
636 pub bounds
: Vec
<ty
::Region
>,
639 impl RegionParameterDef
{
640 pub fn to_early_bound_region(&self) -> ty
::Region
{
641 ty
::ReEarlyBound(ty
::EarlyBoundRegion
{
647 pub fn to_bound_region(&self) -> ty
::BoundRegion
{
648 ty
::BoundRegion
::BrNamed(self.def_id
, self.name
)
652 /// Information about the formal type/lifetime parameters associated
653 /// with an item or method. Analogous to hir::Generics.
654 #[derive(Clone, Debug)]
655 pub struct Generics
<'tcx
> {
656 pub types
: VecPerParamSpace
<TypeParameterDef
<'tcx
>>,
657 pub regions
: VecPerParamSpace
<RegionParameterDef
>,
660 impl<'tcx
> Generics
<'tcx
> {
661 pub fn empty() -> Generics
<'tcx
> {
663 types
: VecPerParamSpace
::empty(),
664 regions
: VecPerParamSpace
::empty(),
668 pub fn is_empty(&self) -> bool
{
669 self.types
.is_empty() && self.regions
.is_empty()
672 pub fn has_type_params(&self, space
: subst
::ParamSpace
) -> bool
{
673 !self.types
.is_empty_in(space
)
676 pub fn has_region_params(&self, space
: subst
::ParamSpace
) -> bool
{
677 !self.regions
.is_empty_in(space
)
681 /// Bounds on generics.
683 pub struct GenericPredicates
<'tcx
> {
684 pub predicates
: VecPerParamSpace
<Predicate
<'tcx
>>,
687 impl<'tcx
> GenericPredicates
<'tcx
> {
688 pub fn empty() -> GenericPredicates
<'tcx
> {
690 predicates
: VecPerParamSpace
::empty(),
694 pub fn instantiate(&self, tcx
: &ctxt
<'tcx
>, substs
: &Substs
<'tcx
>)
695 -> InstantiatedPredicates
<'tcx
> {
696 InstantiatedPredicates
{
697 predicates
: self.predicates
.subst(tcx
, substs
),
701 pub fn instantiate_supertrait(&self,
703 poly_trait_ref
: &ty
::PolyTraitRef
<'tcx
>)
704 -> InstantiatedPredicates
<'tcx
>
706 InstantiatedPredicates
{
707 predicates
: self.predicates
.map(|pred
| pred
.subst_supertrait(tcx
, poly_trait_ref
))
712 #[derive(Clone, PartialEq, Eq, Hash)]
713 pub enum Predicate
<'tcx
> {
714 /// Corresponds to `where Foo : Bar<A,B,C>`. `Foo` here would be
715 /// the `Self` type of the trait reference and `A`, `B`, and `C`
716 /// would be the parameters in the `TypeSpace`.
717 Trait(PolyTraitPredicate
<'tcx
>),
719 /// where `T1 == T2`.
720 Equate(PolyEquatePredicate
<'tcx
>),
723 RegionOutlives(PolyRegionOutlivesPredicate
),
726 TypeOutlives(PolyTypeOutlivesPredicate
<'tcx
>),
728 /// where <T as TraitRef>::Name == X, approximately.
729 /// See `ProjectionPredicate` struct for details.
730 Projection(PolyProjectionPredicate
<'tcx
>),
733 WellFormed(Ty
<'tcx
>),
735 /// trait must be object-safe
739 impl<'tcx
> Predicate
<'tcx
> {
740 /// Performs a substitution suitable for going from a
741 /// poly-trait-ref to supertraits that must hold if that
742 /// poly-trait-ref holds. This is slightly different from a normal
743 /// substitution in terms of what happens with bound regions. See
744 /// lengthy comment below for details.
745 pub fn subst_supertrait(&self,
747 trait_ref
: &ty
::PolyTraitRef
<'tcx
>)
748 -> ty
::Predicate
<'tcx
>
750 // The interaction between HRTB and supertraits is not entirely
751 // obvious. Let me walk you (and myself) through an example.
753 // Let's start with an easy case. Consider two traits:
755 // trait Foo<'a> : Bar<'a,'a> { }
756 // trait Bar<'b,'c> { }
758 // Now, if we have a trait reference `for<'x> T : Foo<'x>`, then
759 // we can deduce that `for<'x> T : Bar<'x,'x>`. Basically, if we
760 // knew that `Foo<'x>` (for any 'x) then we also know that
761 // `Bar<'x,'x>` (for any 'x). This more-or-less falls out from
762 // normal substitution.
764 // In terms of why this is sound, the idea is that whenever there
765 // is an impl of `T:Foo<'a>`, it must show that `T:Bar<'a,'a>`
766 // holds. So if there is an impl of `T:Foo<'a>` that applies to
767 // all `'a`, then we must know that `T:Bar<'a,'a>` holds for all
770 // Another example to be careful of is this:
772 // trait Foo1<'a> : for<'b> Bar1<'a,'b> { }
773 // trait Bar1<'b,'c> { }
775 // Here, if we have `for<'x> T : Foo1<'x>`, then what do we know?
776 // The answer is that we know `for<'x,'b> T : Bar1<'x,'b>`. The
777 // reason is similar to the previous example: any impl of
778 // `T:Foo1<'x>` must show that `for<'b> T : Bar1<'x, 'b>`. So
779 // basically we would want to collapse the bound lifetimes from
780 // the input (`trait_ref`) and the supertraits.
782 // To achieve this in practice is fairly straightforward. Let's
783 // consider the more complicated scenario:
785 // - We start out with `for<'x> T : Foo1<'x>`. In this case, `'x`
786 // has a De Bruijn index of 1. We want to produce `for<'x,'b> T : Bar1<'x,'b>`,
787 // where both `'x` and `'b` would have a DB index of 1.
788 // The substitution from the input trait-ref is therefore going to be
789 // `'a => 'x` (where `'x` has a DB index of 1).
790 // - The super-trait-ref is `for<'b> Bar1<'a,'b>`, where `'a` is an
791 // early-bound parameter and `'b' is a late-bound parameter with a
793 // - If we replace `'a` with `'x` from the input, it too will have
794 // a DB index of 1, and thus we'll have `for<'x,'b> Bar1<'x,'b>`
795 // just as we wanted.
797 // There is only one catch. If we just apply the substitution `'a
798 // => 'x` to `for<'b> Bar1<'a,'b>`, the substitution code will
799 // adjust the DB index because we substituting into a binder (it
800 // tries to be so smart...) resulting in `for<'x> for<'b>
801 // Bar1<'x,'b>` (we have no syntax for this, so use your
802 // imagination). Basically the 'x will have DB index of 2 and 'b
803 // will have DB index of 1. Not quite what we want. So we apply
804 // the substitution to the *contents* of the trait reference,
805 // rather than the trait reference itself (put another way, the
806 // substitution code expects equal binding levels in the values
807 // from the substitution and the value being substituted into, and
808 // this trick achieves that).
810 let substs
= &trait_ref
.0.substs
;
812 Predicate
::Trait(ty
::Binder(ref data
)) =>
813 Predicate
::Trait(ty
::Binder(data
.subst(tcx
, substs
))),
814 Predicate
::Equate(ty
::Binder(ref data
)) =>
815 Predicate
::Equate(ty
::Binder(data
.subst(tcx
, substs
))),
816 Predicate
::RegionOutlives(ty
::Binder(ref data
)) =>
817 Predicate
::RegionOutlives(ty
::Binder(data
.subst(tcx
, substs
))),
818 Predicate
::TypeOutlives(ty
::Binder(ref data
)) =>
819 Predicate
::TypeOutlives(ty
::Binder(data
.subst(tcx
, substs
))),
820 Predicate
::Projection(ty
::Binder(ref data
)) =>
821 Predicate
::Projection(ty
::Binder(data
.subst(tcx
, substs
))),
822 Predicate
::WellFormed(data
) =>
823 Predicate
::WellFormed(data
.subst(tcx
, substs
)),
824 Predicate
::ObjectSafe(trait_def_id
) =>
825 Predicate
::ObjectSafe(trait_def_id
),
830 #[derive(Clone, PartialEq, Eq, Hash)]
831 pub struct TraitPredicate
<'tcx
> {
832 pub trait_ref
: TraitRef
<'tcx
>
834 pub type PolyTraitPredicate
<'tcx
> = ty
::Binder
<TraitPredicate
<'tcx
>>;
836 impl<'tcx
> TraitPredicate
<'tcx
> {
837 pub fn def_id(&self) -> DefId
{
838 self.trait_ref
.def_id
841 /// Creates the dep-node for selecting/evaluating this trait reference.
842 fn dep_node(&self) -> DepNode
{
843 DepNode
::TraitSelect(self.def_id())
846 pub fn input_types(&self) -> &[Ty
<'tcx
>] {
847 self.trait_ref
.substs
.types
.as_slice()
850 pub fn self_ty(&self) -> Ty
<'tcx
> {
851 self.trait_ref
.self_ty()
855 impl<'tcx
> PolyTraitPredicate
<'tcx
> {
856 pub fn def_id(&self) -> DefId
{
857 // ok to skip binder since trait def-id does not care about regions
861 pub fn dep_node(&self) -> DepNode
{
862 // ok to skip binder since depnode does not care about regions
867 #[derive(Clone, PartialEq, Eq, Hash, Debug)]
868 pub struct EquatePredicate
<'tcx
>(pub Ty
<'tcx
>, pub Ty
<'tcx
>); // `0 == 1`
869 pub type PolyEquatePredicate
<'tcx
> = ty
::Binder
<EquatePredicate
<'tcx
>>;
871 #[derive(Clone, PartialEq, Eq, Hash, Debug)]
872 pub struct OutlivesPredicate
<A
,B
>(pub A
, pub B
); // `A : B`
873 pub type PolyOutlivesPredicate
<A
,B
> = ty
::Binder
<OutlivesPredicate
<A
,B
>>;
874 pub type PolyRegionOutlivesPredicate
= PolyOutlivesPredicate
<ty
::Region
, ty
::Region
>;
875 pub type PolyTypeOutlivesPredicate
<'tcx
> = PolyOutlivesPredicate
<Ty
<'tcx
>, ty
::Region
>;
877 /// This kind of predicate has no *direct* correspondent in the
878 /// syntax, but it roughly corresponds to the syntactic forms:
880 /// 1. `T : TraitRef<..., Item=Type>`
881 /// 2. `<T as TraitRef<...>>::Item == Type` (NYI)
883 /// In particular, form #1 is "desugared" to the combination of a
884 /// normal trait predicate (`T : TraitRef<...>`) and one of these
885 /// predicates. Form #2 is a broader form in that it also permits
886 /// equality between arbitrary types. Processing an instance of Form
887 /// #2 eventually yields one of these `ProjectionPredicate`
888 /// instances to normalize the LHS.
889 #[derive(Clone, PartialEq, Eq, Hash)]
890 pub struct ProjectionPredicate
<'tcx
> {
891 pub projection_ty
: ProjectionTy
<'tcx
>,
895 pub type PolyProjectionPredicate
<'tcx
> = Binder
<ProjectionPredicate
<'tcx
>>;
897 impl<'tcx
> PolyProjectionPredicate
<'tcx
> {
898 pub fn item_name(&self) -> Name
{
899 self.0.projection_ty
.item_name
// safe to skip the binder to access a name
902 pub fn sort_key(&self) -> (DefId
, Name
) {
903 self.0.projection_ty
.sort_key()
907 pub trait ToPolyTraitRef
<'tcx
> {
908 fn to_poly_trait_ref(&self) -> PolyTraitRef
<'tcx
>;
911 impl<'tcx
> ToPolyTraitRef
<'tcx
> for TraitRef
<'tcx
> {
912 fn to_poly_trait_ref(&self) -> PolyTraitRef
<'tcx
> {
913 assert
!(!self.has_escaping_regions());
914 ty
::Binder(self.clone())
918 impl<'tcx
> ToPolyTraitRef
<'tcx
> for PolyTraitPredicate
<'tcx
> {
919 fn to_poly_trait_ref(&self) -> PolyTraitRef
<'tcx
> {
920 self.map_bound_ref(|trait_pred
| trait_pred
.trait_ref
)
924 impl<'tcx
> ToPolyTraitRef
<'tcx
> for PolyProjectionPredicate
<'tcx
> {
925 fn to_poly_trait_ref(&self) -> PolyTraitRef
<'tcx
> {
926 // Note: unlike with TraitRef::to_poly_trait_ref(),
927 // self.0.trait_ref is permitted to have escaping regions.
928 // This is because here `self` has a `Binder` and so does our
929 // return value, so we are preserving the number of binding
931 ty
::Binder(self.0.projection_ty
.trait_ref
)
935 pub trait ToPredicate
<'tcx
> {
936 fn to_predicate(&self) -> Predicate
<'tcx
>;
939 impl<'tcx
> ToPredicate
<'tcx
> for TraitRef
<'tcx
> {
940 fn to_predicate(&self) -> Predicate
<'tcx
> {
941 // we're about to add a binder, so let's check that we don't
942 // accidentally capture anything, or else that might be some
943 // weird debruijn accounting.
944 assert
!(!self.has_escaping_regions());
946 ty
::Predicate
::Trait(ty
::Binder(ty
::TraitPredicate
{
947 trait_ref
: self.clone()
952 impl<'tcx
> ToPredicate
<'tcx
> for PolyTraitRef
<'tcx
> {
953 fn to_predicate(&self) -> Predicate
<'tcx
> {
954 ty
::Predicate
::Trait(self.to_poly_trait_predicate())
958 impl<'tcx
> ToPredicate
<'tcx
> for PolyEquatePredicate
<'tcx
> {
959 fn to_predicate(&self) -> Predicate
<'tcx
> {
960 Predicate
::Equate(self.clone())
964 impl<'tcx
> ToPredicate
<'tcx
> for PolyRegionOutlivesPredicate
{
965 fn to_predicate(&self) -> Predicate
<'tcx
> {
966 Predicate
::RegionOutlives(self.clone())
970 impl<'tcx
> ToPredicate
<'tcx
> for PolyTypeOutlivesPredicate
<'tcx
> {
971 fn to_predicate(&self) -> Predicate
<'tcx
> {
972 Predicate
::TypeOutlives(self.clone())
976 impl<'tcx
> ToPredicate
<'tcx
> for PolyProjectionPredicate
<'tcx
> {
977 fn to_predicate(&self) -> Predicate
<'tcx
> {
978 Predicate
::Projection(self.clone())
982 impl<'tcx
> Predicate
<'tcx
> {
983 /// Iterates over the types in this predicate. Note that in all
984 /// cases this is skipping over a binder, so late-bound regions
985 /// with depth 0 are bound by the predicate.
986 pub fn walk_tys(&self) -> IntoIter
<Ty
<'tcx
>> {
987 let vec
: Vec
<_
> = match *self {
988 ty
::Predicate
::Trait(ref data
) => {
989 data
.0.trait_ref
.substs
.types
.as_slice().to_vec()
991 ty
::Predicate
::Equate(ty
::Binder(ref data
)) => {
994 ty
::Predicate
::TypeOutlives(ty
::Binder(ref data
)) => {
997 ty
::Predicate
::RegionOutlives(..) => {
1000 ty
::Predicate
::Projection(ref data
) => {
1001 let trait_inputs
= data
.0.projection_ty
.trait_ref
.substs
.types
.as_slice();
1004 .chain(Some(data
.0.ty
))
1007 ty
::Predicate
::WellFormed(data
) => {
1010 ty
::Predicate
::ObjectSafe(_trait_def_id
) => {
1015 // The only reason to collect into a vector here is that I was
1016 // too lazy to make the full (somewhat complicated) iterator
1017 // type that would be needed here. But I wanted this fn to
1018 // return an iterator conceptually, rather than a `Vec`, so as
1019 // to be closer to `Ty::walk`.
1023 pub fn to_opt_poly_trait_ref(&self) -> Option
<PolyTraitRef
<'tcx
>> {
1025 Predicate
::Trait(ref t
) => {
1026 Some(t
.to_poly_trait_ref())
1028 Predicate
::Projection(..) |
1029 Predicate
::Equate(..) |
1030 Predicate
::RegionOutlives(..) |
1031 Predicate
::WellFormed(..) |
1032 Predicate
::ObjectSafe(..) |
1033 Predicate
::TypeOutlives(..) => {
1040 /// Represents the bounds declared on a particular set of type
1041 /// parameters. Should eventually be generalized into a flag list of
1042 /// where clauses. You can obtain a `InstantiatedPredicates` list from a
1043 /// `GenericPredicates` by using the `instantiate` method. Note that this method
1044 /// reflects an important semantic invariant of `InstantiatedPredicates`: while
1045 /// the `GenericPredicates` are expressed in terms of the bound type
1046 /// parameters of the impl/trait/whatever, an `InstantiatedPredicates` instance
1047 /// represented a set of bounds for some particular instantiation,
1048 /// meaning that the generic parameters have been substituted with
1053 /// struct Foo<T,U:Bar<T>> { ... }
1055 /// Here, the `GenericPredicates` for `Foo` would contain a list of bounds like
1056 /// `[[], [U:Bar<T>]]`. Now if there were some particular reference
1057 /// like `Foo<isize,usize>`, then the `InstantiatedPredicates` would be `[[],
1058 /// [usize:Bar<isize>]]`.
1060 pub struct InstantiatedPredicates
<'tcx
> {
1061 pub predicates
: VecPerParamSpace
<Predicate
<'tcx
>>,
1064 impl<'tcx
> InstantiatedPredicates
<'tcx
> {
1065 pub fn empty() -> InstantiatedPredicates
<'tcx
> {
1066 InstantiatedPredicates { predicates: VecPerParamSpace::empty() }
1069 pub fn is_empty(&self) -> bool
{
1070 self.predicates
.is_empty()
1074 impl<'tcx
> TraitRef
<'tcx
> {
1075 pub fn new(def_id
: DefId
, substs
: &'tcx Substs
<'tcx
>) -> TraitRef
<'tcx
> {
1076 TraitRef { def_id: def_id, substs: substs }
1079 pub fn self_ty(&self) -> Ty
<'tcx
> {
1080 self.substs
.self_ty().unwrap()
1083 pub fn input_types(&self) -> &[Ty
<'tcx
>] {
1084 // Select only the "input types" from a trait-reference. For
1085 // now this is all the types that appear in the
1086 // trait-reference, but it should eventually exclude
1087 // associated types.
1088 self.substs
.types
.as_slice()
1092 /// When type checking, we use the `ParameterEnvironment` to track
1093 /// details about the type/lifetime parameters that are in scope.
1094 /// It primarily stores the bounds information.
1096 /// Note: This information might seem to be redundant with the data in
1097 /// `tcx.ty_param_defs`, but it is not. That table contains the
1098 /// parameter definitions from an "outside" perspective, but this
1099 /// struct will contain the bounds for a parameter as seen from inside
1100 /// the function body. Currently the only real distinction is that
1101 /// bound lifetime parameters are replaced with free ones, but in the
1102 /// future I hope to refine the representation of types so as to make
1103 /// more distinctions clearer.
1105 pub struct ParameterEnvironment
<'a
, 'tcx
:'a
> {
1106 pub tcx
: &'a ctxt
<'tcx
>,
1108 /// See `construct_free_substs` for details.
1109 pub free_substs
: Substs
<'tcx
>,
1111 /// Each type parameter has an implicit region bound that
1112 /// indicates it must outlive at least the function body (the user
1113 /// may specify stronger requirements). This field indicates the
1114 /// region of the callee.
1115 pub implicit_region_bound
: ty
::Region
,
1117 /// Obligations that the caller must satisfy. This is basically
1118 /// the set of bounds on the in-scope type parameters, translated
1119 /// into Obligations, and elaborated and normalized.
1120 pub caller_bounds
: Vec
<ty
::Predicate
<'tcx
>>,
1122 /// Caches the results of trait selection. This cache is used
1123 /// for things that have to do with the parameters in scope.
1124 pub selection_cache
: traits
::SelectionCache
<'tcx
>,
1126 /// Caches the results of trait evaluation.
1127 pub evaluation_cache
: traits
::EvaluationCache
<'tcx
>,
1129 /// Scope that is attached to free regions for this scope. This
1130 /// is usually the id of the fn body, but for more abstract scopes
1131 /// like structs we often use the node-id of the struct.
1133 /// FIXME(#3696). It would be nice to refactor so that free
1134 /// regions don't have this implicit scope and instead introduce
1135 /// relationships in the environment.
1136 pub free_id_outlive
: CodeExtent
,
1139 impl<'a
, 'tcx
> ParameterEnvironment
<'a
, 'tcx
> {
1140 pub fn with_caller_bounds(&self,
1141 caller_bounds
: Vec
<ty
::Predicate
<'tcx
>>)
1142 -> ParameterEnvironment
<'a
,'tcx
>
1144 ParameterEnvironment
{
1146 free_substs
: self.free_substs
.clone(),
1147 implicit_region_bound
: self.implicit_region_bound
,
1148 caller_bounds
: caller_bounds
,
1149 selection_cache
: traits
::SelectionCache
::new(),
1150 evaluation_cache
: traits
::EvaluationCache
::new(),
1151 free_id_outlive
: self.free_id_outlive
,
1155 pub fn for_item(cx
: &'a ctxt
<'tcx
>, id
: NodeId
) -> ParameterEnvironment
<'a
, 'tcx
> {
1156 match cx
.map
.find(id
) {
1157 Some(ast_map
::NodeImplItem(ref impl_item
)) => {
1158 match impl_item
.node
{
1159 hir
::ImplItemKind
::Type(_
) => {
1160 // associated types don't have their own entry (for some reason),
1161 // so for now just grab environment for the impl
1162 let impl_id
= cx
.map
.get_parent(id
);
1163 let impl_def_id
= cx
.map
.local_def_id(impl_id
);
1164 let scheme
= cx
.lookup_item_type(impl_def_id
);
1165 let predicates
= cx
.lookup_predicates(impl_def_id
);
1166 cx
.construct_parameter_environment(impl_item
.span
,
1169 cx
.region_maps
.item_extent(id
))
1171 hir
::ImplItemKind
::Const(_
, _
) => {
1172 let def_id
= cx
.map
.local_def_id(id
);
1173 let scheme
= cx
.lookup_item_type(def_id
);
1174 let predicates
= cx
.lookup_predicates(def_id
);
1175 cx
.construct_parameter_environment(impl_item
.span
,
1178 cx
.region_maps
.item_extent(id
))
1180 hir
::ImplItemKind
::Method(_
, ref body
) => {
1181 let method_def_id
= cx
.map
.local_def_id(id
);
1182 match cx
.impl_or_trait_item(method_def_id
) {
1183 MethodTraitItem(ref method_ty
) => {
1184 let method_generics
= &method_ty
.generics
;
1185 let method_bounds
= &method_ty
.predicates
;
1186 cx
.construct_parameter_environment(
1190 cx
.region_maps
.call_site_extent(id
, body
.id
))
1194 .bug("ParameterEnvironment::for_item(): \
1195 got non-method item from impl method?!")
1201 Some(ast_map
::NodeTraitItem(trait_item
)) => {
1202 match trait_item
.node
{
1203 hir
::TypeTraitItem(..) => {
1204 // associated types don't have their own entry (for some reason),
1205 // so for now just grab environment for the trait
1206 let trait_id
= cx
.map
.get_parent(id
);
1207 let trait_def_id
= cx
.map
.local_def_id(trait_id
);
1208 let trait_def
= cx
.lookup_trait_def(trait_def_id
);
1209 let predicates
= cx
.lookup_predicates(trait_def_id
);
1210 cx
.construct_parameter_environment(trait_item
.span
,
1211 &trait_def
.generics
,
1213 cx
.region_maps
.item_extent(id
))
1215 hir
::ConstTraitItem(..) => {
1216 let def_id
= cx
.map
.local_def_id(id
);
1217 let scheme
= cx
.lookup_item_type(def_id
);
1218 let predicates
= cx
.lookup_predicates(def_id
);
1219 cx
.construct_parameter_environment(trait_item
.span
,
1222 cx
.region_maps
.item_extent(id
))
1224 hir
::MethodTraitItem(_
, ref body
) => {
1225 // Use call-site for extent (unless this is a
1226 // trait method with no default; then fallback
1227 // to the method id).
1228 let method_def_id
= cx
.map
.local_def_id(id
);
1229 match cx
.impl_or_trait_item(method_def_id
) {
1230 MethodTraitItem(ref method_ty
) => {
1231 let method_generics
= &method_ty
.generics
;
1232 let method_bounds
= &method_ty
.predicates
;
1233 let extent
= if let Some(ref body
) = *body
{
1234 // default impl: use call_site extent as free_id_outlive bound.
1235 cx
.region_maps
.call_site_extent(id
, body
.id
)
1237 // no default impl: use item extent as free_id_outlive bound.
1238 cx
.region_maps
.item_extent(id
)
1240 cx
.construct_parameter_environment(
1248 .bug("ParameterEnvironment::for_item(): \
1249 got non-method item from provided \
1256 Some(ast_map
::NodeItem(item
)) => {
1258 hir
::ItemFn(_
, _
, _
, _
, _
, ref body
) => {
1259 // We assume this is a function.
1260 let fn_def_id
= cx
.map
.local_def_id(id
);
1261 let fn_scheme
= cx
.lookup_item_type(fn_def_id
);
1262 let fn_predicates
= cx
.lookup_predicates(fn_def_id
);
1264 cx
.construct_parameter_environment(item
.span
,
1265 &fn_scheme
.generics
,
1267 cx
.region_maps
.call_site_extent(id
,
1271 hir
::ItemStruct(..) |
1273 hir
::ItemConst(..) |
1274 hir
::ItemStatic(..) => {
1275 let def_id
= cx
.map
.local_def_id(id
);
1276 let scheme
= cx
.lookup_item_type(def_id
);
1277 let predicates
= cx
.lookup_predicates(def_id
);
1278 cx
.construct_parameter_environment(item
.span
,
1281 cx
.region_maps
.item_extent(id
))
1283 hir
::ItemTrait(..) => {
1284 let def_id
= cx
.map
.local_def_id(id
);
1285 let trait_def
= cx
.lookup_trait_def(def_id
);
1286 let predicates
= cx
.lookup_predicates(def_id
);
1287 cx
.construct_parameter_environment(item
.span
,
1288 &trait_def
.generics
,
1290 cx
.region_maps
.item_extent(id
))
1293 cx
.sess
.span_bug(item
.span
,
1294 "ParameterEnvironment::from_item():
1295 can't create a parameter \
1296 environment for this kind of item")
1300 Some(ast_map
::NodeExpr(..)) => {
1301 // This is a convenience to allow closures to work.
1302 ParameterEnvironment
::for_item(cx
, cx
.map
.get_parent(id
))
1305 cx
.sess
.bug(&format
!("ParameterEnvironment::from_item(): \
1306 `{}` is not an item",
1307 cx
.map
.node_to_string(id
)))
1313 /// A "type scheme", in ML terminology, is a type combined with some
1314 /// set of generic types that the type is, well, generic over. In Rust
1315 /// terms, it is the "type" of a fn item or struct -- this type will
1316 /// include various generic parameters that must be substituted when
1317 /// the item/struct is referenced. That is called converting the type
1318 /// scheme to a monotype.
1320 /// - `generics`: the set of type parameters and their bounds
1321 /// - `ty`: the base types, which may reference the parameters defined
1324 /// Note that TypeSchemes are also sometimes called "polytypes" (and
1325 /// in fact this struct used to carry that name, so you may find some
1326 /// stray references in a comment or something). We try to reserve the
1327 /// "poly" prefix to refer to higher-ranked things, as in
1330 /// Note that each item also comes with predicates, see
1331 /// `lookup_predicates`.
1332 #[derive(Clone, Debug)]
1333 pub struct TypeScheme
<'tcx
> {
1334 pub generics
: Generics
<'tcx
>,
1339 flags AdtFlags
: u32 {
1340 const NO_ADT_FLAGS
= 0,
1341 const IS_ENUM
= 1 << 0,
1342 const IS_DTORCK
= 1 << 1, // is this a dtorck type?
1343 const IS_DTORCK_VALID
= 1 << 2,
1344 const IS_PHANTOM_DATA
= 1 << 3,
1345 const IS_SIMD
= 1 << 4,
1346 const IS_FUNDAMENTAL
= 1 << 5,
1347 const IS_NO_DROP_FLAG
= 1 << 6,
1351 pub type AdtDef
<'tcx
> = &'tcx AdtDefData
<'tcx
, '
static>;
1352 pub type VariantDef
<'tcx
> = &'tcx VariantDefData
<'tcx
, '
static>;
1353 pub type FieldDef
<'tcx
> = &'tcx FieldDefData
<'tcx
, '
static>;
1355 // See comment on AdtDefData for explanation
1356 pub type AdtDefMaster
<'tcx
> = &'tcx AdtDefData
<'tcx
, 'tcx
>;
1357 pub type VariantDefMaster
<'tcx
> = &'tcx VariantDefData
<'tcx
, 'tcx
>;
1358 pub type FieldDefMaster
<'tcx
> = &'tcx FieldDefData
<'tcx
, 'tcx
>;
1360 pub struct VariantDefData
<'tcx
, 'container
: 'tcx
> {
1361 /// The variant's DefId. If this is a tuple-like struct,
1362 /// this is the DefId of the struct's ctor.
1364 pub name
: Name
, // struct's name if this is a struct
1366 pub fields
: Vec
<FieldDefData
<'tcx
, 'container
>>,
1367 pub kind
: VariantKind
,
1370 pub struct FieldDefData
<'tcx
, 'container
: 'tcx
> {
1371 /// The field's DefId. NOTE: the fields of tuple-like enum variants
1372 /// are not real items, and don't have entries in tcache etc.
1374 /// special_idents::unnamed_field.name
1375 /// if this is a tuple-like field
1377 pub vis
: hir
::Visibility
,
1378 /// TyIVar is used here to allow for variance (see the doc at
1381 /// Note: direct accesses to `ty` must also add dep edges.
1382 ty
: ivar
::TyIVar
<'tcx
, 'container
>
1385 /// The definition of an abstract data type - a struct or enum.
1387 /// These are all interned (by intern_adt_def) into the adt_defs
1390 /// Because of the possibility of nested tcx-s, this type
1391 /// needs 2 lifetimes: the traditional variant lifetime ('tcx)
1392 /// bounding the lifetime of the inner types is of course necessary.
1393 /// However, it is not sufficient - types from a child tcx must
1394 /// not be leaked into the master tcx by being stored in an AdtDefData.
1396 /// The 'container lifetime ensures that by outliving the container
1397 /// tcx and preventing shorter-lived types from being inserted. When
1398 /// write access is not needed, the 'container lifetime can be
1399 /// erased to 'static, which can be done by the AdtDef wrapper.
1400 pub struct AdtDefData
<'tcx
, 'container
: 'tcx
> {
1402 pub variants
: Vec
<VariantDefData
<'tcx
, 'container
>>,
1403 destructor
: Cell
<Option
<DefId
>>,
1404 flags
: Cell
<AdtFlags
>,
1407 impl<'tcx
, 'container
> PartialEq
for AdtDefData
<'tcx
, 'container
> {
1408 // AdtDefData are always interned and this is part of TyS equality
1410 fn eq(&self, other
: &Self) -> bool { self as *const _ == other as *const _ }
1413 impl<'tcx
, 'container
> Eq
for AdtDefData
<'tcx
, 'container
> {}
1415 impl<'tcx
, 'container
> Hash
for AdtDefData
<'tcx
, 'container
> {
1417 fn hash
<H
: Hasher
>(&self, s
: &mut H
) {
1418 (self as *const AdtDefData
).hash(s
)
1422 impl<'tcx
> Encodable
for AdtDef
<'tcx
> {
1423 fn encode
<S
: Encoder
>(&self, s
: &mut S
) -> Result
<(), S
::Error
> {
1428 impl<'tcx
> Decodable
for AdtDef
<'tcx
> {
1429 fn decode
<D
: Decoder
>(d
: &mut D
) -> Result
<AdtDef
<'tcx
>, D
::Error
> {
1430 let def_id
: DefId
= try
!{ Decodable::decode(d) }
;
1432 cstore
::tls
::with_decoding_context(d
, |dcx
, _
| {
1433 let def_id
= dcx
.translate_def_id(def_id
);
1434 Ok(dcx
.tcx().lookup_adt_def(def_id
))
1440 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
1441 pub enum AdtKind { Struct, Enum }
1443 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, RustcEncodable, RustcDecodable)]
1444 pub enum VariantKind { Struct, Tuple, Unit }
1447 pub fn from_variant_data(vdata
: &hir
::VariantData
) -> Self {
1449 hir
::VariantData
::Struct(..) => VariantKind
::Struct
,
1450 hir
::VariantData
::Tuple(..) => VariantKind
::Tuple
,
1451 hir
::VariantData
::Unit(..) => VariantKind
::Unit
,
1456 impl<'tcx
, 'container
> AdtDefData
<'tcx
, 'container
> {
1457 fn new(tcx
: &ctxt
<'tcx
>,
1460 variants
: Vec
<VariantDefData
<'tcx
, 'container
>>) -> Self {
1461 let mut flags
= AdtFlags
::NO_ADT_FLAGS
;
1462 let attrs
= tcx
.get_attrs(did
);
1463 if attr
::contains_name(&attrs
, "fundamental") {
1464 flags
= flags
| AdtFlags
::IS_FUNDAMENTAL
;
1466 if attr
::contains_name(&attrs
, "unsafe_no_drop_flag") {
1467 flags
= flags
| AdtFlags
::IS_NO_DROP_FLAG
;
1469 if tcx
.lookup_simd(did
) {
1470 flags
= flags
| AdtFlags
::IS_SIMD
;
1472 if Some(did
) == tcx
.lang_items
.phantom_data() {
1473 flags
= flags
| AdtFlags
::IS_PHANTOM_DATA
;
1475 if let AdtKind
::Enum
= kind
{
1476 flags
= flags
| AdtFlags
::IS_ENUM
;
1481 flags
: Cell
::new(flags
),
1482 destructor
: Cell
::new(None
)
1486 fn calculate_dtorck(&'tcx
self, tcx
: &ctxt
<'tcx
>) {
1487 if tcx
.is_adt_dtorck(self) {
1488 self.flags
.set(self.flags
.get() | AdtFlags
::IS_DTORCK
);
1490 self.flags
.set(self.flags
.get() | AdtFlags
::IS_DTORCK_VALID
)
1493 /// Returns the kind of the ADT - Struct or Enum.
1495 pub fn adt_kind(&self) -> AdtKind
{
1496 if self.flags
.get().intersects(AdtFlags
::IS_ENUM
) {
1503 /// Returns whether this is a dtorck type. If this returns
1504 /// true, this type being safe for destruction requires it to be
1505 /// alive; Otherwise, only the contents are required to be.
1507 pub fn is_dtorck(&'tcx
self, tcx
: &ctxt
<'tcx
>) -> bool
{
1508 if !self.flags
.get().intersects(AdtFlags
::IS_DTORCK_VALID
) {
1509 self.calculate_dtorck(tcx
)
1511 self.flags
.get().intersects(AdtFlags
::IS_DTORCK
)
1514 /// Returns whether this type is #[fundamental] for the purposes
1515 /// of coherence checking.
1517 pub fn is_fundamental(&self) -> bool
{
1518 self.flags
.get().intersects(AdtFlags
::IS_FUNDAMENTAL
)
1522 pub fn is_simd(&self) -> bool
{
1523 self.flags
.get().intersects(AdtFlags
::IS_SIMD
)
1526 /// Returns true if this is PhantomData<T>.
1528 pub fn is_phantom_data(&self) -> bool
{
1529 self.flags
.get().intersects(AdtFlags
::IS_PHANTOM_DATA
)
1532 /// Returns whether this type has a destructor.
1533 pub fn has_dtor(&self) -> bool
{
1534 match self.dtor_kind() {
1536 TraitDtor(..) => true
1540 /// Asserts this is a struct and returns the struct's unique
1542 pub fn struct_variant(&self) -> &VariantDefData
<'tcx
, 'container
> {
1543 assert
!(self.adt_kind() == AdtKind
::Struct
);
1548 pub fn type_scheme(&self, tcx
: &ctxt
<'tcx
>) -> TypeScheme
<'tcx
> {
1549 tcx
.lookup_item_type(self.did
)
1553 pub fn predicates(&self, tcx
: &ctxt
<'tcx
>) -> GenericPredicates
<'tcx
> {
1554 tcx
.lookup_predicates(self.did
)
1557 /// Returns an iterator over all fields contained
1560 pub fn all_fields(&self) ->
1562 slice
::Iter
<VariantDefData
<'tcx
, 'container
>>,
1563 slice
::Iter
<FieldDefData
<'tcx
, 'container
>>,
1564 for<'s
> fn(&'s VariantDefData
<'tcx
, 'container
>)
1565 -> slice
::Iter
<'s
, FieldDefData
<'tcx
, 'container
>>
1567 self.variants
.iter().flat_map(VariantDefData
::fields_iter
)
1571 pub fn is_empty(&self) -> bool
{
1572 self.variants
.is_empty()
1576 pub fn is_univariant(&self) -> bool
{
1577 self.variants
.len() == 1
1580 pub fn is_payloadfree(&self) -> bool
{
1581 !self.variants
.is_empty() &&
1582 self.variants
.iter().all(|v
| v
.fields
.is_empty())
1585 pub fn variant_with_id(&self, vid
: DefId
) -> &VariantDefData
<'tcx
, 'container
> {
1588 .find(|v
| v
.did
== vid
)
1589 .expect("variant_with_id: unknown variant")
1592 pub fn variant_index_with_id(&self, vid
: DefId
) -> usize {
1595 .position(|v
| v
.did
== vid
)
1596 .expect("variant_index_with_id: unknown variant")
1599 pub fn variant_of_def(&self, def
: Def
) -> &VariantDefData
<'tcx
, 'container
> {
1601 Def
::Variant(_
, vid
) => self.variant_with_id(vid
),
1602 Def
::Struct(..) | Def
::TyAlias(..) => self.struct_variant(),
1603 _
=> panic
!("unexpected def {:?} in variant_of_def", def
)
1607 pub fn destructor(&self) -> Option
<DefId
> {
1608 self.destructor
.get()
1611 pub fn set_destructor(&self, dtor
: DefId
) {
1612 self.destructor
.set(Some(dtor
));
1615 pub fn dtor_kind(&self) -> DtorKind
{
1616 match self.destructor
.get() {
1618 TraitDtor(!self.flags
.get().intersects(AdtFlags
::IS_NO_DROP_FLAG
))
1625 impl<'tcx
, 'container
> VariantDefData
<'tcx
, 'container
> {
1627 fn fields_iter(&self) -> slice
::Iter
<FieldDefData
<'tcx
, 'container
>> {
1631 pub fn kind(&self) -> VariantKind
{
1635 pub fn is_tuple_struct(&self) -> bool
{
1636 self.kind() == VariantKind
::Tuple
1640 pub fn find_field_named(&self,
1642 -> Option
<&FieldDefData
<'tcx
, 'container
>> {
1643 self.fields
.iter().find(|f
| f
.name
== name
)
1647 pub fn index_of_field_named(&self,
1650 self.fields
.iter().position(|f
| f
.name
== name
)
1654 pub fn field_named(&self, name
: ast
::Name
) -> &FieldDefData
<'tcx
, 'container
> {
1655 self.find_field_named(name
).unwrap()
1659 impl<'tcx
, 'container
> FieldDefData
<'tcx
, 'container
> {
1660 pub fn new(did
: DefId
,
1662 vis
: hir
::Visibility
) -> Self {
1667 ty
: ivar
::TyIVar
::new()
1671 pub fn ty(&self, tcx
: &ctxt
<'tcx
>, subst
: &Substs
<'tcx
>) -> Ty
<'tcx
> {
1672 self.unsubst_ty().subst(tcx
, subst
)
1675 pub fn unsubst_ty(&self) -> Ty
<'tcx
> {
1676 self.ty
.unwrap(DepNode
::FieldTy(self.did
))
1679 pub fn fulfill_ty(&self, ty
: Ty
<'container
>) {
1680 self.ty
.fulfill(DepNode
::FieldTy(self.did
), ty
);
1684 /// Records the substitutions used to translate the polytype for an
1685 /// item into the monotype of an item reference.
1687 pub struct ItemSubsts
<'tcx
> {
1688 pub substs
: Substs
<'tcx
>,
1691 #[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq, Debug, RustcEncodable, RustcDecodable)]
1692 pub enum ClosureKind
{
1693 // Warning: Ordering is significant here! The ordering is chosen
1694 // because the trait Fn is a subtrait of FnMut and so in turn, and
1695 // hence we order it so that Fn < FnMut < FnOnce.
1702 pub fn trait_did(&self, cx
: &ctxt
) -> DefId
{
1703 let result
= match *self {
1704 FnClosureKind
=> cx
.lang_items
.require(FnTraitLangItem
),
1705 FnMutClosureKind
=> {
1706 cx
.lang_items
.require(FnMutTraitLangItem
)
1708 FnOnceClosureKind
=> {
1709 cx
.lang_items
.require(FnOnceTraitLangItem
)
1713 Ok(trait_did
) => trait_did
,
1714 Err(err
) => cx
.sess
.fatal(&err
[..]),
1718 /// True if this a type that impls this closure kind
1719 /// must also implement `other`.
1720 pub fn extends(self, other
: ty
::ClosureKind
) -> bool
{
1721 match (self, other
) {
1722 (FnClosureKind
, FnClosureKind
) => true,
1723 (FnClosureKind
, FnMutClosureKind
) => true,
1724 (FnClosureKind
, FnOnceClosureKind
) => true,
1725 (FnMutClosureKind
, FnMutClosureKind
) => true,
1726 (FnMutClosureKind
, FnOnceClosureKind
) => true,
1727 (FnOnceClosureKind
, FnOnceClosureKind
) => true,
1733 impl<'tcx
> TyS
<'tcx
> {
1734 /// Iterator that walks `self` and any types reachable from
1735 /// `self`, in depth-first order. Note that just walks the types
1736 /// that appear in `self`, it does not descend into the fields of
1737 /// structs or variants. For example:
1740 /// isize => { isize }
1741 /// Foo<Bar<isize>> => { Foo<Bar<isize>>, Bar<isize>, isize }
1742 /// [isize] => { [isize], isize }
1744 pub fn walk(&'tcx
self) -> TypeWalker
<'tcx
> {
1745 TypeWalker
::new(self)
1748 /// Iterator that walks the immediate children of `self`. Hence
1749 /// `Foo<Bar<i32>, u32>` yields the sequence `[Bar<i32>, u32]`
1750 /// (but not `i32`, like `walk`).
1751 pub fn walk_shallow(&'tcx
self) -> IntoIter
<Ty
<'tcx
>> {
1752 walk
::walk_shallow(self)
1755 /// Walks `ty` and any types appearing within `ty`, invoking the
1756 /// callback `f` on each type. If the callback returns false, then the
1757 /// children of the current type are ignored.
1759 /// Note: prefer `ty.walk()` where possible.
1760 pub fn maybe_walk
<F
>(&'tcx
self, mut f
: F
)
1761 where F
: FnMut(Ty
<'tcx
>) -> bool
1763 let mut walker
= self.walk();
1764 while let Some(ty
) = walker
.next() {
1766 walker
.skip_current_subtree();
1772 impl<'tcx
> ItemSubsts
<'tcx
> {
1773 pub fn empty() -> ItemSubsts
<'tcx
> {
1774 ItemSubsts { substs: Substs::empty() }
1777 pub fn is_noop(&self) -> bool
{
1778 self.substs
.is_noop()
1782 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
1783 pub enum LvaluePreference
{
1788 impl LvaluePreference
{
1789 pub fn from_mutbl(m
: hir
::Mutability
) -> Self {
1791 hir
::MutMutable
=> PreferMutLvalue
,
1792 hir
::MutImmutable
=> NoPreference
,
1797 /// Helper for looking things up in the various maps that are populated during
1798 /// typeck::collect (e.g., `cx.impl_or_trait_items`, `cx.tcache`, etc). All of
1799 /// these share the pattern that if the id is local, it should have been loaded
1800 /// into the map by the `typeck::collect` phase. If the def-id is external,
1801 /// then we have to go consult the crate loading code (and cache the result for
1803 fn lookup_locally_or_in_crate_store
<M
, F
>(descr
: &str,
1808 M
: MemoizationMap
<Key
=DefId
>,
1809 F
: FnOnce() -> M
::Value
,
1811 map
.memoize(def_id
, || {
1812 if def_id
.is_local() {
1813 panic
!("No def'n found for {:?} in tcx.{}", def_id
, descr
);
1820 pub fn from_mutbl(m
: hir
::Mutability
) -> BorrowKind
{
1822 hir
::MutMutable
=> MutBorrow
,
1823 hir
::MutImmutable
=> ImmBorrow
,
1827 /// Returns a mutability `m` such that an `&m T` pointer could be used to obtain this borrow
1828 /// kind. Because borrow kinds are richer than mutabilities, we sometimes have to pick a
1829 /// mutability that is stronger than necessary so that it at least *would permit* the borrow in
1831 pub fn to_mutbl_lossy(self) -> hir
::Mutability
{
1833 MutBorrow
=> hir
::MutMutable
,
1834 ImmBorrow
=> hir
::MutImmutable
,
1836 // We have no type corresponding to a unique imm borrow, so
1837 // use `&mut`. It gives all the capabilities of an `&uniq`
1838 // and hence is a safe "over approximation".
1839 UniqueImmBorrow
=> hir
::MutMutable
,
1843 pub fn to_user_str(&self) -> &'
static str {
1845 MutBorrow
=> "mutable",
1846 ImmBorrow
=> "immutable",
1847 UniqueImmBorrow
=> "uniquely immutable",
1852 impl<'tcx
> ctxt
<'tcx
> {
1853 pub fn node_id_to_type(&self, id
: NodeId
) -> Ty
<'tcx
> {
1854 match self.node_id_to_type_opt(id
) {
1856 None
=> self.sess
.bug(
1857 &format
!("node_id_to_type: no type for node `{}`",
1858 self.map
.node_to_string(id
)))
1862 pub fn node_id_to_type_opt(&self, id
: NodeId
) -> Option
<Ty
<'tcx
>> {
1863 self.tables
.borrow().node_types
.get(&id
).cloned()
1866 pub fn node_id_item_substs(&self, id
: NodeId
) -> ItemSubsts
<'tcx
> {
1867 match self.tables
.borrow().item_substs
.get(&id
) {
1868 None
=> ItemSubsts
::empty(),
1869 Some(ts
) => ts
.clone(),
1873 // Returns the type of a pattern as a monotype. Like @expr_ty, this function
1874 // doesn't provide type parameter substitutions.
1875 pub fn pat_ty(&self, pat
: &hir
::Pat
) -> Ty
<'tcx
> {
1876 self.node_id_to_type(pat
.id
)
1878 pub fn pat_ty_opt(&self, pat
: &hir
::Pat
) -> Option
<Ty
<'tcx
>> {
1879 self.node_id_to_type_opt(pat
.id
)
1882 // Returns the type of an expression as a monotype.
1884 // NB (1): This is the PRE-ADJUSTMENT TYPE for the expression. That is, in
1885 // some cases, we insert `AutoAdjustment` annotations such as auto-deref or
1886 // auto-ref. The type returned by this function does not consider such
1887 // adjustments. See `expr_ty_adjusted()` instead.
1889 // NB (2): This type doesn't provide type parameter substitutions; e.g. if you
1890 // ask for the type of "id" in "id(3)", it will return "fn(&isize) -> isize"
1891 // instead of "fn(ty) -> T with T = isize".
1892 pub fn expr_ty(&self, expr
: &hir
::Expr
) -> Ty
<'tcx
> {
1893 self.node_id_to_type(expr
.id
)
1896 pub fn expr_ty_opt(&self, expr
: &hir
::Expr
) -> Option
<Ty
<'tcx
>> {
1897 self.node_id_to_type_opt(expr
.id
)
1900 /// Returns the type of `expr`, considering any `AutoAdjustment`
1901 /// entry recorded for that expression.
1903 /// It would almost certainly be better to store the adjusted ty in with
1904 /// the `AutoAdjustment`, but I opted not to do this because it would
1905 /// require serializing and deserializing the type and, although that's not
1906 /// hard to do, I just hate that code so much I didn't want to touch it
1907 /// unless it was to fix it properly, which seemed a distraction from the
1908 /// thread at hand! -nmatsakis
1909 pub fn expr_ty_adjusted(&self, expr
: &hir
::Expr
) -> Ty
<'tcx
> {
1911 .adjust(self, expr
.span
, expr
.id
,
1912 self.tables
.borrow().adjustments
.get(&expr
.id
),
1914 self.tables
.borrow().method_map
.get(&method_call
).map(|method
| method
.ty
)
1918 pub fn expr_ty_adjusted_opt(&self, expr
: &hir
::Expr
) -> Option
<Ty
<'tcx
>> {
1919 self.expr_ty_opt(expr
).map(|t
| t
.adjust(self,
1922 self.tables
.borrow().adjustments
.get(&expr
.id
),
1924 self.tables
.borrow().method_map
.get(&method_call
).map(|method
| method
.ty
)
1928 pub fn expr_span(&self, id
: NodeId
) -> Span
{
1929 match self.map
.find(id
) {
1930 Some(ast_map
::NodeExpr(e
)) => {
1934 self.sess
.bug(&format
!("Node id {} is not an expr: {:?}",
1938 self.sess
.bug(&format
!("Node id {} is not present \
1939 in the node map", id
));
1944 pub fn local_var_name_str(&self, id
: NodeId
) -> InternedString
{
1945 match self.map
.find(id
) {
1946 Some(ast_map
::NodeLocal(pat
)) => {
1948 PatKind
::Ident(_
, ref path1
, _
) => path1
.node
.name
.as_str(),
1950 self.sess
.bug(&format
!("Variable id {} maps to {:?}, not local", id
, pat
));
1954 r
=> self.sess
.bug(&format
!("Variable id {} maps to {:?}, not local", id
, r
)),
1958 pub fn resolve_expr(&self, expr
: &hir
::Expr
) -> Def
{
1959 match self.def_map
.borrow().get(&expr
.id
) {
1960 Some(def
) => def
.full_def(),
1962 self.sess
.span_bug(expr
.span
, &format
!(
1963 "no def-map entry for expr {}", expr
.id
));
1968 pub fn expr_is_lval(&self, expr
: &hir
::Expr
) -> bool
{
1970 hir
::ExprPath(..) => {
1971 // We can't use resolve_expr here, as this needs to run on broken
1972 // programs. We don't need to through - associated items are all
1974 match self.def_map
.borrow().get(&expr
.id
) {
1975 Some(&def
::PathResolution
{
1976 base_def
: Def
::Static(..), ..
1977 }) | Some(&def
::PathResolution
{
1978 base_def
: Def
::Upvar(..), ..
1979 }) | Some(&def
::PathResolution
{
1980 base_def
: Def
::Local(..), ..
1984 Some(&def
::PathResolution { base_def: Def::Err, .. }
)=> true,
1986 None
=> self.sess
.span_bug(expr
.span
, &format
!(
1987 "no def for path {}", expr
.id
))
1991 hir
::ExprType(ref e
, _
) => {
1992 self.expr_is_lval(e
)
1995 hir
::ExprUnary(hir
::UnDeref
, _
) |
1996 hir
::ExprField(..) |
1997 hir
::ExprTupField(..) |
1998 hir
::ExprIndex(..) => {
2003 hir
::ExprMethodCall(..) |
2004 hir
::ExprStruct(..) |
2005 hir
::ExprRange(..) |
2008 hir
::ExprMatch(..) |
2009 hir
::ExprClosure(..) |
2010 hir
::ExprBlock(..) |
2011 hir
::ExprRepeat(..) |
2013 hir
::ExprBreak(..) |
2014 hir
::ExprAgain(..) |
2016 hir
::ExprWhile(..) |
2018 hir
::ExprAssign(..) |
2019 hir
::ExprInlineAsm(..) |
2020 hir
::ExprAssignOp(..) |
2022 hir
::ExprUnary(..) |
2024 hir
::ExprAddrOf(..) |
2025 hir
::ExprBinary(..) |
2026 hir
::ExprCast(..) => {
2032 pub fn provided_trait_methods(&self, id
: DefId
) -> Vec
<Rc
<Method
<'tcx
>>> {
2033 if let Some(id
) = self.map
.as_local_node_id(id
) {
2034 if let ItemTrait(_
, _
, _
, ref ms
) = self.map
.expect_item(id
).node
{
2035 ms
.iter().filter_map(|ti
| {
2036 if let hir
::MethodTraitItem(_
, Some(_
)) = ti
.node
{
2037 match self.impl_or_trait_item(self.map
.local_def_id(ti
.id
)) {
2038 MethodTraitItem(m
) => Some(m
),
2040 self.sess
.bug("provided_trait_methods(): \
2041 non-method item found from \
2042 looking up provided method?!")
2050 self.sess
.bug(&format
!("provided_trait_methods: `{:?}` is not a trait", id
))
2053 self.sess
.cstore
.provided_trait_methods(self, id
)
2057 pub fn associated_consts(&self, id
: DefId
) -> Vec
<Rc
<AssociatedConst
<'tcx
>>> {
2058 if let Some(id
) = self.map
.as_local_node_id(id
) {
2059 match self.map
.expect_item(id
).node
{
2060 ItemTrait(_
, _
, _
, ref tis
) => {
2061 tis
.iter().filter_map(|ti
| {
2062 if let hir
::ConstTraitItem(_
, _
) = ti
.node
{
2063 match self.impl_or_trait_item(self.map
.local_def_id(ti
.id
)) {
2064 ConstTraitItem(ac
) => Some(ac
),
2066 self.sess
.bug("associated_consts(): \
2067 non-const item found from \
2068 looking up a constant?!")
2076 ItemImpl(_
, _
, _
, _
, _
, ref iis
) => {
2077 iis
.iter().filter_map(|ii
| {
2078 if let hir
::ImplItemKind
::Const(_
, _
) = ii
.node
{
2079 match self.impl_or_trait_item(self.map
.local_def_id(ii
.id
)) {
2080 ConstTraitItem(ac
) => Some(ac
),
2082 self.sess
.bug("associated_consts(): \
2083 non-const item found from \
2084 looking up a constant?!")
2093 self.sess
.bug(&format
!("associated_consts: `{:?}` is not a trait \
2098 self.sess
.cstore
.associated_consts(self, id
)
2102 pub fn trait_impl_polarity(&self, id
: DefId
) -> Option
<hir
::ImplPolarity
> {
2103 if let Some(id
) = self.map
.as_local_node_id(id
) {
2104 match self.map
.find(id
) {
2105 Some(ast_map
::NodeItem(item
)) => {
2107 hir
::ItemImpl(_
, polarity
, _
, _
, _
, _
) => Some(polarity
),
2114 self.sess
.cstore
.impl_polarity(id
)
2118 pub fn custom_coerce_unsized_kind(&self, did
: DefId
) -> adjustment
::CustomCoerceUnsized
{
2119 self.custom_coerce_unsized_kinds
.memoize(did
, || {
2120 let (kind
, src
) = if did
.krate
!= LOCAL_CRATE
{
2121 (self.sess
.cstore
.custom_coerce_unsized_kind(did
), "external")
2129 self.sess
.bug(&format
!("custom_coerce_unsized_kind: \
2130 {} impl `{}` is missing its kind",
2131 src
, self.item_path_str(did
)));
2137 pub fn impl_or_trait_item(&self, id
: DefId
) -> ImplOrTraitItem
<'tcx
> {
2138 lookup_locally_or_in_crate_store(
2139 "impl_or_trait_items", id
, &self.impl_or_trait_items
,
2140 || self.sess
.cstore
.impl_or_trait_item(self, id
))
2143 pub fn trait_item_def_ids(&self, id
: DefId
) -> Rc
<Vec
<ImplOrTraitItemId
>> {
2144 lookup_locally_or_in_crate_store(
2145 "trait_item_def_ids", id
, &self.trait_item_def_ids
,
2146 || Rc
::new(self.sess
.cstore
.trait_item_def_ids(id
)))
2149 /// Returns the trait-ref corresponding to a given impl, or None if it is
2150 /// an inherent impl.
2151 pub fn impl_trait_ref(&self, id
: DefId
) -> Option
<TraitRef
<'tcx
>> {
2152 lookup_locally_or_in_crate_store(
2153 "impl_trait_refs", id
, &self.impl_trait_refs
,
2154 || self.sess
.cstore
.impl_trait_ref(self, id
))
2157 /// Returns whether this DefId refers to an impl
2158 pub fn is_impl(&self, id
: DefId
) -> bool
{
2159 if let Some(id
) = self.map
.as_local_node_id(id
) {
2160 if let Some(ast_map
::NodeItem(
2161 &hir
::Item { node: hir::ItemImpl(..), .. }
)) = self.map
.find(id
) {
2167 self.sess
.cstore
.is_impl(id
)
2171 pub fn trait_ref_to_def_id(&self, tr
: &hir
::TraitRef
) -> DefId
{
2172 self.def_map
.borrow().get(&tr
.ref_id
).expect("no def-map entry for trait").def_id()
2175 pub fn item_path_str(&self, id
: DefId
) -> String
{
2176 self.with_path(id
, |path
| ast_map
::path_to_string(path
))
2179 pub fn def_path(&self, id
: DefId
) -> ast_map
::DefPath
{
2181 self.map
.def_path(id
)
2183 self.sess
.cstore
.def_path(id
)
2187 pub fn with_path
<T
, F
>(&self, id
: DefId
, f
: F
) -> T
where
2188 F
: FnOnce(ast_map
::PathElems
) -> T
,
2190 if let Some(id
) = self.map
.as_local_node_id(id
) {
2191 self.map
.with_path(id
, f
)
2193 f(self.sess
.cstore
.item_path(id
).iter().cloned().chain(LinkedPath
::empty()))
2197 pub fn item_name(&self, id
: DefId
) -> ast
::Name
{
2198 if let Some(id
) = self.map
.as_local_node_id(id
) {
2199 self.map
.get_path_elem(id
).name()
2201 self.sess
.cstore
.item_name(id
)
2205 // Register a given item type
2206 pub fn register_item_type(&self, did
: DefId
, ty
: TypeScheme
<'tcx
>) {
2207 self.tcache
.borrow_mut().insert(did
, ty
);
2210 // If the given item is in an external crate, looks up its type and adds it to
2211 // the type cache. Returns the type parameters and type.
2212 pub fn lookup_item_type(&self, did
: DefId
) -> TypeScheme
<'tcx
> {
2213 lookup_locally_or_in_crate_store(
2214 "tcache", did
, &self.tcache
,
2215 || self.sess
.cstore
.item_type(self, did
))
2218 /// Given the did of a trait, returns its canonical trait ref.
2219 pub fn lookup_trait_def(&self, did
: DefId
) -> &'tcx TraitDef
<'tcx
> {
2220 lookup_locally_or_in_crate_store(
2221 "trait_defs", did
, &self.trait_defs
,
2222 || self.alloc_trait_def(self.sess
.cstore
.trait_def(self, did
))
2226 /// Given the did of an ADT, return a master reference to its
2227 /// definition. Unless you are planning on fulfilling the ADT's fields,
2228 /// use lookup_adt_def instead.
2229 pub fn lookup_adt_def_master(&self, did
: DefId
) -> AdtDefMaster
<'tcx
> {
2230 lookup_locally_or_in_crate_store(
2231 "adt_defs", did
, &self.adt_defs
,
2232 || self.sess
.cstore
.adt_def(self, did
)
2236 /// Given the did of an ADT, return a reference to its definition.
2237 pub fn lookup_adt_def(&self, did
: DefId
) -> AdtDef
<'tcx
> {
2238 // when reverse-variance goes away, a transmute::<AdtDefMaster,AdtDef>
2239 // would be needed here.
2240 self.lookup_adt_def_master(did
)
2243 /// Given the did of an item, returns its full set of predicates.
2244 pub fn lookup_predicates(&self, did
: DefId
) -> GenericPredicates
<'tcx
> {
2245 lookup_locally_or_in_crate_store(
2246 "predicates", did
, &self.predicates
,
2247 || self.sess
.cstore
.item_predicates(self, did
))
2250 /// Given the did of a trait, returns its superpredicates.
2251 pub fn lookup_super_predicates(&self, did
: DefId
) -> GenericPredicates
<'tcx
> {
2252 lookup_locally_or_in_crate_store(
2253 "super_predicates", did
, &self.super_predicates
,
2254 || self.sess
.cstore
.item_super_predicates(self, did
))
2257 /// If `type_needs_drop` returns true, then `ty` is definitely
2258 /// non-copy and *might* have a destructor attached; if it returns
2259 /// false, then `ty` definitely has no destructor (i.e. no drop glue).
2261 /// (Note that this implies that if `ty` has a destructor attached,
2262 /// then `type_needs_drop` will definitely return `true` for `ty`.)
2263 pub fn type_needs_drop_given_env
<'a
>(&self,
2265 param_env
: &ty
::ParameterEnvironment
<'a
,'tcx
>) -> bool
{
2266 // Issue #22536: We first query type_moves_by_default. It sees a
2267 // normalized version of the type, and therefore will definitely
2268 // know whether the type implements Copy (and thus needs no
2269 // cleanup/drop/zeroing) ...
2270 let implements_copy
= !ty
.moves_by_default(param_env
, DUMMY_SP
);
2272 if implements_copy { return false; }
2274 // ... (issue #22536 continued) but as an optimization, still use
2275 // prior logic of asking if the `needs_drop` bit is set; we need
2276 // not zero non-Copy types if they have no destructor.
2278 // FIXME(#22815): Note that calling `ty::type_contents` is a
2279 // conservative heuristic; it may report that `needs_drop` is set
2280 // when actual type does not actually have a destructor associated
2281 // with it. But since `ty` absolutely did not have the `Copy`
2282 // bound attached (see above), it is sound to treat it as having a
2283 // destructor (e.g. zero its memory on move).
2285 let contents
= ty
.type_contents(self);
2286 debug
!("type_needs_drop ty={:?} contents={:?}", ty
, contents
);
2287 contents
.needs_drop(self)
2290 /// Get the attributes of a definition.
2291 pub fn get_attrs(&self, did
: DefId
) -> Cow
<'tcx
, [ast
::Attribute
]> {
2292 if let Some(id
) = self.map
.as_local_node_id(did
) {
2293 Cow
::Borrowed(self.map
.attrs(id
))
2295 Cow
::Owned(self.sess
.cstore
.item_attrs(did
))
2299 /// Determine whether an item is annotated with an attribute
2300 pub fn has_attr(&self, did
: DefId
, attr
: &str) -> bool
{
2301 self.get_attrs(did
).iter().any(|item
| item
.check_name(attr
))
2304 /// Determine whether an item is annotated with `#[repr(packed)]`
2305 pub fn lookup_packed(&self, did
: DefId
) -> bool
{
2306 self.lookup_repr_hints(did
).contains(&attr
::ReprPacked
)
2309 /// Determine whether an item is annotated with `#[simd]`
2310 pub fn lookup_simd(&self, did
: DefId
) -> bool
{
2311 self.has_attr(did
, "simd")
2312 || self.lookup_repr_hints(did
).contains(&attr
::ReprSimd
)
2315 pub fn item_variances(&self, item_id
: DefId
) -> Rc
<ItemVariances
> {
2316 lookup_locally_or_in_crate_store(
2317 "item_variance_map", item_id
, &self.item_variance_map
,
2318 || Rc
::new(self.sess
.cstore
.item_variances(item_id
)))
2321 pub fn trait_has_default_impl(&self, trait_def_id
: DefId
) -> bool
{
2322 self.populate_implementations_for_trait_if_necessary(trait_def_id
);
2324 let def
= self.lookup_trait_def(trait_def_id
);
2325 def
.flags
.get().intersects(TraitFlags
::HAS_DEFAULT_IMPL
)
2328 /// Records a trait-to-implementation mapping.
2329 pub fn record_trait_has_default_impl(&self, trait_def_id
: DefId
) {
2330 let def
= self.lookup_trait_def(trait_def_id
);
2331 def
.flags
.set(def
.flags
.get() | TraitFlags
::HAS_DEFAULT_IMPL
)
2334 /// Load primitive inherent implementations if necessary
2335 pub fn populate_implementations_for_primitive_if_necessary(&self,
2336 primitive_def_id
: DefId
) {
2337 if primitive_def_id
.is_local() {
2341 // The primitive is not local, hence we are reading this out
2343 let _ignore
= self.dep_graph
.in_ignore();
2345 if self.populated_external_primitive_impls
.borrow().contains(&primitive_def_id
) {
2349 debug
!("populate_implementations_for_primitive_if_necessary: searching for {:?}",
2352 let impl_items
= self.sess
.cstore
.impl_items(primitive_def_id
);
2354 // Store the implementation info.
2355 self.impl_items
.borrow_mut().insert(primitive_def_id
, impl_items
);
2356 self.populated_external_primitive_impls
.borrow_mut().insert(primitive_def_id
);
2359 /// Populates the type context with all the inherent implementations for
2360 /// the given type if necessary.
2361 pub fn populate_inherent_implementations_for_type_if_necessary(&self,
2363 if type_id
.is_local() {
2367 // The type is not local, hence we are reading this out of
2368 // metadata and don't need to track edges.
2369 let _ignore
= self.dep_graph
.in_ignore();
2371 if self.populated_external_types
.borrow().contains(&type_id
) {
2375 debug
!("populate_inherent_implementations_for_type_if_necessary: searching for {:?}",
2378 let inherent_impls
= self.sess
.cstore
.inherent_implementations_for_type(type_id
);
2379 for &impl_def_id
in &inherent_impls
{
2380 // Store the implementation info.
2381 let impl_items
= self.sess
.cstore
.impl_items(impl_def_id
);
2382 self.impl_items
.borrow_mut().insert(impl_def_id
, impl_items
);
2385 self.inherent_impls
.borrow_mut().insert(type_id
, Rc
::new(inherent_impls
));
2386 self.populated_external_types
.borrow_mut().insert(type_id
);
2389 /// Populates the type context with all the implementations for the given
2390 /// trait if necessary.
2391 pub fn populate_implementations_for_trait_if_necessary(&self, trait_id
: DefId
) {
2392 if trait_id
.is_local() {
2396 // The type is not local, hence we are reading this out of
2397 // metadata and don't need to track edges.
2398 let _ignore
= self.dep_graph
.in_ignore();
2400 let def
= self.lookup_trait_def(trait_id
);
2401 if def
.flags
.get().intersects(TraitFlags
::IMPLS_VALID
) {
2405 debug
!("populate_implementations_for_trait_if_necessary: searching for {:?}", def
);
2407 if self.sess
.cstore
.is_defaulted_trait(trait_id
) {
2408 self.record_trait_has_default_impl(trait_id
);
2411 for impl_def_id
in self.sess
.cstore
.implementations_of_trait(trait_id
) {
2412 let impl_items
= self.sess
.cstore
.impl_items(impl_def_id
);
2413 let trait_ref
= self.impl_trait_ref(impl_def_id
).unwrap();
2414 // Record the trait->implementation mapping.
2415 def
.record_impl(self, impl_def_id
, trait_ref
);
2417 // For any methods that use a default implementation, add them to
2418 // the map. This is a bit unfortunate.
2419 for impl_item_def_id
in &impl_items
{
2420 let method_def_id
= impl_item_def_id
.def_id();
2421 // load impl items eagerly for convenience
2422 // FIXME: we may want to load these lazily
2423 self.impl_or_trait_item(method_def_id
);
2426 // Store the implementation info.
2427 self.impl_items
.borrow_mut().insert(impl_def_id
, impl_items
);
2430 def
.flags
.set(def
.flags
.get() | TraitFlags
::IMPLS_VALID
);
2433 pub fn closure_kind(&self, def_id
: DefId
) -> ty
::ClosureKind
{
2434 Tables
::closure_kind(&self.tables
, self, def_id
)
2437 pub fn closure_type(&self,
2439 substs
: &ClosureSubsts
<'tcx
>)
2440 -> ty
::ClosureTy
<'tcx
>
2442 Tables
::closure_type(&self.tables
, self, def_id
, substs
)
2445 /// Given the def_id of an impl, return the def_id of the trait it implements.
2446 /// If it implements no trait, return `None`.
2447 pub fn trait_id_of_impl(&self, def_id
: DefId
) -> Option
<DefId
> {
2448 self.impl_trait_ref(def_id
).map(|tr
| tr
.def_id
)
2451 /// If the given def ID describes a method belonging to an impl, return the
2452 /// ID of the impl that the method belongs to. Otherwise, return `None`.
2453 pub fn impl_of_method(&self, def_id
: DefId
) -> Option
<DefId
> {
2454 if def_id
.krate
!= LOCAL_CRATE
{
2455 return match self.sess
.cstore
.impl_or_trait_item(self, def_id
).container() {
2456 TraitContainer(_
) => None
,
2457 ImplContainer(def_id
) => Some(def_id
),
2460 match self.impl_or_trait_items
.borrow().get(&def_id
).cloned() {
2461 Some(trait_item
) => {
2462 match trait_item
.container() {
2463 TraitContainer(_
) => None
,
2464 ImplContainer(def_id
) => Some(def_id
),
2471 /// If the given def ID describes an item belonging to a trait (either a
2472 /// default method or an implementation of a trait method), return the ID of
2473 /// the trait that the method belongs to. Otherwise, return `None`.
2474 pub fn trait_of_item(&self, def_id
: DefId
) -> Option
<DefId
> {
2475 if def_id
.krate
!= LOCAL_CRATE
{
2476 return self.sess
.cstore
.trait_of_item(self, def_id
);
2478 match self.impl_or_trait_items
.borrow().get(&def_id
).cloned() {
2479 Some(impl_or_trait_item
) => {
2480 match impl_or_trait_item
.container() {
2481 TraitContainer(def_id
) => Some(def_id
),
2482 ImplContainer(def_id
) => self.trait_id_of_impl(def_id
),
2489 /// If the given def ID describes an item belonging to a trait, (either a
2490 /// default method or an implementation of a trait method), return the ID of
2491 /// the method inside trait definition (this means that if the given def ID
2492 /// is already that of the original trait method, then the return value is
2494 /// Otherwise, return `None`.
2495 pub fn trait_item_of_item(&self, def_id
: DefId
) -> Option
<ImplOrTraitItemId
> {
2496 let impl_item
= match self.impl_or_trait_items
.borrow().get(&def_id
) {
2497 Some(m
) => m
.clone(),
2498 None
=> return None
,
2500 let name
= impl_item
.name();
2501 match self.trait_of_item(def_id
) {
2502 Some(trait_did
) => {
2503 self.trait_items(trait_did
).iter()
2504 .find(|item
| item
.name() == name
)
2505 .map(|item
| item
.id())
2511 /// Construct a parameter environment suitable for static contexts or other contexts where there
2512 /// are no free type/lifetime parameters in scope.
2513 pub fn empty_parameter_environment
<'a
>(&'a
self)
2514 -> ParameterEnvironment
<'a
,'tcx
> {
2516 // for an empty parameter environment, there ARE no free
2517 // regions, so it shouldn't matter what we use for the free id
2518 let free_id_outlive
= self.region_maps
.node_extent(ast
::DUMMY_NODE_ID
);
2519 ty
::ParameterEnvironment
{ tcx
: self,
2520 free_substs
: Substs
::empty(),
2521 caller_bounds
: Vec
::new(),
2522 implicit_region_bound
: ty
::ReEmpty
,
2523 selection_cache
: traits
::SelectionCache
::new(),
2524 evaluation_cache
: traits
::EvaluationCache
::new(),
2525 free_id_outlive
: free_id_outlive
}
2528 /// Constructs and returns a substitution that can be applied to move from
2529 /// the "outer" view of a type or method to the "inner" view.
2530 /// In general, this means converting from bound parameters to
2531 /// free parameters. Since we currently represent bound/free type
2532 /// parameters in the same way, this only has an effect on regions.
2533 pub fn construct_free_substs(&self, generics
: &Generics
<'tcx
>,
2534 free_id_outlive
: CodeExtent
) -> Substs
<'tcx
> {
2536 let mut types
= VecPerParamSpace
::empty();
2537 for def
in generics
.types
.as_slice() {
2538 debug
!("construct_parameter_environment(): push_types_from_defs: def={:?}",
2540 types
.push(def
.space
, self.mk_param_from_def(def
));
2543 // map bound 'a => free 'a
2544 let mut regions
= VecPerParamSpace
::empty();
2545 for def
in generics
.regions
.as_slice() {
2547 ReFree(FreeRegion
{ scope
: free_id_outlive
,
2548 bound_region
: BrNamed(def
.def_id
, def
.name
) });
2549 debug
!("push_region_params {:?}", region
);
2550 regions
.push(def
.space
, region
);
2555 regions
: subst
::NonerasedRegions(regions
)
2559 /// See `ParameterEnvironment` struct def'n for details.
2560 /// If you were using `free_id: NodeId`, you might try `self.region_maps.item_extent(free_id)`
2561 /// for the `free_id_outlive` parameter. (But note that that is not always quite right.)
2562 pub fn construct_parameter_environment
<'a
>(&'a
self,
2564 generics
: &ty
::Generics
<'tcx
>,
2565 generic_predicates
: &ty
::GenericPredicates
<'tcx
>,
2566 free_id_outlive
: CodeExtent
)
2567 -> ParameterEnvironment
<'a
, 'tcx
>
2570 // Construct the free substs.
2573 let free_substs
= self.construct_free_substs(generics
, free_id_outlive
);
2576 // Compute the bounds on Self and the type parameters.
2579 let bounds
= generic_predicates
.instantiate(self, &free_substs
);
2580 let bounds
= self.liberate_late_bound_regions(free_id_outlive
, &ty
::Binder(bounds
));
2581 let predicates
= bounds
.predicates
.into_vec();
2583 // Finally, we have to normalize the bounds in the environment, in
2584 // case they contain any associated type projections. This process
2585 // can yield errors if the put in illegal associated types, like
2586 // `<i32 as Foo>::Bar` where `i32` does not implement `Foo`. We
2587 // report these errors right here; this doesn't actually feel
2588 // right to me, because constructing the environment feels like a
2589 // kind of a "idempotent" action, but I'm not sure where would be
2590 // a better place. In practice, we construct environments for
2591 // every fn once during type checking, and we'll abort if there
2592 // are any errors at that point, so after type checking you can be
2593 // sure that this will succeed without errors anyway.
2596 let unnormalized_env
= ty
::ParameterEnvironment
{
2598 free_substs
: free_substs
,
2599 implicit_region_bound
: ty
::ReScope(free_id_outlive
),
2600 caller_bounds
: predicates
,
2601 selection_cache
: traits
::SelectionCache
::new(),
2602 evaluation_cache
: traits
::EvaluationCache
::new(),
2603 free_id_outlive
: free_id_outlive
,
2606 let cause
= traits
::ObligationCause
::misc(span
, free_id_outlive
.node_id(&self.region_maps
));
2607 traits
::normalize_param_env_or_error(unnormalized_env
, cause
)
2610 pub fn is_method_call(&self, expr_id
: NodeId
) -> bool
{
2611 self.tables
.borrow().method_map
.contains_key(&MethodCall
::expr(expr_id
))
2614 pub fn is_overloaded_autoderef(&self, expr_id
: NodeId
, autoderefs
: u32) -> bool
{
2615 self.tables
.borrow().method_map
.contains_key(&MethodCall
::autoderef(expr_id
,
2619 pub fn upvar_capture(&self, upvar_id
: ty
::UpvarId
) -> Option
<ty
::UpvarCapture
> {
2620 Some(self.tables
.borrow().upvar_capture_map
.get(&upvar_id
).unwrap().clone())
2624 pub fn visit_all_items_in_krate
<V
,F
>(&self,
2627 where F
: FnMut(DefId
) -> DepNode
, V
: Visitor
<'tcx
>
2629 dep_graph
::visit_all_items_in_krate(self, dep_node_fn
, visitor
);
2633 /// The category of explicit self.
2634 #[derive(Clone, Copy, Eq, PartialEq, Debug)]
2635 pub enum ExplicitSelfCategory
{
2638 ByReference(Region
, hir
::Mutability
),
2642 /// A free variable referred to in a function.
2643 #[derive(Copy, Clone, RustcEncodable, RustcDecodable)]
2644 pub struct Freevar
{
2645 /// The variable being accessed free.
2648 // First span where it is accessed (there can be multiple).
2652 pub type FreevarMap
= NodeMap
<Vec
<Freevar
>>;
2654 pub type CaptureModeMap
= NodeMap
<hir
::CaptureClause
>;
2656 // Trait method resolution
2657 pub type TraitMap
= NodeMap
<Vec
<DefId
>>;
2659 // Map from the NodeId of a glob import to a list of items which are actually
2661 pub type GlobMap
= HashMap
<NodeId
, HashSet
<Name
>>;
2663 impl<'tcx
> ctxt
<'tcx
> {
2664 pub fn with_freevars
<T
, F
>(&self, fid
: NodeId
, f
: F
) -> T
where
2665 F
: FnOnce(&[Freevar
]) -> T
,
2667 match self.freevars
.borrow().get(&fid
) {
2669 Some(d
) => f(&d
[..])
2673 pub fn make_substs_for_receiver_types(&self,
2674 trait_ref
: &ty
::TraitRef
<'tcx
>,
2675 method
: &ty
::Method
<'tcx
>)
2676 -> subst
::Substs
<'tcx
>
2679 * Substitutes the values for the receiver's type parameters
2680 * that are found in method, leaving the method's type parameters
2684 let meth_tps
: Vec
<Ty
> =
2685 method
.generics
.types
.get_slice(subst
::FnSpace
)
2687 .map(|def
| self.mk_param_from_def(def
))
2689 let meth_regions
: Vec
<ty
::Region
> =
2690 method
.generics
.regions
.get_slice(subst
::FnSpace
)
2692 .map(|def
| def
.to_early_bound_region())
2694 trait_ref
.substs
.clone().with_method(meth_tps
, meth_regions
)