1 // Copyright 2012-2014 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 #![allow(non_camel_case_types)]
14 use driver::session::Session;
16 use metadata::csearch;
17 use middle::const_eval;
19 use middle::dependency_format;
20 use middle::freevars::CaptureModeMap;
22 use middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem};
23 use middle::lang_items::{FnOnceTraitLangItem, OpaqueStructLangItem};
24 use middle::lang_items::{TyDescStructLangItem, TyVisitorTraitLangItem};
25 use middle::mem_categorization as mc;
27 use middle::resolve_lifetime;
28 use middle::stability;
29 use middle::subst::{Subst, Substs, VecPerParamSpace};
34 use middle::ty_fold::{TypeFoldable,TypeFolder};
36 use util::ppaux::{note_and_explain_region, bound_region_ptr_to_string};
37 use util::ppaux::{trait_store_to_string, ty_to_string};
38 use util::ppaux::{Repr, UserString};
39 use util::common::{indenter};
40 use util::nodemap::{NodeMap, NodeSet, DefIdMap, DefIdSet, FnvHashMap};
42 use std::cell::{Cell, RefCell};
46 use std::hash::{Hash, sip, Writer};
48 use std::iter::AdditiveIterator;
52 use std::collections::{HashMap, HashSet};
53 use arena::TypedArena;
55 use syntax::ast::{CrateNum, DefId, FnStyle, Ident, ItemTrait, LOCAL_CRATE};
56 use syntax::ast::{MutImmutable, MutMutable, Name, NamedField, NodeId};
57 use syntax::ast::{Onceness, StmtExpr, StmtSemi, StructField, UnnamedField};
58 use syntax::ast::{Visibility};
59 use syntax::ast_util::{PostExpansionMethod, is_local, lit_is_str};
62 use syntax::attr::AttrMetaMethods;
63 use syntax::codemap::Span;
64 use syntax::parse::token;
65 use syntax::parse::token::InternedString;
66 use syntax::{ast, ast_map};
67 use syntax::util::small_vector::SmallVector;
68 use std::collections::enum_set::{EnumSet, CLike};
72 pub static INITIAL_DISCRIMINANT_VALUE: Disr = 0;
76 #[deriving(PartialEq, Eq, Hash)]
78 pub ident: ast::Ident,
83 pub enum ImplOrTraitItemContainer {
84 TraitContainer(ast::DefId),
85 ImplContainer(ast::DefId),
88 impl ImplOrTraitItemContainer {
89 pub fn id(&self) -> ast::DefId {
91 TraitContainer(id) => id,
92 ImplContainer(id) => id,
98 pub enum ImplOrTraitItem {
99 MethodTraitItem(Rc<Method>),
102 impl ImplOrTraitItem {
103 fn id(&self) -> ImplOrTraitItemId {
105 MethodTraitItem(ref method) => MethodTraitItemId(method.def_id),
109 pub fn def_id(&self) -> ast::DefId {
111 MethodTraitItem(ref method) => method.def_id,
115 pub fn ident(&self) -> ast::Ident {
117 MethodTraitItem(ref method) => method.ident,
121 pub fn container(&self) -> ImplOrTraitItemContainer {
123 MethodTraitItem(ref method) => method.container,
129 pub enum ImplOrTraitItemId {
130 MethodTraitItemId(ast::DefId),
133 impl ImplOrTraitItemId {
134 pub fn def_id(&self) -> ast::DefId {
136 MethodTraitItemId(def_id) => def_id,
143 pub ident: ast::Ident,
144 pub generics: ty::Generics,
146 pub explicit_self: ExplicitSelfCategory,
147 pub vis: ast::Visibility,
148 pub def_id: ast::DefId,
149 pub container: ImplOrTraitItemContainer,
151 // If this method is provided, we need to know where it came from
152 pub provided_source: Option<ast::DefId>
156 pub fn new(ident: ast::Ident,
157 generics: ty::Generics,
159 explicit_self: ExplicitSelfCategory,
160 vis: ast::Visibility,
162 container: ImplOrTraitItemContainer,
163 provided_source: Option<ast::DefId>)
169 explicit_self: explicit_self,
172 container: container,
173 provided_source: provided_source
177 pub fn container_id(&self) -> ast::DefId {
178 match self.container {
179 TraitContainer(id) => id,
180 ImplContainer(id) => id,
185 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
188 pub mutbl: ast::Mutability,
191 #[deriving(Clone, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
192 pub enum TraitStore {
195 /// &Trait and &mut Trait
196 RegionTraitStore(Region, ast::Mutability),
199 #[deriving(Clone, Show)]
200 pub struct field_ty {
203 pub vis: ast::Visibility,
204 pub origin: ast::DefId, // The DefId of the struct in which the field is declared.
207 // Contains information needed to resolve types and (in the future) look up
208 // the types of AST nodes.
209 #[deriving(PartialEq, Eq, Hash)]
210 pub struct creader_cache_key {
216 pub type creader_cache = RefCell<HashMap<creader_cache_key, t>>;
218 pub struct intern_key {
222 // NB: Do not replace this with #[deriving(PartialEq)]. The automatically-derived
223 // implementation will not recurse through sty and you will get stack
225 impl cmp::PartialEq for intern_key {
226 fn eq(&self, other: &intern_key) -> bool {
228 *self.sty == *other.sty
231 fn ne(&self, other: &intern_key) -> bool {
236 impl Eq for intern_key {}
238 impl<W:Writer> Hash<W> for intern_key {
239 fn hash(&self, s: &mut W) {
240 unsafe { (*self.sty).hash(s) }
244 pub enum ast_ty_to_ty_cache_entry {
245 atttce_unresolved, /* not resolved yet */
246 atttce_resolved(t) /* resolved to a type, irrespective of region */
249 #[deriving(Clone, PartialEq, Decodable, Encodable)]
250 pub struct ItemVariances {
251 pub types: VecPerParamSpace<Variance>,
252 pub regions: VecPerParamSpace<Variance>,
255 #[deriving(Clone, PartialEq, Decodable, Encodable, Show)]
257 Covariant, // T<A> <: T<B> iff A <: B -- e.g., function return type
258 Invariant, // T<A> <: T<B> iff B == A -- e.g., type of mutable cell
259 Contravariant, // T<A> <: T<B> iff B <: A -- e.g., function param type
260 Bivariant, // T<A> <: T<B> -- e.g., unused type parameter
264 pub enum AutoAdjustment {
265 AutoAddEnv(ty::TraitStore),
266 AutoDerefRef(AutoDerefRef)
269 #[deriving(Clone, PartialEq)]
270 pub enum UnsizeKind {
271 // [T, ..n] -> [T], the uint field is n.
273 // An unsize coercion applied to the tail field of a struct.
274 // The uint is the index of the type parameter which is unsized.
275 UnsizeStruct(Box<UnsizeKind>, uint),
276 UnsizeVtable(ty::ExistentialBounds,
277 ast::DefId, /* Trait ID */
278 subst::Substs /* Trait substitutions */)
282 pub struct AutoDerefRef {
283 pub autoderefs: uint,
284 pub autoref: Option<AutoRef>
287 #[deriving(Clone, PartialEq)]
289 /// Convert from T to &T
290 /// The third field allows us to wrap other AutoRef adjustments.
291 AutoPtr(Region, ast::Mutability, Option<Box<AutoRef>>),
293 /// Convert [T, ..n] to [T] (or similar, depending on the kind)
294 AutoUnsize(UnsizeKind),
296 /// Convert Box<[T, ..n]> to Box<[T]> or something similar in a Box.
297 /// With DST and Box a library type, this should be replaced by UnsizeStruct.
298 AutoUnsizeUniq(UnsizeKind),
300 /// Convert from T to *T
301 /// Value to thin pointer
302 /// The second field allows us to wrap other AutoRef adjustments.
303 AutoUnsafe(ast::Mutability, Option<Box<AutoRef>>),
306 // Ugly little helper function. The first bool in the returned tuple is true if
307 // there is an 'unsize to trait object' adjustment at the bottom of the
308 // adjustment. If that is surrounded by an AutoPtr, then we also return the
309 // region of the AutoPtr (in the third argument). The second bool is true if the
310 // adjustment is unique.
311 fn autoref_object_region(autoref: &AutoRef) -> (bool, bool, Option<Region>) {
312 fn unsize_kind_is_object(k: &UnsizeKind) -> bool {
314 &UnsizeVtable(..) => true,
315 &UnsizeStruct(box ref k, _) => unsize_kind_is_object(k),
321 &AutoUnsize(ref k) => (unsize_kind_is_object(k), false, None),
322 &AutoUnsizeUniq(ref k) => (unsize_kind_is_object(k), true, None),
323 &AutoPtr(adj_r, _, Some(box ref autoref)) => {
324 let (b, u, r) = autoref_object_region(autoref);
325 if r.is_some() || u {
331 &AutoUnsafe(_, Some(box ref autoref)) => autoref_object_region(autoref),
332 _ => (false, false, None)
336 // If the adjustment introduces a borrowed reference to a trait object, then
337 // returns the region of the borrowed reference.
338 pub fn adjusted_object_region(adj: &AutoAdjustment) -> Option<Region> {
340 &AutoDerefRef(AutoDerefRef{autoref: Some(ref autoref), ..}) => {
341 let (b, _, r) = autoref_object_region(autoref);
352 // Returns true if there is a trait cast at the bottom of the adjustment.
353 pub fn adjust_is_object(adj: &AutoAdjustment) -> bool {
355 &AutoDerefRef(AutoDerefRef{autoref: Some(ref autoref), ..}) => {
356 let (b, _, _) = autoref_object_region(autoref);
363 // If possible, returns the type expected from the given adjustment. This is not
364 // possible if the adjustment depends on the type of the adjusted expression.
365 pub fn type_of_adjust(cx: &ctxt, adj: &AutoAdjustment) -> Option<t> {
366 fn type_of_autoref(cx: &ctxt, autoref: &AutoRef) -> Option<t> {
368 &AutoUnsize(ref k) => match k {
369 &UnsizeVtable(bounds, def_id, ref substs) => {
370 Some(mk_trait(cx, def_id, substs.clone(), bounds))
374 &AutoUnsizeUniq(ref k) => match k {
375 &UnsizeVtable(bounds, def_id, ref substs) => {
376 Some(mk_uniq(cx, mk_trait(cx, def_id, substs.clone(), bounds)))
380 &AutoPtr(r, m, Some(box ref autoref)) => {
381 match type_of_autoref(cx, autoref) {
382 Some(t) => Some(mk_rptr(cx, r, mt {mutbl: m, ty: t})),
386 &AutoUnsafe(m, Some(box ref autoref)) => {
387 match type_of_autoref(cx, autoref) {
388 Some(t) => Some(mk_ptr(cx, mt {mutbl: m, ty: t})),
397 &AutoDerefRef(AutoDerefRef{autoref: Some(ref autoref), ..}) => {
398 type_of_autoref(cx, autoref)
406 /// A restriction that certain types must be the same size. The use of
407 /// `transmute` gives rise to these restrictions.
408 pub struct TransmuteRestriction {
409 /// The span from whence the restriction comes.
411 /// The type being transmuted from.
413 /// The type being transmuted to.
415 /// NodeIf of the transmute intrinsic.
419 /// The data structure to keep track of all the information that typechecker
420 /// generates so that so that it can be reused and doesn't have to be redone
422 pub struct ctxt<'tcx> {
423 /// The arena that types are allocated from.
424 type_arena: &'tcx TypedArena<t_box_>,
426 /// Specifically use a speedy hash algorithm for this hash map, it's used
428 interner: RefCell<FnvHashMap<intern_key, &'tcx t_box_>>,
429 pub next_id: Cell<uint>,
431 pub def_map: resolve::DefMap,
433 pub named_region_map: resolve_lifetime::NamedRegionMap,
435 pub region_maps: middle::region::RegionMaps,
437 /// Stores the types for various nodes in the AST. Note that this table
438 /// is not guaranteed to be populated until after typeck. See
439 /// typeck::check::fn_ctxt for details.
440 pub node_types: node_type_table,
442 /// Stores the type parameters which were substituted to obtain the type
443 /// of this node. This only applies to nodes that refer to entities
444 /// parameterized by type parameters, such as generic fns, types, or
446 pub item_substs: RefCell<NodeMap<ItemSubsts>>,
448 /// Maps from a trait item to the trait item "descriptor"
449 pub impl_or_trait_items: RefCell<DefIdMap<ImplOrTraitItem>>,
451 /// Maps from a trait def-id to a list of the def-ids of its trait items
452 pub trait_item_def_ids: RefCell<DefIdMap<Rc<Vec<ImplOrTraitItemId>>>>,
454 /// A cache for the trait_items() routine
455 pub trait_items_cache: RefCell<DefIdMap<Rc<Vec<ImplOrTraitItem>>>>,
457 pub impl_trait_cache: RefCell<DefIdMap<Option<Rc<ty::TraitRef>>>>,
459 pub trait_refs: RefCell<NodeMap<Rc<TraitRef>>>,
460 pub trait_defs: RefCell<DefIdMap<Rc<TraitDef>>>,
462 pub map: ast_map::Map,
463 pub intrinsic_defs: RefCell<DefIdMap<t>>,
464 pub freevars: RefCell<freevars::freevar_map>,
465 pub tcache: type_cache,
466 pub rcache: creader_cache,
467 pub short_names_cache: RefCell<HashMap<t, String>>,
468 pub needs_unwind_cleanup_cache: RefCell<HashMap<t, bool>>,
469 pub tc_cache: RefCell<HashMap<uint, TypeContents>>,
470 pub ast_ty_to_ty_cache: RefCell<NodeMap<ast_ty_to_ty_cache_entry>>,
471 pub enum_var_cache: RefCell<DefIdMap<Rc<Vec<Rc<VariantInfo>>>>>,
472 pub ty_param_defs: RefCell<NodeMap<TypeParameterDef>>,
473 pub adjustments: RefCell<NodeMap<AutoAdjustment>>,
474 pub normalized_cache: RefCell<HashMap<t, t>>,
475 pub lang_items: middle::lang_items::LanguageItems,
476 /// A mapping of fake provided method def_ids to the default implementation
477 pub provided_method_sources: RefCell<DefIdMap<ast::DefId>>,
478 pub superstructs: RefCell<DefIdMap<Option<ast::DefId>>>,
479 pub struct_fields: RefCell<DefIdMap<Rc<Vec<field_ty>>>>,
481 /// Maps from def-id of a type or region parameter to its
482 /// (inferred) variance.
483 pub item_variance_map: RefCell<DefIdMap<Rc<ItemVariances>>>,
485 /// True if the variance has been computed yet; false otherwise.
486 pub variance_computed: Cell<bool>,
488 /// A mapping from the def ID of an enum or struct type to the def ID
489 /// of the method that implements its destructor. If the type is not
490 /// present in this map, it does not have a destructor. This map is
491 /// populated during the coherence phase of typechecking.
492 pub destructor_for_type: RefCell<DefIdMap<ast::DefId>>,
494 /// A method will be in this list if and only if it is a destructor.
495 pub destructors: RefCell<DefIdSet>,
497 /// Maps a trait onto a list of impls of that trait.
498 pub trait_impls: RefCell<DefIdMap<Rc<RefCell<Vec<ast::DefId>>>>>,
500 /// Maps a DefId of a type to a list of its inherent impls.
501 /// Contains implementations of methods that are inherent to a type.
502 /// Methods in these implementations don't need to be exported.
503 pub inherent_impls: RefCell<DefIdMap<Rc<RefCell<Vec<ast::DefId>>>>>,
505 /// Maps a DefId of an impl to a list of its items.
506 /// Note that this contains all of the impls that we know about,
507 /// including ones in other crates. It's not clear that this is the best
509 pub impl_items: RefCell<DefIdMap<Vec<ImplOrTraitItemId>>>,
511 /// Set of used unsafe nodes (functions or blocks). Unsafe nodes not
512 /// present in this set can be warned about.
513 pub used_unsafe: RefCell<NodeSet>,
515 /// Set of nodes which mark locals as mutable which end up getting used at
516 /// some point. Local variable definitions not in this set can be warned
518 pub used_mut_nodes: RefCell<NodeSet>,
520 /// vtable resolution information for impl declarations
521 pub impl_vtables: typeck::impl_vtable_map,
523 /// The set of external nominal types whose implementations have been read.
524 /// This is used for lazy resolution of methods.
525 pub populated_external_types: RefCell<DefIdSet>,
527 /// The set of external traits whose implementations have been read. This
528 /// is used for lazy resolution of traits.
529 pub populated_external_traits: RefCell<DefIdSet>,
532 pub upvar_borrow_map: RefCell<UpvarBorrowMap>,
534 /// These two caches are used by const_eval when decoding external statics
535 /// and variants that are found.
536 pub extern_const_statics: RefCell<DefIdMap<Option<Gc<ast::Expr>>>>,
537 pub extern_const_variants: RefCell<DefIdMap<Option<Gc<ast::Expr>>>>,
539 pub method_map: typeck::MethodMap,
540 pub vtable_map: typeck::vtable_map,
542 pub dependency_formats: RefCell<dependency_format::Dependencies>,
544 /// Records the type of each unboxed closure. The def ID is the ID of the
545 /// expression defining the unboxed closure.
546 pub unboxed_closures: RefCell<DefIdMap<UnboxedClosure>>,
548 pub node_lint_levels: RefCell<HashMap<(ast::NodeId, lint::LintId),
551 /// The types that must be asserted to be the same size for `transmute`
552 /// to be valid. We gather up these restrictions in the intrinsicck pass
553 /// and check them in trans.
554 pub transmute_restrictions: RefCell<Vec<TransmuteRestriction>>,
556 /// Maps any item's def-id to its stability index.
557 pub stability: RefCell<stability::Index>,
559 /// Maps closures to their capture clauses.
560 pub capture_modes: RefCell<CaptureModeMap>,
571 // a meta-pub flag: subst may be required if the type has parameters, a self
572 // type, or references bound regions
573 needs_subst = 1 | 2 | 8
576 pub type t_box = &'static t_box_;
585 // To reduce refcounting cost, we're representing types as unsafe pointers
586 // throughout the compiler. These are simply casted t_box values. Use ty::get
587 // to cast them back to a box. (Without the cast, compiler performance suffers
588 // ~15%.) This does mean that a t value relies on the ctxt to keep its box
589 // alive, and using ty::get is unsafe when the ctxt is no longer alive.
592 #[allow(raw_pointer_deriving)]
593 #[deriving(Clone, PartialEq, Eq, Hash)]
594 pub struct t { inner: *const t_opaque }
596 impl fmt::Show for t {
597 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
598 write!(f, "{}", get(*self))
602 pub fn get(t: t) -> t_box {
604 let t2: t_box = mem::transmute(t);
609 pub fn tbox_has_flag(tb: t_box, flag: tbox_flag) -> bool {
610 (tb.flags & (flag as uint)) != 0u
612 pub fn type_has_params(t: t) -> bool {
613 tbox_has_flag(get(t), has_params)
615 pub fn type_has_self(t: t) -> bool { tbox_has_flag(get(t), has_self) }
616 pub fn type_needs_infer(t: t) -> bool {
617 tbox_has_flag(get(t), needs_infer)
619 pub fn type_id(t: t) -> uint { get(t).id }
621 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
622 pub struct BareFnTy {
623 pub fn_style: ast::FnStyle,
628 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
629 pub struct ClosureTy {
630 pub fn_style: ast::FnStyle,
631 pub onceness: ast::Onceness,
632 pub store: TraitStore,
633 pub bounds: ExistentialBounds,
639 * Signature of a function type, which I have arbitrarily
640 * decided to use to refer to the input/output types.
642 * - `binder_id` is the node id where this fn type appeared;
643 * it is used to identify all the bound regions appearing
644 * in the input/output types that are bound by this fn type
645 * (vs some enclosing or enclosed fn type)
646 * - `inputs` is the list of arguments and their modes.
647 * - `output` is the return type.
648 * - `variadic` indicates whether this is a varidic function. (only true for foreign fns)
650 #[deriving(Clone, PartialEq, Eq, Hash)]
652 pub binder_id: ast::NodeId,
658 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
660 pub space: subst::ParamSpace,
665 /// Representation of regions:
666 #[deriving(Clone, PartialEq, Eq, Hash, Encodable, Decodable, Show)]
668 // Region bound in a type or fn declaration which will be
669 // substituted 'early' -- that is, at the same time when type
670 // parameters are substituted.
671 ReEarlyBound(/* param id */ ast::NodeId,
676 // Region bound in a function scope, which will be substituted when the
677 // function is called. The first argument must be the `binder_id` of
678 // some enclosing function signature.
679 ReLateBound(/* binder_id */ ast::NodeId, BoundRegion),
681 /// When checking a function body, the types of all arguments and so forth
682 /// that refer to bound region parameters are modified to refer to free
683 /// region parameters.
686 /// A concrete region naming some expression within the current function.
689 /// Static data that has an "infinite" lifetime. Top in the region lattice.
692 /// A region variable. Should not exist after typeck.
693 ReInfer(InferRegion),
695 /// Empty lifetime is for data that is never accessed.
696 /// Bottom in the region lattice. We treat ReEmpty somewhat
697 /// specially; at least right now, we do not generate instances of
698 /// it during the GLB computations, but rather
699 /// generate an error instead. This is to improve error messages.
700 /// The only way to get an instance of ReEmpty is to have a region
701 /// variable with no constraints.
706 * Upvars do not get their own node-id. Instead, we use the pair of
707 * the original var id (that is, the root variable that is referenced
708 * by the upvar) and the id of the closure expression.
710 #[deriving(Clone, PartialEq, Eq, Hash)]
712 pub var_id: ast::NodeId,
713 pub closure_expr_id: ast::NodeId,
716 #[deriving(Clone, PartialEq, Eq, Hash, Show, Encodable, Decodable)]
717 pub enum BorrowKind {
718 /// Data must be immutable and is aliasable.
721 /// Data must be immutable but not aliasable. This kind of borrow
722 /// cannot currently be expressed by the user and is used only in
723 /// implicit closure bindings. It is needed when you the closure
724 /// is borrowing or mutating a mutable referent, e.g.:
726 /// let x: &mut int = ...;
727 /// let y = || *x += 5;
729 /// If we were to try to translate this closure into a more explicit
730 /// form, we'd encounter an error with the code as written:
732 /// struct Env { x: & &mut int }
733 /// let x: &mut int = ...;
734 /// let y = (&mut Env { &x }, fn_ptr); // Closure is pair of env and fn
735 /// fn fn_ptr(env: &mut Env) { **env.x += 5; }
737 /// This is then illegal because you cannot mutate a `&mut` found
738 /// in an aliasable location. To solve, you'd have to translate with
739 /// an `&mut` borrow:
741 /// struct Env { x: & &mut int }
742 /// let x: &mut int = ...;
743 /// let y = (&mut Env { &mut x }, fn_ptr); // changed from &x to &mut x
744 /// fn fn_ptr(env: &mut Env) { **env.x += 5; }
746 /// Now the assignment to `**env.x` is legal, but creating a
747 /// mutable pointer to `x` is not because `x` is not mutable. We
748 /// could fix this by declaring `x` as `let mut x`. This is ok in
749 /// user code, if awkward, but extra weird for closures, since the
750 /// borrow is hidden.
752 /// So we introduce a "unique imm" borrow -- the referent is
753 /// immutable, but not aliasable. This solves the problem. For
754 /// simplicity, we don't give users the way to express this
755 /// borrow, it's just used when translating closures.
758 /// Data is mutable and not aliasable.
763 * Information describing the borrowing of an upvar. This is computed
764 * during `typeck`, specifically by `regionck`. The general idea is
765 * that the compiler analyses treat closures like:
767 * let closure: &'e fn() = || {
768 * x = 1; // upvar x is assigned to
769 * use(y); // upvar y is read
770 * foo(&z); // upvar z is borrowed immutably
773 * as if they were "desugared" to something loosely like:
775 * struct Vars<'x,'y,'z> { x: &'x mut int,
778 * let closure: &'e fn() = {
784 * let env: &'e mut Vars<'x,'y,'z> = &mut Vars { x: &'x mut x,
790 * This is basically what happens at runtime. The closure is basically
791 * an existentially quantified version of the `(env, f)` pair.
793 * This data structure indicates the region and mutability of a single
794 * one of the `x...z` borrows.
796 * It may not be obvious why each borrowed variable gets its own
797 * lifetime (in the desugared version of the example, these are indicated
798 * by the lifetime parameters `'x`, `'y`, and `'z` in the `Vars` definition).
799 * Each such lifetime must encompass the lifetime `'e` of the closure itself,
800 * but need not be identical to it. The reason that this makes sense:
802 * - Callers are only permitted to invoke the closure, and hence to
803 * use the pointers, within the lifetime `'e`, so clearly `'e` must
804 * be a sublifetime of `'x...'z`.
805 * - The closure creator knows which upvars were borrowed by the closure
806 * and thus `x...z` will be reserved for `'x...'z` respectively.
807 * - Through mutation, the borrowed upvars can actually escape
808 * the closure, so sometimes it is necessary for them to be larger
809 * than the closure lifetime itself.
811 #[deriving(PartialEq, Clone, Encodable, Decodable)]
812 pub struct UpvarBorrow {
813 pub kind: BorrowKind,
814 pub region: ty::Region,
817 pub type UpvarBorrowMap = HashMap<UpvarId, UpvarBorrow>;
820 pub fn is_bound(&self) -> bool {
822 &ty::ReEarlyBound(..) => true,
823 &ty::ReLateBound(..) => true,
829 #[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, Encodable, Decodable, Show)]
830 pub struct FreeRegion {
831 pub scope_id: NodeId,
832 pub bound_region: BoundRegion
835 #[deriving(Clone, PartialEq, PartialOrd, Eq, Ord, Hash, Encodable, Decodable, Show)]
836 pub enum BoundRegion {
837 /// An anonymous region parameter for a given fn (&T)
840 /// Named region parameters for functions (a in &'a T)
842 /// The def-id is needed to distinguish free regions in
843 /// the event of shadowing.
844 BrNamed(ast::DefId, ast::Name),
846 /// Fresh bound identifiers created during GLB computations.
855 macro_rules! def_prim_ty(
856 ($name:ident, $sty:expr, $id:expr) => (
857 pub static $name: t_box_ = t_box_ {
865 def_prim_ty!(TY_NIL, super::ty_nil, 0)
866 def_prim_ty!(TY_BOOL, super::ty_bool, 1)
867 def_prim_ty!(TY_CHAR, super::ty_char, 2)
868 def_prim_ty!(TY_INT, super::ty_int(ast::TyI), 3)
869 def_prim_ty!(TY_I8, super::ty_int(ast::TyI8), 4)
870 def_prim_ty!(TY_I16, super::ty_int(ast::TyI16), 5)
871 def_prim_ty!(TY_I32, super::ty_int(ast::TyI32), 6)
872 def_prim_ty!(TY_I64, super::ty_int(ast::TyI64), 7)
873 def_prim_ty!(TY_UINT, super::ty_uint(ast::TyU), 8)
874 def_prim_ty!(TY_U8, super::ty_uint(ast::TyU8), 9)
875 def_prim_ty!(TY_U16, super::ty_uint(ast::TyU16), 10)
876 def_prim_ty!(TY_U32, super::ty_uint(ast::TyU32), 11)
877 def_prim_ty!(TY_U64, super::ty_uint(ast::TyU64), 12)
878 def_prim_ty!(TY_F32, super::ty_float(ast::TyF32), 14)
879 def_prim_ty!(TY_F64, super::ty_float(ast::TyF64), 15)
881 pub static TY_BOT: t_box_ = t_box_ {
884 flags: super::has_ty_bot as uint,
887 pub static TY_ERR: t_box_ = t_box_ {
890 flags: super::has_ty_err as uint,
893 pub static LAST_PRIMITIVE_ID: uint = 18;
896 // NB: If you change this, you'll probably want to change the corresponding
897 // AST structure in libsyntax/ast.rs as well.
898 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
905 ty_uint(ast::UintTy),
906 ty_float(ast::FloatTy),
907 /// Substs here, possibly against intuition, *may* contain `ty_param`s.
908 /// That is, even after substitution it is possible that there are type
909 /// variables. This happens when the `ty_enum` corresponds to an enum
910 /// definition and not a concrete use of it. To get the correct `ty_enum`
911 /// from the tcx, use the `NodeId` from the `ast::Ty` and look it up in
912 /// the `ast_ty_to_ty_cache`. This is probably true for `ty_struct` as
914 ty_enum(DefId, Substs),
918 ty_vec(t, Option<uint>), // Second field is length.
921 ty_bare_fn(BareFnTy),
922 ty_closure(Box<ClosureTy>),
923 ty_trait(Box<TyTrait>),
924 ty_struct(DefId, Substs),
925 ty_unboxed_closure(DefId, Region),
928 ty_param(ParamTy), // type parameter
929 ty_open(t), // A deref'ed fat pointer, i.e., a dynamically sized value
930 // and its size. Only ever used in trans. It is not necessary
931 // earlier since we don't need to distinguish a DST with its
932 // size (e.g., in a deref) vs a DST with the size elsewhere (
933 // e.g., in a field).
935 ty_infer(InferTy), // something used only during inference/typeck
936 ty_err, // Also only used during inference/typeck, to represent
937 // the type of an erroneous expression (helps cut down
938 // on non-useful type error messages)
941 #[deriving(Clone, PartialEq, Eq, Hash, Show)]
945 pub bounds: ExistentialBounds
948 #[deriving(PartialEq, Eq, Hash, Show)]
949 pub struct TraitRef {
954 #[deriving(Clone, PartialEq)]
955 pub enum IntVarValue {
957 UintType(ast::UintTy),
960 #[deriving(Clone, Show)]
961 pub enum terr_vstore_kind {
968 #[deriving(Clone, Show)]
969 pub struct expected_found<T> {
974 // Data structures used in type unification
975 #[deriving(Clone, Show)]
978 terr_fn_style_mismatch(expected_found<FnStyle>),
979 terr_onceness_mismatch(expected_found<Onceness>),
980 terr_abi_mismatch(expected_found<abi::Abi>),
982 terr_sigil_mismatch(expected_found<TraitStore>),
987 terr_tuple_size(expected_found<uint>),
988 terr_ty_param_size(expected_found<uint>),
989 terr_record_size(expected_found<uint>),
990 terr_record_mutability,
991 terr_record_fields(expected_found<Ident>),
993 terr_regions_does_not_outlive(Region, Region),
994 terr_regions_not_same(Region, Region),
995 terr_regions_no_overlap(Region, Region),
996 terr_regions_insufficiently_polymorphic(BoundRegion, Region),
997 terr_regions_overly_polymorphic(BoundRegion, Region),
998 terr_trait_stores_differ(terr_vstore_kind, expected_found<TraitStore>),
999 terr_sorts(expected_found<t>),
1000 terr_integer_as_char,
1001 terr_int_mismatch(expected_found<IntVarValue>),
1002 terr_float_mismatch(expected_found<ast::FloatTy>),
1003 terr_traits(expected_found<ast::DefId>),
1004 terr_builtin_bounds(expected_found<BuiltinBounds>),
1005 terr_variadic_mismatch(expected_found<bool>),
1009 /// Bounds suitable for a named type parameter like `A` in `fn foo<A>`
1010 /// as well as the existential type parameter in an object type.
1011 #[deriving(PartialEq, Eq, Hash, Clone, Show)]
1012 pub struct ParamBounds {
1013 pub opt_region_bound: Option<ty::Region>,
1014 pub builtin_bounds: BuiltinBounds,
1015 pub trait_bounds: Vec<Rc<TraitRef>>
1018 /// Bounds suitable for an existentially quantified type parameter
1019 /// such as those that appear in object types or closure types. The
1020 /// major difference between this case and `ParamBounds` is that
1021 /// general purpose trait bounds are omitted.
1022 #[deriving(PartialEq, Eq, Hash, Clone, Show)]
1023 pub struct ExistentialBounds {
1024 pub region_bound: ty::Region,
1025 pub builtin_bounds: BuiltinBounds
1028 pub type BuiltinBounds = EnumSet<BuiltinBound>;
1030 #[deriving(Clone, Encodable, PartialEq, Eq, Decodable, Hash, Show)]
1032 pub enum BuiltinBound {
1039 pub fn empty_builtin_bounds() -> BuiltinBounds {
1043 pub fn all_builtin_bounds() -> BuiltinBounds {
1044 let mut set = EnumSet::empty();
1046 set.add(BoundSized);
1051 pub fn region_existential_bound(r: ty::Region) -> ExistentialBounds {
1053 * An existential bound that does not implement any traits.
1056 ty::ExistentialBounds { region_bound: r,
1057 builtin_bounds: empty_builtin_bounds() }
1060 impl CLike for BuiltinBound {
1061 fn to_uint(&self) -> uint {
1064 fn from_uint(v: uint) -> BuiltinBound {
1065 unsafe { mem::transmute(v) }
1069 #[deriving(Clone, PartialEq, Eq, Hash)]
1074 #[deriving(Clone, PartialEq, Eq, Hash)]
1079 #[deriving(Clone, PartialEq, Eq, Hash)]
1080 pub struct FloatVid {
1084 #[deriving(Clone, PartialEq, Eq, Encodable, Decodable, Hash)]
1085 pub struct RegionVid {
1089 #[deriving(Clone, PartialEq, Eq, Hash)]
1096 #[deriving(Clone, Encodable, Decodable, Eq, Hash, Show)]
1097 pub enum InferRegion {
1099 ReSkolemized(uint, BoundRegion)
1102 impl cmp::PartialEq for InferRegion {
1103 fn eq(&self, other: &InferRegion) -> bool {
1104 match ((*self), *other) {
1105 (ReVar(rva), ReVar(rvb)) => {
1108 (ReSkolemized(rva, _), ReSkolemized(rvb, _)) => {
1114 fn ne(&self, other: &InferRegion) -> bool {
1115 !((*self) == (*other))
1119 impl fmt::Show for TyVid {
1120 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result{
1121 write!(f, "<generic #{}>", self.index)
1125 impl fmt::Show for IntVid {
1126 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1127 write!(f, "<generic integer #{}>", self.index)
1131 impl fmt::Show for FloatVid {
1132 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1133 write!(f, "<generic float #{}>", self.index)
1137 impl fmt::Show for RegionVid {
1138 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1139 write!(f, "'<generic lifetime #{}>", self.index)
1143 impl fmt::Show for FnSig {
1144 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1145 // grr, without tcx not much we can do.
1150 impl fmt::Show for InferTy {
1151 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1153 TyVar(ref v) => v.fmt(f),
1154 IntVar(ref v) => v.fmt(f),
1155 FloatVar(ref v) => v.fmt(f),
1160 impl fmt::Show for IntVarValue {
1161 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1163 IntType(ref v) => v.fmt(f),
1164 UintType(ref v) => v.fmt(f),
1169 #[deriving(Clone, Show)]
1170 pub struct TypeParameterDef {
1171 pub ident: ast::Ident,
1172 pub def_id: ast::DefId,
1173 pub space: subst::ParamSpace,
1175 pub bounds: ParamBounds,
1176 pub default: Option<ty::t>,
1179 #[deriving(Encodable, Decodable, Clone, Show)]
1180 pub struct RegionParameterDef {
1181 pub name: ast::Name,
1182 pub def_id: ast::DefId,
1183 pub space: subst::ParamSpace,
1185 pub bounds: Vec<ty::Region>,
1188 /// Information about the type/lifetime parameters associated with an
1189 /// item or method. Analogous to ast::Generics.
1190 #[deriving(Clone, Show)]
1191 pub struct Generics {
1192 pub types: VecPerParamSpace<TypeParameterDef>,
1193 pub regions: VecPerParamSpace<RegionParameterDef>,
1197 pub fn empty() -> Generics {
1198 Generics { types: VecPerParamSpace::empty(),
1199 regions: VecPerParamSpace::empty() }
1202 pub fn has_type_params(&self, space: subst::ParamSpace) -> bool {
1203 !self.types.is_empty_in(space)
1206 pub fn has_region_params(&self, space: subst::ParamSpace) -> bool {
1207 !self.regions.is_empty_in(space)
1211 /// When type checking, we use the `ParameterEnvironment` to track
1212 /// details about the type/lifetime parameters that are in scope.
1213 /// It primarily stores the bounds information.
1215 /// Note: This information might seem to be redundant with the data in
1216 /// `tcx.ty_param_defs`, but it is not. That table contains the
1217 /// parameter definitions from an "outside" perspective, but this
1218 /// struct will contain the bounds for a parameter as seen from inside
1219 /// the function body. Currently the only real distinction is that
1220 /// bound lifetime parameters are replaced with free ones, but in the
1221 /// future I hope to refine the representation of types so as to make
1222 /// more distinctions clearer.
1223 pub struct ParameterEnvironment {
1224 /// A substitution that can be applied to move from
1225 /// the "outer" view of a type or method to the "inner" view.
1226 /// In general, this means converting from bound parameters to
1227 /// free parameters. Since we currently represent bound/free type
1228 /// parameters in the same way, this only has an affect on regions.
1229 pub free_substs: Substs,
1231 /// Bounds on the various type parameters
1232 pub bounds: VecPerParamSpace<ParamBounds>,
1234 /// Each type parameter has an implicit region bound that
1235 /// indicates it must outlive at least the function body (the user
1236 /// may specify stronger requirements). This field indicates the
1237 /// region of the callee.
1238 pub implicit_region_bound: ty::Region,
1241 impl ParameterEnvironment {
1242 pub fn for_item(cx: &ctxt, id: NodeId) -> ParameterEnvironment {
1243 match cx.map.find(id) {
1244 Some(ast_map::NodeImplItem(ref impl_item)) => {
1246 ast::MethodImplItem(ref method) => {
1247 let method_def_id = ast_util::local_def(id);
1248 match ty::impl_or_trait_item(cx, method_def_id) {
1249 MethodTraitItem(ref method_ty) => {
1250 let method_generics = &method_ty.generics;
1251 construct_parameter_environment(
1254 method.pe_body().id)
1260 Some(ast_map::NodeTraitItem(trait_method)) => {
1261 match *trait_method {
1262 ast::RequiredMethod(ref required) => {
1263 cx.sess.span_bug(required.span,
1264 "ParameterEnvironment::from_item():
1265 can't create a parameter \
1266 environment for required trait \
1269 ast::ProvidedMethod(ref method) => {
1270 let method_def_id = ast_util::local_def(id);
1271 match ty::impl_or_trait_item(cx, method_def_id) {
1272 MethodTraitItem(ref method_ty) => {
1273 let method_generics = &method_ty.generics;
1274 construct_parameter_environment(
1277 method.pe_body().id)
1283 Some(ast_map::NodeItem(item)) => {
1285 ast::ItemFn(_, _, _, _, ref body) => {
1286 // We assume this is a function.
1287 let fn_def_id = ast_util::local_def(id);
1288 let fn_pty = ty::lookup_item_type(cx, fn_def_id);
1290 construct_parameter_environment(cx,
1295 ast::ItemStruct(..) |
1297 ast::ItemStatic(..) => {
1298 let def_id = ast_util::local_def(id);
1299 let pty = ty::lookup_item_type(cx, def_id);
1300 construct_parameter_environment(cx, &pty.generics, id)
1303 cx.sess.span_bug(item.span,
1304 "ParameterEnvironment::from_item():
1305 can't create a parameter \
1306 environment for this kind of item")
1311 cx.sess.bug(format!("ParameterEnvironment::from_item(): \
1312 `{}` is not an item",
1313 cx.map.node_to_string(id)).as_slice())
1321 /// - `generics`: the set of type parameters and their bounds
1322 /// - `ty`: the base types, which may reference the parameters defined
1324 #[deriving(Clone, Show)]
1325 pub struct Polytype {
1326 pub generics: Generics,
1330 /// As `Polytype` but for a trait ref.
1331 pub struct TraitDef {
1332 pub generics: Generics,
1333 pub bounds: ParamBounds,
1334 pub trait_ref: Rc<ty::TraitRef>,
1337 /// Records the substitutions used to translate the polytype for an
1338 /// item into the monotype of an item reference.
1340 pub struct ItemSubsts {
1344 pub type type_cache = RefCell<DefIdMap<Polytype>>;
1346 pub type node_type_table = RefCell<HashMap<uint,t>>;
1348 /// Records information about each unboxed closure.
1349 pub struct UnboxedClosure {
1350 /// The type of the unboxed closure.
1351 pub closure_type: ClosureTy,
1352 /// The kind of unboxed closure this is.
1353 pub kind: UnboxedClosureKind,
1356 #[deriving(PartialEq, Eq)]
1357 pub enum UnboxedClosureKind {
1358 FnUnboxedClosureKind,
1359 FnMutUnboxedClosureKind,
1360 FnOnceUnboxedClosureKind,
1363 impl UnboxedClosureKind {
1364 pub fn trait_did(&self, cx: &ctxt) -> ast::DefId {
1365 let result = match *self {
1366 FnUnboxedClosureKind => cx.lang_items.require(FnTraitLangItem),
1367 FnMutUnboxedClosureKind => {
1368 cx.lang_items.require(FnMutTraitLangItem)
1370 FnOnceUnboxedClosureKind => {
1371 cx.lang_items.require(FnOnceTraitLangItem)
1375 Ok(trait_did) => trait_did,
1376 Err(err) => cx.sess.fatal(err.as_slice()),
1381 pub fn mk_ctxt<'tcx>(s: Session,
1382 type_arena: &'tcx TypedArena<t_box_>,
1383 dm: resolve::DefMap,
1384 named_region_map: resolve_lifetime::NamedRegionMap,
1386 freevars: freevars::freevar_map,
1387 capture_modes: freevars::CaptureModeMap,
1388 region_maps: middle::region::RegionMaps,
1389 lang_items: middle::lang_items::LanguageItems,
1390 stability: stability::Index) -> ctxt<'tcx> {
1392 type_arena: type_arena,
1393 interner: RefCell::new(FnvHashMap::new()),
1394 named_region_map: named_region_map,
1395 item_variance_map: RefCell::new(DefIdMap::new()),
1396 variance_computed: Cell::new(false),
1397 next_id: Cell::new(primitives::LAST_PRIMITIVE_ID),
1400 region_maps: region_maps,
1401 node_types: RefCell::new(HashMap::new()),
1402 item_substs: RefCell::new(NodeMap::new()),
1403 trait_refs: RefCell::new(NodeMap::new()),
1404 trait_defs: RefCell::new(DefIdMap::new()),
1406 intrinsic_defs: RefCell::new(DefIdMap::new()),
1407 freevars: RefCell::new(freevars),
1408 tcache: RefCell::new(DefIdMap::new()),
1409 rcache: RefCell::new(HashMap::new()),
1410 short_names_cache: RefCell::new(HashMap::new()),
1411 needs_unwind_cleanup_cache: RefCell::new(HashMap::new()),
1412 tc_cache: RefCell::new(HashMap::new()),
1413 ast_ty_to_ty_cache: RefCell::new(NodeMap::new()),
1414 enum_var_cache: RefCell::new(DefIdMap::new()),
1415 impl_or_trait_items: RefCell::new(DefIdMap::new()),
1416 trait_item_def_ids: RefCell::new(DefIdMap::new()),
1417 trait_items_cache: RefCell::new(DefIdMap::new()),
1418 impl_trait_cache: RefCell::new(DefIdMap::new()),
1419 ty_param_defs: RefCell::new(NodeMap::new()),
1420 adjustments: RefCell::new(NodeMap::new()),
1421 normalized_cache: RefCell::new(HashMap::new()),
1422 lang_items: lang_items,
1423 provided_method_sources: RefCell::new(DefIdMap::new()),
1424 superstructs: RefCell::new(DefIdMap::new()),
1425 struct_fields: RefCell::new(DefIdMap::new()),
1426 destructor_for_type: RefCell::new(DefIdMap::new()),
1427 destructors: RefCell::new(DefIdSet::new()),
1428 trait_impls: RefCell::new(DefIdMap::new()),
1429 inherent_impls: RefCell::new(DefIdMap::new()),
1430 impl_items: RefCell::new(DefIdMap::new()),
1431 used_unsafe: RefCell::new(NodeSet::new()),
1432 used_mut_nodes: RefCell::new(NodeSet::new()),
1433 impl_vtables: RefCell::new(DefIdMap::new()),
1434 populated_external_types: RefCell::new(DefIdSet::new()),
1435 populated_external_traits: RefCell::new(DefIdSet::new()),
1436 upvar_borrow_map: RefCell::new(HashMap::new()),
1437 extern_const_statics: RefCell::new(DefIdMap::new()),
1438 extern_const_variants: RefCell::new(DefIdMap::new()),
1439 method_map: RefCell::new(FnvHashMap::new()),
1440 vtable_map: RefCell::new(FnvHashMap::new()),
1441 dependency_formats: RefCell::new(HashMap::new()),
1442 unboxed_closures: RefCell::new(DefIdMap::new()),
1443 node_lint_levels: RefCell::new(HashMap::new()),
1444 transmute_restrictions: RefCell::new(Vec::new()),
1445 stability: RefCell::new(stability),
1446 capture_modes: RefCell::new(capture_modes),
1450 // Type constructors
1452 // Interns a type/name combination, stores the resulting box in cx.interner,
1453 // and returns the box as cast to an unsafe ptr (see comments for t above).
1454 pub fn mk_t(cx: &ctxt, st: sty) -> t {
1455 // Check for primitive types.
1457 ty_nil => return mk_nil(),
1458 ty_err => return mk_err(),
1459 ty_bool => return mk_bool(),
1460 ty_int(i) => return mk_mach_int(i),
1461 ty_uint(u) => return mk_mach_uint(u),
1462 ty_float(f) => return mk_mach_float(f),
1463 ty_char => return mk_char(),
1464 ty_bot => return mk_bot(),
1468 let key = intern_key { sty: &st };
1470 match cx.interner.borrow().find(&key) {
1471 Some(t) => unsafe { return mem::transmute(&t.sty); },
1476 fn rflags(r: Region) -> uint {
1477 (has_regions as uint) | {
1479 ty::ReInfer(_) => needs_infer as uint,
1484 fn sflags(substs: &Substs) -> uint {
1486 let mut i = substs.types.iter();
1488 f |= get(*tt).flags;
1490 match substs.regions {
1491 subst::ErasedRegions => {}
1492 subst::NonerasedRegions(ref regions) => {
1493 for r in regions.iter() {
1500 fn flags_for_bounds(bounds: &ExistentialBounds) -> uint {
1501 rflags(bounds.region_bound)
1504 &ty_nil | &ty_bool | &ty_char | &ty_int(_) | &ty_float(_) | &ty_uint(_) |
1506 // You might think that we could just return ty_err for
1507 // any type containing ty_err as a component, and get
1508 // rid of the has_ty_err flag -- likewise for ty_bot (with
1509 // the exception of function types that return bot).
1510 // But doing so caused sporadic memory corruption, and
1511 // neither I (tjc) nor nmatsakis could figure out why,
1512 // so we're doing it this way.
1513 &ty_bot => flags |= has_ty_bot as uint,
1514 &ty_err => flags |= has_ty_err as uint,
1515 &ty_param(ref p) => {
1516 if p.space == subst::SelfSpace {
1517 flags |= has_self as uint;
1519 flags |= has_params as uint;
1522 &ty_unboxed_closure(_, ref region) => flags |= rflags(*region),
1523 &ty_infer(_) => flags |= needs_infer as uint,
1524 &ty_enum(_, ref substs) | &ty_struct(_, ref substs) => {
1525 flags |= sflags(substs);
1527 &ty_trait(box ty::TyTrait { ref substs, ref bounds, .. }) => {
1528 flags |= sflags(substs);
1529 flags |= flags_for_bounds(bounds);
1531 &ty_box(tt) | &ty_uniq(tt) | &ty_vec(tt, _) | &ty_open(tt) => {
1532 flags |= get(tt).flags
1535 flags |= get(m.ty).flags;
1537 &ty_rptr(r, ref m) => {
1539 flags |= get(m.ty).flags;
1541 &ty_tup(ref ts) => for tt in ts.iter() { flags |= get(*tt).flags; },
1542 &ty_bare_fn(ref f) => {
1543 for a in f.sig.inputs.iter() { flags |= get(*a).flags; }
1544 flags |= get(f.sig.output).flags;
1545 // T -> _|_ is *not* _|_ !
1546 flags &= !(has_ty_bot as uint);
1548 &ty_closure(ref f) => {
1550 RegionTraitStore(r, _) => {
1555 for a in f.sig.inputs.iter() { flags |= get(*a).flags; }
1556 flags |= get(f.sig.output).flags;
1557 // T -> _|_ is *not* _|_ !
1558 flags &= !(has_ty_bot as uint);
1559 flags |= flags_for_bounds(&f.bounds);
1563 let t = cx.type_arena.alloc(t_box_ {
1565 id: cx.next_id.get(),
1569 let sty_ptr = &t.sty as *const sty;
1571 let key = intern_key {
1575 cx.interner.borrow_mut().insert(key, t);
1577 cx.next_id.set(cx.next_id.get() + 1);
1580 mem::transmute::<*const sty, t>(sty_ptr)
1585 pub fn mk_prim_t(primitive: &'static t_box_) -> t {
1587 mem::transmute::<&'static t_box_, t>(primitive)
1592 pub fn mk_nil() -> t { mk_prim_t(&primitives::TY_NIL) }
1595 pub fn mk_err() -> t { mk_prim_t(&primitives::TY_ERR) }
1598 pub fn mk_bot() -> t { mk_prim_t(&primitives::TY_BOT) }
1601 pub fn mk_bool() -> t { mk_prim_t(&primitives::TY_BOOL) }
1604 pub fn mk_int() -> t { mk_prim_t(&primitives::TY_INT) }
1607 pub fn mk_i8() -> t { mk_prim_t(&primitives::TY_I8) }
1610 pub fn mk_i16() -> t { mk_prim_t(&primitives::TY_I16) }
1613 pub fn mk_i32() -> t { mk_prim_t(&primitives::TY_I32) }
1616 pub fn mk_i64() -> t { mk_prim_t(&primitives::TY_I64) }
1619 pub fn mk_f32() -> t { mk_prim_t(&primitives::TY_F32) }
1622 pub fn mk_f64() -> t { mk_prim_t(&primitives::TY_F64) }
1625 pub fn mk_uint() -> t { mk_prim_t(&primitives::TY_UINT) }
1628 pub fn mk_u8() -> t { mk_prim_t(&primitives::TY_U8) }
1631 pub fn mk_u16() -> t { mk_prim_t(&primitives::TY_U16) }
1634 pub fn mk_u32() -> t { mk_prim_t(&primitives::TY_U32) }
1637 pub fn mk_u64() -> t { mk_prim_t(&primitives::TY_U64) }
1639 pub fn mk_mach_int(tm: ast::IntTy) -> t {
1641 ast::TyI => mk_int(),
1642 ast::TyI8 => mk_i8(),
1643 ast::TyI16 => mk_i16(),
1644 ast::TyI32 => mk_i32(),
1645 ast::TyI64 => mk_i64(),
1649 pub fn mk_mach_uint(tm: ast::UintTy) -> t {
1651 ast::TyU => mk_uint(),
1652 ast::TyU8 => mk_u8(),
1653 ast::TyU16 => mk_u16(),
1654 ast::TyU32 => mk_u32(),
1655 ast::TyU64 => mk_u64(),
1659 pub fn mk_mach_float(tm: ast::FloatTy) -> t {
1661 ast::TyF32 => mk_f32(),
1662 ast::TyF64 => mk_f64(),
1667 pub fn mk_char() -> t { mk_prim_t(&primitives::TY_CHAR) }
1669 pub fn mk_str(cx: &ctxt) -> t {
1673 pub fn mk_str_slice(cx: &ctxt, r: Region, m: ast::Mutability) -> t {
1676 ty: mk_t(cx, ty_str),
1681 pub fn mk_enum(cx: &ctxt, did: ast::DefId, substs: Substs) -> t {
1682 // take a copy of substs so that we own the vectors inside
1683 mk_t(cx, ty_enum(did, substs))
1686 pub fn mk_box(cx: &ctxt, ty: t) -> t { mk_t(cx, ty_box(ty)) }
1688 pub fn mk_uniq(cx: &ctxt, ty: t) -> t { mk_t(cx, ty_uniq(ty)) }
1690 pub fn mk_ptr(cx: &ctxt, tm: mt) -> t { mk_t(cx, ty_ptr(tm)) }
1692 pub fn mk_rptr(cx: &ctxt, r: Region, tm: mt) -> t { mk_t(cx, ty_rptr(r, tm)) }
1694 pub fn mk_mut_rptr(cx: &ctxt, r: Region, ty: t) -> t {
1695 mk_rptr(cx, r, mt {ty: ty, mutbl: ast::MutMutable})
1697 pub fn mk_imm_rptr(cx: &ctxt, r: Region, ty: t) -> t {
1698 mk_rptr(cx, r, mt {ty: ty, mutbl: ast::MutImmutable})
1701 pub fn mk_mut_ptr(cx: &ctxt, ty: t) -> t {
1702 mk_ptr(cx, mt {ty: ty, mutbl: ast::MutMutable})
1705 pub fn mk_imm_ptr(cx: &ctxt, ty: t) -> t {
1706 mk_ptr(cx, mt {ty: ty, mutbl: ast::MutImmutable})
1709 pub fn mk_nil_ptr(cx: &ctxt) -> t {
1710 mk_ptr(cx, mt {ty: mk_nil(), mutbl: ast::MutImmutable})
1713 pub fn mk_vec(cx: &ctxt, t: t, sz: Option<uint>) -> t {
1714 mk_t(cx, ty_vec(t, sz))
1717 pub fn mk_slice(cx: &ctxt, r: Region, tm: mt) -> t {
1720 ty: mk_vec(cx, tm.ty, None),
1725 pub fn mk_tup(cx: &ctxt, ts: Vec<t>) -> t { mk_t(cx, ty_tup(ts)) }
1727 pub fn mk_closure(cx: &ctxt, fty: ClosureTy) -> t {
1728 mk_t(cx, ty_closure(box fty))
1731 pub fn mk_bare_fn(cx: &ctxt, fty: BareFnTy) -> t {
1732 mk_t(cx, ty_bare_fn(fty))
1735 pub fn mk_ctor_fn(cx: &ctxt,
1736 binder_id: ast::NodeId,
1737 input_tys: &[ty::t],
1738 output: ty::t) -> t {
1739 let input_args = input_tys.iter().map(|t| *t).collect();
1742 fn_style: ast::NormalFn,
1745 binder_id: binder_id,
1754 pub fn mk_trait(cx: &ctxt,
1757 bounds: ExistentialBounds)
1759 // take a copy of substs so that we own the vectors inside
1760 let inner = box TyTrait {
1765 mk_t(cx, ty_trait(inner))
1768 pub fn mk_struct(cx: &ctxt, struct_id: ast::DefId, substs: Substs) -> t {
1769 // take a copy of substs so that we own the vectors inside
1770 mk_t(cx, ty_struct(struct_id, substs))
1773 pub fn mk_unboxed_closure(cx: &ctxt, closure_id: ast::DefId, region: Region)
1775 mk_t(cx, ty_unboxed_closure(closure_id, region))
1778 pub fn mk_var(cx: &ctxt, v: TyVid) -> t { mk_infer(cx, TyVar(v)) }
1780 pub fn mk_int_var(cx: &ctxt, v: IntVid) -> t { mk_infer(cx, IntVar(v)) }
1782 pub fn mk_float_var(cx: &ctxt, v: FloatVid) -> t { mk_infer(cx, FloatVar(v)) }
1784 pub fn mk_infer(cx: &ctxt, it: InferTy) -> t { mk_t(cx, ty_infer(it)) }
1786 pub fn mk_param(cx: &ctxt, space: subst::ParamSpace, n: uint, k: DefId) -> t {
1787 mk_t(cx, ty_param(ParamTy { space: space, idx: n, def_id: k }))
1790 pub fn mk_self_type(cx: &ctxt, did: ast::DefId) -> t {
1791 mk_param(cx, subst::SelfSpace, 0, did)
1794 pub fn mk_param_from_def(cx: &ctxt, def: &TypeParameterDef) -> t {
1795 mk_param(cx, def.space, def.index, def.def_id)
1798 pub fn mk_open(cx: &ctxt, t: t) -> t { mk_t(cx, ty_open(t)) }
1800 pub fn walk_ty(ty: t, f: |t|) {
1801 maybe_walk_ty(ty, |t| { f(t); true });
1804 pub fn maybe_walk_ty(ty: t, f: |t| -> bool) {
1809 ty_nil | ty_bot | ty_bool | ty_char | ty_int(_) | ty_uint(_) | ty_float(_) |
1810 ty_str | ty_infer(_) | ty_param(_) | ty_unboxed_closure(_, _) | ty_err => {}
1811 ty_box(ty) | ty_uniq(ty) | ty_vec(ty, _) | ty_open(ty) => maybe_walk_ty(ty, f),
1812 ty_ptr(ref tm) | ty_rptr(_, ref tm) => {
1813 maybe_walk_ty(tm.ty, f);
1815 ty_enum(_, ref substs) | ty_struct(_, ref substs) |
1816 ty_trait(box TyTrait { ref substs, .. }) => {
1817 for subty in (*substs).types.iter() {
1818 maybe_walk_ty(*subty, |x| f(x));
1821 ty_tup(ref ts) => { for tt in ts.iter() { maybe_walk_ty(*tt, |x| f(x)); } }
1822 ty_bare_fn(ref ft) => {
1823 for a in ft.sig.inputs.iter() { maybe_walk_ty(*a, |x| f(x)); }
1824 maybe_walk_ty(ft.sig.output, f);
1826 ty_closure(ref ft) => {
1827 for a in ft.sig.inputs.iter() { maybe_walk_ty(*a, |x| f(x)); }
1828 maybe_walk_ty(ft.sig.output, f);
1833 // Folds types from the bottom up.
1834 pub fn fold_ty(cx: &ctxt, t0: t, fldop: |t| -> t) -> t {
1835 let mut f = ty_fold::BottomUpFolder {tcx: cx, fldop: fldop};
1839 pub fn walk_regions_and_ty(cx: &ctxt, ty: t, fldr: |r: Region|, fldt: |t: t|)
1841 ty_fold::RegionFolder::general(cx,
1843 |t| { fldt(t); t }).fold_ty(ty)
1847 pub fn new(space: subst::ParamSpace,
1851 ParamTy { space: space, idx: index, def_id: def_id }
1854 pub fn for_self(trait_def_id: ast::DefId) -> ParamTy {
1855 ParamTy::new(subst::SelfSpace, 0, trait_def_id)
1858 pub fn for_def(def: &TypeParameterDef) -> ParamTy {
1859 ParamTy::new(def.space, def.index, def.def_id)
1862 pub fn to_ty(self, tcx: &ty::ctxt) -> ty::t {
1863 ty::mk_param(tcx, self.space, self.idx, self.def_id)
1868 pub fn empty() -> ItemSubsts {
1869 ItemSubsts { substs: Substs::empty() }
1872 pub fn is_noop(&self) -> bool {
1873 self.substs.is_noop()
1879 pub fn type_is_nil(ty: t) -> bool { get(ty).sty == ty_nil }
1881 pub fn type_is_bot(ty: t) -> bool {
1882 (get(ty).flags & (has_ty_bot as uint)) != 0
1885 pub fn type_is_error(ty: t) -> bool {
1886 (get(ty).flags & (has_ty_err as uint)) != 0
1889 pub fn type_needs_subst(ty: t) -> bool {
1890 tbox_has_flag(get(ty), needs_subst)
1893 pub fn trait_ref_contains_error(tref: &ty::TraitRef) -> bool {
1894 tref.substs.types.any(|&t| type_is_error(t))
1897 pub fn type_is_ty_var(ty: t) -> bool {
1899 ty_infer(TyVar(_)) => true,
1904 pub fn type_is_bool(ty: t) -> bool { get(ty).sty == ty_bool }
1906 pub fn type_is_self(ty: t) -> bool {
1908 ty_param(ref p) => p.space == subst::SelfSpace,
1913 fn type_is_slice(ty: t) -> bool {
1915 ty_ptr(mt) | ty_rptr(_, mt) => match get(mt.ty).sty {
1916 ty_vec(_, None) | ty_str => true,
1923 pub fn type_is_vec(ty: t) -> bool {
1926 ty_ptr(mt{ty: t, ..}) | ty_rptr(_, mt{ty: t, ..}) |
1927 ty_box(t) | ty_uniq(t) => match get(t).sty {
1928 ty_vec(_, None) => true,
1935 pub fn type_is_structural(ty: t) -> bool {
1937 ty_struct(..) | ty_tup(_) | ty_enum(..) | ty_closure(_) |
1938 ty_vec(_, Some(_)) | ty_unboxed_closure(..) => true,
1939 _ => type_is_slice(ty) | type_is_trait(ty)
1943 pub fn type_is_simd(cx: &ctxt, ty: t) -> bool {
1945 ty_struct(did, _) => lookup_simd(cx, did),
1950 pub fn sequence_element_type(cx: &ctxt, ty: t) -> t {
1952 ty_vec(ty, _) => ty,
1953 ty_str => mk_mach_uint(ast::TyU8),
1954 ty_open(ty) => sequence_element_type(cx, ty),
1955 _ => cx.sess.bug(format!("sequence_element_type called on non-sequence value: {}",
1956 ty_to_string(cx, ty)).as_slice()),
1960 pub fn simd_type(cx: &ctxt, ty: t) -> t {
1962 ty_struct(did, ref substs) => {
1963 let fields = lookup_struct_fields(cx, did);
1964 lookup_field_type(cx, did, fields.get(0).id, substs)
1966 _ => fail!("simd_type called on invalid type")
1970 pub fn simd_size(cx: &ctxt, ty: t) -> uint {
1972 ty_struct(did, _) => {
1973 let fields = lookup_struct_fields(cx, did);
1976 _ => fail!("simd_size called on invalid type")
1980 pub fn type_is_boxed(ty: t) -> bool {
1987 pub fn type_is_region_ptr(ty: t) -> bool {
1989 ty_rptr(..) => true,
1994 pub fn type_is_unsafe_ptr(ty: t) -> bool {
1996 ty_ptr(_) => return true,
2001 pub fn type_is_unique(ty: t) -> bool {
2003 ty_uniq(_) => match get(ty).sty {
2004 ty_trait(..) => false,
2011 pub fn type_is_fat_ptr(cx: &ctxt, ty: t) -> bool {
2013 ty_ptr(mt{ty, ..}) | ty_rptr(_, mt{ty, ..})
2014 | ty_uniq(ty) if !type_is_sized(cx, ty) => true,
2020 A scalar type is one that denotes an atomic datum, with no sub-components.
2021 (A ty_ptr is scalar because it represents a non-managed pointer, so its
2022 contents are abstract to rustc.)
2024 pub fn type_is_scalar(ty: t) -> bool {
2026 ty_nil | ty_bool | ty_char | ty_int(_) | ty_float(_) | ty_uint(_) |
2027 ty_infer(IntVar(_)) | ty_infer(FloatVar(_)) |
2028 ty_bare_fn(..) | ty_ptr(_) => true,
2033 /// Returns true if this type is a floating point type and false otherwise.
2034 pub fn type_is_floating_point(ty: t) -> bool {
2036 ty_float(_) => true,
2041 pub fn type_needs_drop(cx: &ctxt, ty: t) -> bool {
2042 type_contents(cx, ty).needs_drop(cx)
2045 // Some things don't need cleanups during unwinding because the
2046 // task can free them all at once later. Currently only things
2047 // that only contain scalars and shared boxes can avoid unwind
2049 pub fn type_needs_unwind_cleanup(cx: &ctxt, ty: t) -> bool {
2050 match cx.needs_unwind_cleanup_cache.borrow().find(&ty) {
2051 Some(&result) => return result,
2055 let mut tycache = HashSet::new();
2056 let needs_unwind_cleanup =
2057 type_needs_unwind_cleanup_(cx, ty, &mut tycache, false);
2058 cx.needs_unwind_cleanup_cache.borrow_mut().insert(ty, needs_unwind_cleanup);
2059 return needs_unwind_cleanup;
2062 fn type_needs_unwind_cleanup_(cx: &ctxt, ty: t,
2063 tycache: &mut HashSet<t>,
2064 encountered_box: bool) -> bool {
2066 // Prevent infinite recursion
2067 if !tycache.insert(ty) {
2071 let mut encountered_box = encountered_box;
2072 let mut needs_unwind_cleanup = false;
2073 maybe_walk_ty(ty, |ty| {
2074 let old_encountered_box = encountered_box;
2075 let result = match get(ty).sty {
2077 encountered_box = true;
2080 ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
2081 ty_tup(_) | ty_ptr(_) => {
2084 ty_enum(did, ref substs) => {
2085 for v in (*enum_variants(cx, did)).iter() {
2086 for aty in v.args.iter() {
2087 let t = aty.subst(cx, substs);
2088 needs_unwind_cleanup |=
2089 type_needs_unwind_cleanup_(cx, t, tycache,
2093 !needs_unwind_cleanup
2096 // Once we're inside a box, the annihilator will find
2097 // it and destroy it.
2098 if !encountered_box {
2099 needs_unwind_cleanup = true;
2106 needs_unwind_cleanup = true;
2111 encountered_box = old_encountered_box;
2115 return needs_unwind_cleanup;
2119 * Type contents is how the type checker reasons about kinds.
2120 * They track what kinds of things are found within a type. You can
2121 * think of them as kind of an "anti-kind". They track the kinds of values
2122 * and thinks that are contained in types. Having a larger contents for
2123 * a type tends to rule that type *out* from various kinds. For example,
2124 * a type that contains a reference is not sendable.
2126 * The reason we compute type contents and not kinds is that it is
2127 * easier for me (nmatsakis) to think about what is contained within
2128 * a type than to think about what is *not* contained within a type.
2130 pub struct TypeContents {
2134 macro_rules! def_type_content_sets(
2135 (mod $mname:ident { $($name:ident = $bits:expr),+ }) => {
2136 #[allow(non_snake_case)]
2138 use middle::ty::TypeContents;
2139 $(pub static $name: TypeContents = TypeContents { bits: $bits };)+
2144 def_type_content_sets!(
2146 None = 0b0000_0000__0000_0000__0000,
2148 // Things that are interior to the value (first nibble):
2149 InteriorUnsized = 0b0000_0000__0000_0000__0001,
2150 InteriorUnsafe = 0b0000_0000__0000_0000__0010,
2151 // InteriorAll = 0b00000000__00000000__1111,
2153 // Things that are owned by the value (second and third nibbles):
2154 OwnsOwned = 0b0000_0000__0000_0001__0000,
2155 OwnsDtor = 0b0000_0000__0000_0010__0000,
2156 OwnsManaged /* see [1] below */ = 0b0000_0000__0000_0100__0000,
2157 OwnsAffine = 0b0000_0000__0000_1000__0000,
2158 OwnsAll = 0b0000_0000__1111_1111__0000,
2160 // Things that are reachable by the value in any way (fourth nibble):
2161 ReachesNonsendAnnot = 0b0000_0001__0000_0000__0000,
2162 ReachesBorrowed = 0b0000_0010__0000_0000__0000,
2163 // ReachesManaged /* see [1] below */ = 0b0000_0100__0000_0000__0000,
2164 ReachesMutable = 0b0000_1000__0000_0000__0000,
2165 ReachesNoSync = 0b0001_0000__0000_0000__0000,
2166 ReachesFfiUnsafe = 0b0010_0000__0000_0000__0000,
2167 ReachesAll = 0b0011_1111__0000_0000__0000,
2169 // Things that cause values to *move* rather than *copy*
2170 Moves = 0b0000_0000__0000_1011__0000,
2172 // Things that mean drop glue is necessary
2173 NeedsDrop = 0b0000_0000__0000_0111__0000,
2175 // Things that prevent values from being sent
2177 // Note: For checking whether something is sendable, it'd
2178 // be sufficient to have ReachesManaged. However, we include
2179 // both ReachesManaged and OwnsManaged so that when
2180 // a parameter has a bound T:Send, we are able to deduce
2181 // that it neither reaches nor owns a managed pointer.
2182 Nonsendable = 0b0000_0111__0000_0100__0000,
2184 // Things that prevent values from being considered sized
2185 Nonsized = 0b0000_0000__0000_0000__0001,
2187 // Things that prevent values from being sync
2188 Nonsync = 0b0001_0000__0000_0000__0000,
2190 // Things that make values considered not POD (would be same
2191 // as `Moves`, but for the fact that managed data `@` is
2192 // not considered POD)
2193 Noncopy = 0b0000_0000__0000_1111__0000,
2195 // Bits to set when a managed value is encountered
2197 // [1] Do not set the bits TC::OwnsManaged or
2198 // TC::ReachesManaged directly, instead reference
2199 // TC::Managed to set them both at once.
2200 Managed = 0b0000_0100__0000_0100__0000,
2203 All = 0b1111_1111__1111_1111__1111
2208 pub fn meets_builtin_bound(&self, cx: &ctxt, bb: BuiltinBound) -> bool {
2210 BoundSend => self.is_sendable(cx),
2211 BoundSized => self.is_sized(cx),
2212 BoundCopy => self.is_copy(cx),
2213 BoundSync => self.is_sync(cx),
2217 pub fn when(&self, cond: bool) -> TypeContents {
2218 if cond {*self} else {TC::None}
2221 pub fn intersects(&self, tc: TypeContents) -> bool {
2222 (self.bits & tc.bits) != 0
2225 pub fn is_sendable(&self, _: &ctxt) -> bool {
2226 !self.intersects(TC::Nonsendable)
2229 pub fn is_sync(&self, _: &ctxt) -> bool {
2230 !self.intersects(TC::Nonsync)
2233 pub fn owns_managed(&self) -> bool {
2234 self.intersects(TC::OwnsManaged)
2237 pub fn owns_owned(&self) -> bool {
2238 self.intersects(TC::OwnsOwned)
2241 pub fn is_sized(&self, _: &ctxt) -> bool {
2242 !self.intersects(TC::Nonsized)
2245 pub fn is_copy(&self, _: &ctxt) -> bool {
2246 !self.intersects(TC::Noncopy)
2249 pub fn interior_unsafe(&self) -> bool {
2250 self.intersects(TC::InteriorUnsafe)
2253 pub fn interior_unsized(&self) -> bool {
2254 self.intersects(TC::InteriorUnsized)
2257 pub fn moves_by_default(&self, _: &ctxt) -> bool {
2258 self.intersects(TC::Moves)
2261 pub fn needs_drop(&self, _: &ctxt) -> bool {
2262 self.intersects(TC::NeedsDrop)
2265 pub fn owned_pointer(&self) -> TypeContents {
2267 * Includes only those bits that still apply
2268 * when indirected through a `Box` pointer
2271 *self & (TC::OwnsAll | TC::ReachesAll))
2274 pub fn reference(&self, bits: TypeContents) -> TypeContents {
2276 * Includes only those bits that still apply
2277 * when indirected through a reference (`&`)
2280 *self & TC::ReachesAll)
2283 pub fn managed_pointer(&self) -> TypeContents {
2285 * Includes only those bits that still apply
2286 * when indirected through a managed pointer (`@`)
2289 *self & TC::ReachesAll)
2292 pub fn unsafe_pointer(&self) -> TypeContents {
2294 * Includes only those bits that still apply
2295 * when indirected through an unsafe pointer (`*`)
2297 *self & TC::ReachesAll
2300 pub fn union<T>(v: &[T], f: |&T| -> TypeContents) -> TypeContents {
2301 v.iter().fold(TC::None, |tc, t| tc | f(t))
2304 pub fn has_dtor(&self) -> bool {
2305 self.intersects(TC::OwnsDtor)
2309 impl ops::BitOr<TypeContents,TypeContents> for TypeContents {
2310 fn bitor(&self, other: &TypeContents) -> TypeContents {
2311 TypeContents {bits: self.bits | other.bits}
2315 impl ops::BitAnd<TypeContents,TypeContents> for TypeContents {
2316 fn bitand(&self, other: &TypeContents) -> TypeContents {
2317 TypeContents {bits: self.bits & other.bits}
2321 impl ops::Sub<TypeContents,TypeContents> for TypeContents {
2322 fn sub(&self, other: &TypeContents) -> TypeContents {
2323 TypeContents {bits: self.bits & !other.bits}
2327 impl fmt::Show for TypeContents {
2328 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
2329 write!(f, "TypeContents({:t})", self.bits)
2333 pub fn type_is_sendable(cx: &ctxt, t: ty::t) -> bool {
2334 type_contents(cx, t).is_sendable(cx)
2337 pub fn type_interior_is_unsafe(cx: &ctxt, t: ty::t) -> bool {
2338 type_contents(cx, t).interior_unsafe()
2341 pub fn type_contents(cx: &ctxt, ty: t) -> TypeContents {
2342 let ty_id = type_id(ty);
2344 match cx.tc_cache.borrow().find(&ty_id) {
2345 Some(tc) => { return *tc; }
2349 let mut cache = HashMap::new();
2350 let result = tc_ty(cx, ty, &mut cache);
2352 cx.tc_cache.borrow_mut().insert(ty_id, result);
2357 cache: &mut HashMap<uint, TypeContents>) -> TypeContents
2359 // Subtle: Note that we are *not* using cx.tc_cache here but rather a
2360 // private cache for this walk. This is needed in the case of cyclic
2363 // struct List { next: Box<Option<List>>, ... }
2365 // When computing the type contents of such a type, we wind up deeply
2366 // recursing as we go. So when we encounter the recursive reference
2367 // to List, we temporarily use TC::None as its contents. Later we'll
2368 // patch up the cache with the correct value, once we've computed it
2369 // (this is basically a co-inductive process, if that helps). So in
2370 // the end we'll compute TC::OwnsOwned, in this case.
2372 // The problem is, as we are doing the computation, we will also
2373 // compute an *intermediate* contents for, e.g., Option<List> of
2374 // TC::None. This is ok during the computation of List itself, but if
2375 // we stored this intermediate value into cx.tc_cache, then later
2376 // requests for the contents of Option<List> would also yield TC::None
2377 // which is incorrect. This value was computed based on the crutch
2378 // value for the type contents of list. The correct value is
2379 // TC::OwnsOwned. This manifested as issue #4821.
2380 let ty_id = type_id(ty);
2381 match cache.find(&ty_id) {
2382 Some(tc) => { return *tc; }
2385 match cx.tc_cache.borrow().find(&ty_id) { // Must check both caches!
2386 Some(tc) => { return *tc; }
2389 cache.insert(ty_id, TC::None);
2391 let result = match get(ty).sty {
2392 // uint and int are ffi-unsafe
2393 ty_uint(ast::TyU) | ty_int(ast::TyI) => {
2394 TC::ReachesFfiUnsafe
2397 // Scalar and unique types are sendable, and durable
2398 ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
2399 ty_bare_fn(_) | ty::ty_char => {
2403 ty_closure(ref c) => {
2404 closure_contents(cx, &**c) | TC::ReachesFfiUnsafe
2408 tc_ty(cx, typ, cache).managed_pointer() | TC::ReachesFfiUnsafe
2412 TC::ReachesFfiUnsafe | match get(typ).sty {
2413 ty_str => TC::OwnsOwned,
2414 _ => tc_ty(cx, typ, cache).owned_pointer(),
2418 ty_trait(box ty::TyTrait { bounds, .. }) => {
2419 object_contents(cx, bounds) | TC::ReachesFfiUnsafe | TC::Nonsized
2423 tc_ty(cx, mt.ty, cache).unsafe_pointer()
2426 ty_rptr(r, ref mt) => {
2427 TC::ReachesFfiUnsafe | match get(mt.ty).sty {
2428 ty_str => borrowed_contents(r, ast::MutImmutable),
2429 ty_vec(..) => tc_ty(cx, mt.ty, cache).reference(borrowed_contents(r, mt.mutbl)),
2430 _ => tc_ty(cx, mt.ty, cache).reference(borrowed_contents(r, mt.mutbl)),
2434 ty_vec(t, Some(_)) => {
2438 ty_vec(t, None) => {
2439 tc_ty(cx, t, cache) | TC::Nonsized
2441 ty_str => TC::Nonsized,
2443 ty_struct(did, ref substs) => {
2444 let flds = struct_fields(cx, did, substs);
2446 TypeContents::union(flds.as_slice(),
2447 |f| tc_mt(cx, f.mt, cache));
2449 if !lookup_repr_hints(cx, did).contains(&attr::ReprExtern) {
2450 res = res | TC::ReachesFfiUnsafe;
2453 if ty::has_dtor(cx, did) {
2454 res = res | TC::OwnsDtor;
2456 apply_lang_items(cx, did, res)
2459 ty_unboxed_closure(did, r) => {
2460 // FIXME(#14449): `borrowed_contents` below assumes `&mut`
2462 let upvars = unboxed_closure_upvars(cx, did);
2463 TypeContents::union(upvars.as_slice(),
2464 |f| tc_ty(cx, f.ty, cache)) |
2465 borrowed_contents(r, MutMutable)
2468 ty_tup(ref tys) => {
2469 TypeContents::union(tys.as_slice(),
2470 |ty| tc_ty(cx, *ty, cache))
2473 ty_enum(did, ref substs) => {
2474 let variants = substd_enum_variants(cx, did, substs);
2476 TypeContents::union(variants.as_slice(), |variant| {
2477 TypeContents::union(variant.args.as_slice(),
2479 tc_ty(cx, *arg_ty, cache)
2483 if ty::has_dtor(cx, did) {
2484 res = res | TC::OwnsDtor;
2487 if variants.len() != 0 {
2488 let repr_hints = lookup_repr_hints(cx, did);
2489 if repr_hints.len() > 1 {
2490 // this is an error later on, but this type isn't safe
2491 res = res | TC::ReachesFfiUnsafe;
2494 match repr_hints.as_slice().get(0) {
2495 Some(h) => if !h.is_ffi_safe() {
2496 res = res | TC::ReachesFfiUnsafe;
2500 res = res | TC::ReachesFfiUnsafe;
2502 // We allow ReprAny enums if they are eligible for
2503 // the nullable pointer optimization and the
2504 // contained type is an `extern fn`
2506 if variants.len() == 2 {
2507 let mut data_idx = 0;
2509 if variants.get(0).args.len() == 0 {
2513 if variants.get(data_idx).args.len() == 1 {
2514 match get(*variants.get(data_idx).args.get(0)).sty {
2515 ty_bare_fn(..) => { res = res - TC::ReachesFfiUnsafe; }
2525 apply_lang_items(cx, did, res)
2529 // We only ever ask for the kind of types that are defined in
2530 // the current crate; therefore, the only type parameters that
2531 // could be in scope are those defined in the current crate.
2532 // If this assertion failures, it is likely because of a
2533 // failure in the cross-crate inlining code to translate a
2535 assert_eq!(p.def_id.krate, ast::LOCAL_CRATE);
2537 let ty_param_defs = cx.ty_param_defs.borrow();
2538 let tp_def = ty_param_defs.get(&p.def_id.node);
2539 kind_bounds_to_contents(
2541 tp_def.bounds.builtin_bounds,
2542 tp_def.bounds.trait_bounds.as_slice())
2546 // This occurs during coherence, but shouldn't occur at other
2552 let result = tc_ty(cx, t, cache);
2553 assert!(!result.is_sized(cx))
2554 result.unsafe_pointer() | TC::Nonsized
2558 cx.sess.bug("asked to compute contents of error type");
2562 cache.insert(ty_id, result);
2568 cache: &mut HashMap<uint, TypeContents>) -> TypeContents
2570 let mc = TC::ReachesMutable.when(mt.mutbl == MutMutable);
2571 mc | tc_ty(cx, mt.ty, cache)
2574 fn apply_lang_items(cx: &ctxt,
2578 if Some(did) == cx.lang_items.no_send_bound() {
2579 tc | TC::ReachesNonsendAnnot
2580 } else if Some(did) == cx.lang_items.managed_bound() {
2582 } else if Some(did) == cx.lang_items.no_copy_bound() {
2584 } else if Some(did) == cx.lang_items.no_sync_bound() {
2585 tc | TC::ReachesNoSync
2586 } else if Some(did) == cx.lang_items.unsafe_type() {
2587 // FIXME(#13231): This shouldn't be needed after
2588 // opt-in built-in bounds are implemented.
2589 (tc | TC::InteriorUnsafe) - TC::Nonsync
2595 fn borrowed_contents(region: ty::Region,
2596 mutbl: ast::Mutability)
2599 * Type contents due to containing a reference
2600 * with the region `region` and borrow kind `bk`
2603 let b = match mutbl {
2604 ast::MutMutable => TC::ReachesMutable | TC::OwnsAffine,
2605 ast::MutImmutable => TC::None,
2607 b | (TC::ReachesBorrowed).when(region != ty::ReStatic)
2610 fn closure_contents(cx: &ctxt, cty: &ClosureTy) -> TypeContents {
2611 // Closure contents are just like trait contents, but with potentially
2613 let st = object_contents(cx, cty.bounds);
2615 let st = match cty.store {
2619 RegionTraitStore(r, mutbl) => {
2620 st.reference(borrowed_contents(r, mutbl))
2624 // This also prohibits "@once fn" from being copied, which allows it to
2625 // be called. Neither way really makes much sense.
2626 let ot = match cty.onceness {
2627 ast::Once => TC::OwnsAffine,
2628 ast::Many => TC::None,
2634 fn object_contents(cx: &ctxt,
2635 bounds: ExistentialBounds)
2637 // These are the type contents of the (opaque) interior
2638 kind_bounds_to_contents(cx, bounds.builtin_bounds, [])
2641 fn kind_bounds_to_contents(cx: &ctxt,
2642 bounds: BuiltinBounds,
2643 traits: &[Rc<TraitRef>])
2645 let _i = indenter();
2646 let mut tc = TC::All;
2647 each_inherited_builtin_bound(cx, bounds, traits, |bound| {
2648 tc = tc - match bound {
2649 BoundSend => TC::Nonsendable,
2650 BoundSized => TC::Nonsized,
2651 BoundCopy => TC::Noncopy,
2652 BoundSync => TC::Nonsync,
2657 // Iterates over all builtin bounds on the type parameter def, including
2658 // those inherited from traits with builtin-kind-supertraits.
2659 fn each_inherited_builtin_bound(cx: &ctxt,
2660 bounds: BuiltinBounds,
2661 traits: &[Rc<TraitRef>],
2662 f: |BuiltinBound|) {
2663 for bound in bounds.iter() {
2667 each_bound_trait_and_supertraits(cx, traits, |trait_ref| {
2668 let trait_def = lookup_trait_def(cx, trait_ref.def_id);
2669 for bound in trait_def.bounds.builtin_bounds.iter() {
2678 pub fn type_moves_by_default(cx: &ctxt, ty: t) -> bool {
2679 type_contents(cx, ty).moves_by_default(cx)
2682 pub fn is_ffi_safe(cx: &ctxt, ty: t) -> bool {
2683 !type_contents(cx, ty).intersects(TC::ReachesFfiUnsafe)
2686 // True if instantiating an instance of `r_ty` requires an instance of `r_ty`.
2687 pub fn is_instantiable(cx: &ctxt, r_ty: t) -> bool {
2688 fn type_requires(cx: &ctxt, seen: &mut Vec<DefId>,
2689 r_ty: t, ty: t) -> bool {
2690 debug!("type_requires({}, {})?",
2691 ::util::ppaux::ty_to_string(cx, r_ty),
2692 ::util::ppaux::ty_to_string(cx, ty));
2695 get(r_ty).sty == get(ty).sty ||
2696 subtypes_require(cx, seen, r_ty, ty)
2699 debug!("type_requires({}, {})? {}",
2700 ::util::ppaux::ty_to_string(cx, r_ty),
2701 ::util::ppaux::ty_to_string(cx, ty),
2706 fn subtypes_require(cx: &ctxt, seen: &mut Vec<DefId>,
2707 r_ty: t, ty: t) -> bool {
2708 debug!("subtypes_require({}, {})?",
2709 ::util::ppaux::ty_to_string(cx, r_ty),
2710 ::util::ppaux::ty_to_string(cx, ty));
2712 let r = match get(ty).sty {
2713 // fixed length vectors need special treatment compared to
2714 // normal vectors, since they don't necessarily have the
2715 // possibility to have length zero.
2716 ty_vec(_, Some(0)) => false, // don't need no contents
2717 ty_vec(ty, Some(_)) => type_requires(cx, seen, r_ty, ty),
2732 ty_vec(_, None) => {
2735 ty_box(typ) | ty_uniq(typ) | ty_open(typ) => {
2736 type_requires(cx, seen, r_ty, typ)
2738 ty_rptr(_, ref mt) => {
2739 type_requires(cx, seen, r_ty, mt.ty)
2743 false // unsafe ptrs can always be NULL
2750 ty_struct(ref did, _) if seen.contains(did) => {
2754 ty_struct(did, ref substs) => {
2756 let fields = struct_fields(cx, did, substs);
2757 let r = fields.iter().any(|f| type_requires(cx, seen, r_ty, f.mt.ty));
2758 seen.pop().unwrap();
2762 ty_unboxed_closure(did, _) => {
2763 let upvars = unboxed_closure_upvars(cx, did);
2764 upvars.iter().any(|f| type_requires(cx, seen, r_ty, f.ty))
2768 ts.iter().any(|t| type_requires(cx, seen, r_ty, *t))
2771 ty_enum(ref did, _) if seen.contains(did) => {
2775 ty_enum(did, ref substs) => {
2777 let vs = enum_variants(cx, did);
2778 let r = !vs.is_empty() && vs.iter().all(|variant| {
2779 variant.args.iter().any(|aty| {
2780 let sty = aty.subst(cx, substs);
2781 type_requires(cx, seen, r_ty, sty)
2784 seen.pop().unwrap();
2789 debug!("subtypes_require({}, {})? {}",
2790 ::util::ppaux::ty_to_string(cx, r_ty),
2791 ::util::ppaux::ty_to_string(cx, ty),
2797 let mut seen = Vec::new();
2798 !subtypes_require(cx, &mut seen, r_ty, r_ty)
2801 /// Describes whether a type is representable. For types that are not
2802 /// representable, 'SelfRecursive' and 'ContainsRecursive' are used to
2803 /// distinguish between types that are recursive with themselves and types that
2804 /// contain a different recursive type. These cases can therefore be treated
2805 /// differently when reporting errors.
2806 #[deriving(PartialEq)]
2807 pub enum Representability {
2813 /// Check whether a type is representable. This means it cannot contain unboxed
2814 /// structural recursion. This check is needed for structs and enums.
2815 pub fn is_type_representable(cx: &ctxt, sp: Span, ty: t) -> Representability {
2817 // Iterate until something non-representable is found
2818 fn find_nonrepresentable<It: Iterator<t>>(cx: &ctxt, sp: Span, seen: &mut Vec<DefId>,
2819 mut iter: It) -> Representability {
2821 let r = type_structurally_recursive(cx, sp, seen, ty);
2822 if r != Representable {
2829 // Does the type `ty` directly (without indirection through a pointer)
2830 // contain any types on stack `seen`?
2831 fn type_structurally_recursive(cx: &ctxt, sp: Span, seen: &mut Vec<DefId>,
2832 ty: t) -> Representability {
2833 debug!("type_structurally_recursive: {}",
2834 ::util::ppaux::ty_to_string(cx, ty));
2836 // Compare current type to previously seen types
2839 ty_enum(did, _) => {
2840 for (i, &seen_did) in seen.iter().enumerate() {
2841 if did == seen_did {
2842 return if i == 0 { SelfRecursive }
2843 else { ContainsRecursive }
2850 // Check inner types
2854 find_nonrepresentable(cx, sp, seen, ts.iter().map(|t| *t))
2856 // Fixed-length vectors.
2857 // FIXME(#11924) Behavior undecided for zero-length vectors.
2858 ty_vec(ty, Some(_)) => {
2859 type_structurally_recursive(cx, sp, seen, ty)
2862 // Push struct and enum def-ids onto `seen` before recursing.
2863 ty_struct(did, ref substs) => {
2865 let fields = struct_fields(cx, did, substs);
2866 let r = find_nonrepresentable(cx, sp, seen,
2867 fields.iter().map(|f| f.mt.ty));
2872 ty_enum(did, ref substs) => {
2874 let vs = enum_variants(cx, did);
2876 let mut r = Representable;
2877 for variant in vs.iter() {
2878 let iter = variant.args.iter().map(|aty| {
2879 aty.subst_spanned(cx, substs, Some(sp))
2881 r = find_nonrepresentable(cx, sp, seen, iter);
2883 if r != Representable { break }
2890 ty_unboxed_closure(did, _) => {
2891 let upvars = unboxed_closure_upvars(cx, did);
2892 find_nonrepresentable(cx,
2895 upvars.iter().map(|f| f.ty))
2902 debug!("is_type_representable: {}",
2903 ::util::ppaux::ty_to_string(cx, ty));
2905 // To avoid a stack overflow when checking an enum variant or struct that
2906 // contains a different, structurally recursive type, maintain a stack
2907 // of seen types and check recursion for each of them (issues #3008, #3779).
2908 let mut seen: Vec<DefId> = Vec::new();
2909 type_structurally_recursive(cx, sp, &mut seen, ty)
2912 pub fn type_is_trait(ty: t) -> bool {
2914 ty_uniq(ty) | ty_rptr(_, mt { ty, ..}) | ty_ptr(mt { ty, ..}) => match get(ty).sty {
2915 ty_trait(..) => true,
2918 ty_trait(..) => true,
2923 pub fn type_is_integral(ty: t) -> bool {
2925 ty_infer(IntVar(_)) | ty_int(_) | ty_uint(_) => true,
2930 pub fn type_is_uint(ty: t) -> bool {
2932 ty_infer(IntVar(_)) | ty_uint(ast::TyU) => true,
2937 pub fn type_is_char(ty: t) -> bool {
2944 pub fn type_is_bare_fn(ty: t) -> bool {
2946 ty_bare_fn(..) => true,
2951 pub fn type_is_fp(ty: t) -> bool {
2953 ty_infer(FloatVar(_)) | ty_float(_) => true,
2958 pub fn type_is_numeric(ty: t) -> bool {
2959 return type_is_integral(ty) || type_is_fp(ty);
2962 pub fn type_is_signed(ty: t) -> bool {
2969 pub fn type_is_machine(ty: t) -> bool {
2971 ty_int(ast::TyI) | ty_uint(ast::TyU) => false,
2972 ty_int(..) | ty_uint(..) | ty_float(..) => true,
2977 // Is the type's representation size known at compile time?
2978 pub fn type_is_sized(cx: &ctxt, ty: t) -> bool {
2979 type_contents(cx, ty).is_sized(cx)
2982 pub fn lltype_is_sized(cx: &ctxt, ty: t) -> bool {
2985 _ => type_contents(cx, ty).is_sized(cx)
2989 // Return the smallest part of t which is unsized. Fails if t is sized.
2990 // 'Smallest' here means component of the static representation of the type; not
2991 // the size of an object at runtime.
2992 pub fn unsized_part_of_type(cx: &ctxt, ty: t) -> t {
2994 ty_str | ty_trait(..) | ty_vec(..) => ty,
2995 ty_struct(def_id, ref substs) => {
2996 let unsized_fields: Vec<_> = struct_fields(cx, def_id, substs).iter()
2997 .map(|f| f.mt.ty).filter(|ty| !type_is_sized(cx, *ty)).collect();
2998 // Exactly one of the fields must be unsized.
2999 assert!(unsized_fields.len() == 1)
3001 unsized_part_of_type(cx, unsized_fields[0])
3004 assert!(type_is_sized(cx, ty),
3005 "unsized_part_of_type failed even though ty is unsized");
3006 fail!("called unsized_part_of_type with sized ty");
3011 // Whether a type is enum like, that is an enum type with only nullary
3013 pub fn type_is_c_like_enum(cx: &ctxt, ty: t) -> bool {
3015 ty_enum(did, _) => {
3016 let variants = enum_variants(cx, did);
3017 if variants.len() == 0 {
3020 variants.iter().all(|v| v.args.len() == 0)
3027 // Returns the type and mutability of *t.
3029 // The parameter `explicit` indicates if this is an *explicit* dereference.
3030 // Some types---notably unsafe ptrs---can only be dereferenced explicitly.
3031 pub fn deref(t: t, explicit: bool) -> Option<mt> {
3033 ty_box(ty) | ty_uniq(ty) => {
3036 mutbl: ast::MutImmutable,
3039 ty_rptr(_, mt) => Some(mt),
3040 ty_ptr(mt) if explicit => Some(mt),
3045 pub fn deref_or_dont(t: t) -> t {
3047 ty_box(ty) | ty_uniq(ty) => {
3050 ty_rptr(_, mt) | ty_ptr(mt) => mt.ty,
3055 pub fn close_type(cx: &ctxt, t: t) -> t {
3057 ty_open(t) => mk_rptr(cx, ReStatic, mt {ty: t, mutbl:ast::MutImmutable}),
3058 _ => cx.sess.bug(format!("Trying to close a non-open type {}",
3059 ty_to_string(cx, t)).as_slice())
3063 pub fn type_content(t: t) -> t {
3065 ty_box(ty) | ty_uniq(ty) => ty,
3066 ty_rptr(_, mt) |ty_ptr(mt) => mt.ty,
3072 // Extract the unsized type in an open type (or just return t if it is not open).
3073 pub fn unopen_type(t: t) -> t {
3080 // Returns the type of t[i]
3081 pub fn index(ty: t) -> Option<t> {
3083 ty_vec(t, _) => Some(t),
3088 // Returns the type of elements contained within an 'array-like' type.
3089 // This is exactly the same as the above, except it supports strings,
3090 // which can't actually be indexed.
3091 pub fn array_element_ty(t: t) -> Option<t> {
3093 ty_vec(t, _) => Some(t),
3094 ty_str => Some(mk_u8()),
3099 pub fn node_id_to_trait_ref(cx: &ctxt, id: ast::NodeId) -> Rc<ty::TraitRef> {
3100 match cx.trait_refs.borrow().find(&id) {
3101 Some(t) => t.clone(),
3102 None => cx.sess.bug(
3103 format!("node_id_to_trait_ref: no trait ref for node `{}`",
3104 cx.map.node_to_string(id)).as_slice())
3108 pub fn try_node_id_to_type(cx: &ctxt, id: ast::NodeId) -> Option<t> {
3109 cx.node_types.borrow().find_copy(&(id as uint))
3112 pub fn node_id_to_type(cx: &ctxt, id: ast::NodeId) -> t {
3113 match try_node_id_to_type(cx, id) {
3115 None => cx.sess.bug(
3116 format!("node_id_to_type: no type for node `{}`",
3117 cx.map.node_to_string(id)).as_slice())
3121 pub fn node_id_to_type_opt(cx: &ctxt, id: ast::NodeId) -> Option<t> {
3122 match cx.node_types.borrow().find(&(id as uint)) {
3123 Some(&t) => Some(t),
3128 pub fn node_id_item_substs(cx: &ctxt, id: ast::NodeId) -> ItemSubsts {
3129 match cx.item_substs.borrow().find(&id) {
3130 None => ItemSubsts::empty(),
3131 Some(ts) => ts.clone(),
3135 pub fn fn_is_variadic(fty: t) -> bool {
3136 match get(fty).sty {
3137 ty_bare_fn(ref f) => f.sig.variadic,
3138 ty_closure(ref f) => f.sig.variadic,
3140 fail!("fn_is_variadic() called on non-fn type: {:?}", s)
3145 pub fn ty_fn_sig(fty: t) -> FnSig {
3146 match get(fty).sty {
3147 ty_bare_fn(ref f) => f.sig.clone(),
3148 ty_closure(ref f) => f.sig.clone(),
3150 fail!("ty_fn_sig() called on non-fn type: {:?}", s)
3155 /// Returns the ABI of the given function.
3156 pub fn ty_fn_abi(fty: t) -> abi::Abi {
3157 match get(fty).sty {
3158 ty_bare_fn(ref f) => f.abi,
3159 ty_closure(ref f) => f.abi,
3160 _ => fail!("ty_fn_abi() called on non-fn type"),
3164 // Type accessors for substructures of types
3165 pub fn ty_fn_args(fty: t) -> Vec<t> {
3166 match get(fty).sty {
3167 ty_bare_fn(ref f) => f.sig.inputs.clone(),
3168 ty_closure(ref f) => f.sig.inputs.clone(),
3170 fail!("ty_fn_args() called on non-fn type: {:?}", s)
3175 pub fn ty_closure_store(fty: t) -> TraitStore {
3176 match get(fty).sty {
3177 ty_closure(ref f) => f.store,
3178 ty_unboxed_closure(..) => {
3179 // Close enough for the purposes of all the callers of this
3180 // function (which is soon to be deprecated anyhow).
3184 fail!("ty_closure_store() called on non-closure type: {:?}", s)
3189 pub fn ty_fn_ret(fty: t) -> t {
3190 match get(fty).sty {
3191 ty_bare_fn(ref f) => f.sig.output,
3192 ty_closure(ref f) => f.sig.output,
3194 fail!("ty_fn_ret() called on non-fn type: {:?}", s)
3199 pub fn is_fn_ty(fty: t) -> bool {
3200 match get(fty).sty {
3201 ty_bare_fn(_) => true,
3202 ty_closure(_) => true,
3207 pub fn ty_region(tcx: &ctxt,
3215 format!("ty_region() invoked on in appropriate ty: {:?}",
3221 pub fn free_region_from_def(free_id: ast::NodeId, def: &RegionParameterDef)
3224 ty::ReFree(ty::FreeRegion { scope_id: free_id,
3225 bound_region: ty::BrNamed(def.def_id,
3229 // Returns the type of a pattern as a monotype. Like @expr_ty, this function
3230 // doesn't provide type parameter substitutions.
3231 pub fn pat_ty(cx: &ctxt, pat: &ast::Pat) -> t {
3232 return node_id_to_type(cx, pat.id);
3236 // Returns the type of an expression as a monotype.
3238 // NB (1): This is the PRE-ADJUSTMENT TYPE for the expression. That is, in
3239 // some cases, we insert `AutoAdjustment` annotations such as auto-deref or
3240 // auto-ref. The type returned by this function does not consider such
3241 // adjustments. See `expr_ty_adjusted()` instead.
3243 // NB (2): This type doesn't provide type parameter substitutions; e.g. if you
3244 // ask for the type of "id" in "id(3)", it will return "fn(&int) -> int"
3245 // instead of "fn(t) -> T with T = int".
3246 pub fn expr_ty(cx: &ctxt, expr: &ast::Expr) -> t {
3247 return node_id_to_type(cx, expr.id);
3250 pub fn expr_ty_opt(cx: &ctxt, expr: &ast::Expr) -> Option<t> {
3251 return node_id_to_type_opt(cx, expr.id);
3254 pub fn expr_ty_adjusted(cx: &ctxt, expr: &ast::Expr) -> t {
3257 * Returns the type of `expr`, considering any `AutoAdjustment`
3258 * entry recorded for that expression.
3260 * It would almost certainly be better to store the adjusted ty in with
3261 * the `AutoAdjustment`, but I opted not to do this because it would
3262 * require serializing and deserializing the type and, although that's not
3263 * hard to do, I just hate that code so much I didn't want to touch it
3264 * unless it was to fix it properly, which seemed a distraction from the
3265 * task at hand! -nmatsakis
3268 adjust_ty(cx, expr.span, expr.id, expr_ty(cx, expr),
3269 cx.adjustments.borrow().find(&expr.id),
3270 |method_call| cx.method_map.borrow().find(&method_call).map(|method| method.ty))
3273 pub fn expr_span(cx: &ctxt, id: NodeId) -> Span {
3274 match cx.map.find(id) {
3275 Some(ast_map::NodeExpr(e)) => {
3279 cx.sess.bug(format!("Node id {} is not an expr: {:?}",
3284 cx.sess.bug(format!("Node id {} is not present \
3285 in the node map", id).as_slice());
3290 pub fn local_var_name_str(cx: &ctxt, id: NodeId) -> InternedString {
3291 match cx.map.find(id) {
3292 Some(ast_map::NodeLocal(pat)) => {
3294 ast::PatIdent(_, ref path1, _) => {
3295 token::get_ident(path1.node)
3299 format!("Variable id {} maps to {:?}, not local",
3306 cx.sess.bug(format!("Variable id {} maps to {:?}, not local",
3313 pub fn adjust_ty(cx: &ctxt,
3315 expr_id: ast::NodeId,
3316 unadjusted_ty: ty::t,
3317 adjustment: Option<&AutoAdjustment>,
3318 method_type: |typeck::MethodCall| -> Option<ty::t>)
3320 /*! See `expr_ty_adjusted` */
3322 match get(unadjusted_ty).sty {
3323 ty_err => return unadjusted_ty,
3327 return match adjustment {
3328 Some(adjustment) => {
3330 AutoAddEnv(store) => {
3331 match ty::get(unadjusted_ty).sty {
3332 ty::ty_bare_fn(ref b) => {
3333 let bounds = ty::ExistentialBounds {
3334 region_bound: ReStatic,
3335 builtin_bounds: all_builtin_bounds(),
3340 ty::ClosureTy {fn_style: b.fn_style,
3341 onceness: ast::Many,
3349 format!("add_env adjustment on non-bare-fn: \
3356 AutoDerefRef(ref adj) => {
3357 let mut adjusted_ty = unadjusted_ty;
3359 if !ty::type_is_error(adjusted_ty) {
3360 for i in range(0, adj.autoderefs) {
3361 let method_call = typeck::MethodCall::autoderef(expr_id, i);
3362 match method_type(method_call) {
3363 Some(method_ty) => {
3364 adjusted_ty = ty_fn_ret(method_ty);
3368 match deref(adjusted_ty, true) {
3369 Some(mt) => { adjusted_ty = mt.ty; }
3373 format!("the {}th autoderef failed: \
3376 ty_to_string(cx, adjusted_ty))
3384 None => adjusted_ty,
3385 Some(ref autoref) => adjust_for_autoref(cx, span, adjusted_ty, autoref)
3390 None => unadjusted_ty
3393 fn adjust_for_autoref(cx: &ctxt,
3396 autoref: &AutoRef) -> ty::t{
3398 AutoPtr(r, m, ref a) => {
3399 let adjusted_ty = match a {
3400 &Some(box ref a) => adjust_for_autoref(cx, span, ty, a),
3409 AutoUnsafe(m, ref a) => {
3410 let adjusted_ty = match a {
3411 &Some(box ref a) => adjust_for_autoref(cx, span, ty, a),
3414 mk_ptr(cx, mt {ty: adjusted_ty, mutbl: m})
3417 AutoUnsize(ref k) => unsize_ty(cx, ty, k, span),
3418 AutoUnsizeUniq(ref k) => ty::mk_uniq(cx, unsize_ty(cx, ty, k, span)),
3423 // Take a sized type and a sizing adjustment and produce an unsized version of
3425 pub fn unsize_ty(cx: &ctxt,
3431 &UnsizeLength(len) => match get(ty).sty {
3432 ty_vec(t, Some(n)) => {
3436 _ => cx.sess.span_bug(span,
3437 format!("UnsizeLength with bad sty: {}",
3438 ty_to_string(cx, ty)).as_slice())
3440 &UnsizeStruct(box ref k, tp_index) => match get(ty).sty {
3441 ty_struct(did, ref substs) => {
3442 let ty_substs = substs.types.get_slice(subst::TypeSpace);
3443 let new_ty = unsize_ty(cx, ty_substs[tp_index], k, span);
3444 let mut unsized_substs = substs.clone();
3445 unsized_substs.types.get_mut_slice(subst::TypeSpace)[tp_index] = new_ty;
3446 mk_struct(cx, did, unsized_substs)
3448 _ => cx.sess.span_bug(span,
3449 format!("UnsizeStruct with bad sty: {}",
3450 ty_to_string(cx, ty)).as_slice())
3452 &UnsizeVtable(bounds, def_id, ref substs) => {
3453 mk_trait(cx, def_id, substs.clone(), bounds)
3459 pub fn map_region(&self, f: |Region| -> Region) -> AutoRef {
3461 ty::AutoPtr(r, m, None) => ty::AutoPtr(f(r), m, None),
3462 ty::AutoPtr(r, m, Some(ref a)) => ty::AutoPtr(f(r), m, Some(box a.map_region(f))),
3463 ty::AutoUnsize(ref k) => ty::AutoUnsize(k.clone()),
3464 ty::AutoUnsizeUniq(ref k) => ty::AutoUnsizeUniq(k.clone()),
3465 ty::AutoUnsafe(m, None) => ty::AutoUnsafe(m, None),
3466 ty::AutoUnsafe(m, Some(ref a)) => ty::AutoUnsafe(m, Some(box a.map_region(f))),
3471 pub fn method_call_type_param_defs<'tcx, T>(typer: &T,
3472 origin: typeck::MethodOrigin)
3473 -> VecPerParamSpace<TypeParameterDef>
3474 where T: mc::Typer<'tcx> {
3476 typeck::MethodStatic(did) => {
3477 ty::lookup_item_type(typer.tcx(), did).generics.types.clone()
3479 typeck::MethodStaticUnboxedClosure(did) => {
3480 let def_id = typer.unboxed_closures()
3483 .expect("method_call_type_param_defs: didn't \
3484 find unboxed closure")
3486 .trait_did(typer.tcx());
3487 lookup_trait_def(typer.tcx(), def_id).generics.types.clone()
3489 typeck::MethodParam(typeck::MethodParam{
3494 typeck::MethodObject(typeck::MethodObject{
3499 match ty::trait_item(typer.tcx(), trt_id, n_mth) {
3500 ty::MethodTraitItem(method) => method.generics.types.clone(),
3506 pub fn resolve_expr(tcx: &ctxt, expr: &ast::Expr) -> def::Def {
3507 match tcx.def_map.borrow().find(&expr.id) {
3510 tcx.sess.span_bug(expr.span, format!(
3511 "no def-map entry for expr {:?}", expr.id).as_slice());
3516 pub fn expr_is_lval(tcx: &ctxt, e: &ast::Expr) -> bool {
3517 match expr_kind(tcx, e) {
3519 RvalueDpsExpr | RvalueDatumExpr | RvalueStmtExpr => false
3523 /// We categorize expressions into three kinds. The distinction between
3524 /// lvalue/rvalue is fundamental to the language. The distinction between the
3525 /// two kinds of rvalues is an artifact of trans which reflects how we will
3526 /// generate code for that kind of expression. See trans/expr.rs for more
3535 pub fn expr_kind(tcx: &ctxt, expr: &ast::Expr) -> ExprKind {
3536 if tcx.method_map.borrow().contains_key(&typeck::MethodCall::expr(expr.id)) {
3537 // Overloaded operations are generally calls, and hence they are
3538 // generated via DPS, but there are a few exceptions:
3539 return match expr.node {
3540 // `a += b` has a unit result.
3541 ast::ExprAssignOp(..) => RvalueStmtExpr,
3543 // the deref method invoked for `*a` always yields an `&T`
3544 ast::ExprUnary(ast::UnDeref, _) => LvalueExpr,
3546 // the index method invoked for `a[i]` always yields an `&T`
3547 ast::ExprIndex(..) => LvalueExpr,
3549 // `for` loops are statements
3550 ast::ExprForLoop(..) => RvalueStmtExpr,
3552 // in the general case, result could be any type, use DPS
3558 ast::ExprPath(..) => {
3559 match resolve_expr(tcx, expr) {
3560 def::DefVariant(tid, vid, _) => {
3561 let variant_info = enum_variant_with_id(tcx, tid, vid);
3562 if variant_info.args.len() > 0u {
3571 def::DefStruct(_) => {
3572 match get(expr_ty(tcx, expr)).sty {
3573 ty_bare_fn(..) => RvalueDatumExpr,
3578 // Fn pointers are just scalar values.
3579 def::DefFn(..) | def::DefStaticMethod(..) => RvalueDatumExpr,
3581 // Note: there is actually a good case to be made that
3582 // DefArg's, particularly those of immediate type, ought to
3583 // considered rvalues.
3584 def::DefStatic(..) |
3585 def::DefBinding(..) |
3588 def::DefLocal(..) => LvalueExpr,
3593 format!("uncategorized def for expr {:?}: {:?}",
3600 ast::ExprUnary(ast::UnDeref, _) |
3601 ast::ExprField(..) |
3602 ast::ExprTupField(..) |
3603 ast::ExprIndex(..) => {
3608 ast::ExprMethodCall(..) |
3609 ast::ExprStruct(..) |
3612 ast::ExprMatch(..) |
3613 ast::ExprFnBlock(..) |
3615 ast::ExprUnboxedFn(..) |
3616 ast::ExprBlock(..) |
3617 ast::ExprRepeat(..) |
3618 ast::ExprVec(..) => {
3622 ast::ExprLit(lit) if lit_is_str(lit) => {
3626 ast::ExprCast(..) => {
3627 match tcx.node_types.borrow().find(&(expr.id as uint)) {
3629 if type_is_trait(t) {
3636 // Technically, it should not happen that the expr is not
3637 // present within the table. However, it DOES happen
3638 // during type check, because the final types from the
3639 // expressions are not yet recorded in the tcx. At that
3640 // time, though, we are only interested in knowing lvalue
3641 // vs rvalue. It would be better to base this decision on
3642 // the AST type in cast node---but (at the time of this
3643 // writing) it's not easy to distinguish casts to traits
3644 // from other casts based on the AST. This should be
3645 // easier in the future, when casts to traits
3646 // would like @Foo, Box<Foo>, or &Foo.
3652 ast::ExprBreak(..) |
3653 ast::ExprAgain(..) |
3655 ast::ExprWhile(..) |
3657 ast::ExprAssign(..) |
3658 ast::ExprInlineAsm(..) |
3659 ast::ExprAssignOp(..) |
3660 ast::ExprForLoop(..) => {
3664 ast::ExprLit(_) | // Note: LitStr is carved out above
3665 ast::ExprUnary(..) |
3666 ast::ExprAddrOf(..) |
3667 ast::ExprBinary(..) => {
3671 ast::ExprBox(place, _) => {
3672 // Special case `Box<T>`/`Gc<T>` for now:
3673 let definition = match tcx.def_map.borrow().find(&place.id) {
3675 None => fail!("no def for place"),
3677 let def_id = definition.def_id();
3678 if tcx.lang_items.exchange_heap() == Some(def_id) ||
3679 tcx.lang_items.managed_heap() == Some(def_id) {
3686 ast::ExprParen(ref e) => expr_kind(tcx, &**e),
3688 ast::ExprMac(..) => {
3691 "macro expression remains after expansion");
3696 pub fn stmt_node_id(s: &ast::Stmt) -> ast::NodeId {
3698 ast::StmtDecl(_, id) | StmtExpr(_, id) | StmtSemi(_, id) => {
3701 ast::StmtMac(..) => fail!("unexpanded macro in trans")
3705 pub fn field_idx_strict(tcx: &ctxt, name: ast::Name, fields: &[field])
3708 for f in fields.iter() { if f.ident.name == name { return i; } i += 1u; }
3709 tcx.sess.bug(format!(
3710 "no field named `{}` found in the list of fields `{:?}`",
3711 token::get_name(name),
3713 .map(|f| token::get_ident(f.ident).get().to_string())
3714 .collect::<Vec<String>>()).as_slice());
3717 pub fn impl_or_trait_item_idx(id: ast::Ident, trait_items: &[ImplOrTraitItem])
3719 trait_items.iter().position(|m| m.ident() == id)
3722 /// Returns a vector containing the indices of all type parameters that appear
3723 /// in `ty`. The vector may contain duplicates. Probably should be converted
3724 /// to a bitset or some other representation.
3725 pub fn param_tys_in_type(ty: t) -> Vec<ParamTy> {
3726 let mut rslt = Vec::new();
3738 pub fn ty_sort_string(cx: &ctxt, t: t) -> String {
3740 ty_nil | ty_bot | ty_bool | ty_char | ty_int(_) |
3741 ty_uint(_) | ty_float(_) | ty_str => {
3742 ::util::ppaux::ty_to_string(cx, t)
3745 ty_enum(id, _) => format!("enum {}", item_path_str(cx, id)),
3746 ty_box(_) => "Gc-ptr".to_string(),
3747 ty_uniq(_) => "box".to_string(),
3748 ty_vec(_, _) => "vector".to_string(),
3749 ty_ptr(_) => "*-ptr".to_string(),
3750 ty_rptr(_, _) => "&-ptr".to_string(),
3751 ty_bare_fn(_) => "extern fn".to_string(),
3752 ty_closure(_) => "fn".to_string(),
3753 ty_trait(ref inner) => {
3754 format!("trait {}", item_path_str(cx, inner.def_id))
3756 ty_struct(id, _) => {
3757 format!("struct {}", item_path_str(cx, id))
3759 ty_unboxed_closure(..) => "closure".to_string(),
3760 ty_tup(_) => "tuple".to_string(),
3761 ty_infer(TyVar(_)) => "inferred type".to_string(),
3762 ty_infer(IntVar(_)) => "integral variable".to_string(),
3763 ty_infer(FloatVar(_)) => "floating-point variable".to_string(),
3764 ty_param(ref p) => {
3765 if p.space == subst::SelfSpace {
3768 "type parameter".to_string()
3771 ty_err => "type error".to_string(),
3772 ty_open(_) => "opened DST".to_string(),
3776 pub fn type_err_to_str(cx: &ctxt, err: &type_err) -> String {
3779 * Explains the source of a type err in a short,
3780 * human readable way. This is meant to be placed in
3781 * parentheses after some larger message. You should
3782 * also invoke `note_and_explain_type_err()` afterwards
3783 * to present additional details, particularly when
3784 * it comes to lifetime-related errors. */
3786 fn tstore_to_closure(s: &TraitStore) -> String {
3788 &UniqTraitStore => "proc".to_string(),
3789 &RegionTraitStore(..) => "closure".to_string()
3794 terr_cyclic_ty => "cyclic type of infinite size".to_string(),
3795 terr_mismatch => "types differ".to_string(),
3796 terr_fn_style_mismatch(values) => {
3797 format!("expected {} fn, found {} fn",
3798 values.expected.to_string(),
3799 values.found.to_string())
3801 terr_abi_mismatch(values) => {
3802 format!("expected {} fn, found {} fn",
3803 values.expected.to_string(),
3804 values.found.to_string())
3806 terr_onceness_mismatch(values) => {
3807 format!("expected {} fn, found {} fn",
3808 values.expected.to_string(),
3809 values.found.to_string())
3811 terr_sigil_mismatch(values) => {
3812 format!("expected {}, found {}",
3813 tstore_to_closure(&values.expected),
3814 tstore_to_closure(&values.found))
3816 terr_mutability => "values differ in mutability".to_string(),
3817 terr_box_mutability => {
3818 "boxed values differ in mutability".to_string()
3820 terr_vec_mutability => "vectors differ in mutability".to_string(),
3821 terr_ptr_mutability => "pointers differ in mutability".to_string(),
3822 terr_ref_mutability => "references differ in mutability".to_string(),
3823 terr_ty_param_size(values) => {
3824 format!("expected a type with {} type params, \
3825 found one with {} type params",
3829 terr_tuple_size(values) => {
3830 format!("expected a tuple with {} elements, \
3831 found one with {} elements",
3835 terr_record_size(values) => {
3836 format!("expected a record with {} fields, \
3837 found one with {} fields",
3841 terr_record_mutability => {
3842 "record elements differ in mutability".to_string()
3844 terr_record_fields(values) => {
3845 format!("expected a record with field `{}`, found one \
3847 token::get_ident(values.expected),
3848 token::get_ident(values.found))
3851 "incorrect number of function parameters".to_string()
3853 terr_regions_does_not_outlive(..) => {
3854 "lifetime mismatch".to_string()
3856 terr_regions_not_same(..) => {
3857 "lifetimes are not the same".to_string()
3859 terr_regions_no_overlap(..) => {
3860 "lifetimes do not intersect".to_string()
3862 terr_regions_insufficiently_polymorphic(br, _) => {
3863 format!("expected bound lifetime parameter {}, \
3864 found concrete lifetime",
3865 bound_region_ptr_to_string(cx, br))
3867 terr_regions_overly_polymorphic(br, _) => {
3868 format!("expected concrete lifetime, \
3869 found bound lifetime parameter {}",
3870 bound_region_ptr_to_string(cx, br))
3872 terr_trait_stores_differ(_, ref values) => {
3873 format!("trait storage differs: expected `{}`, found `{}`",
3874 trait_store_to_string(cx, (*values).expected),
3875 trait_store_to_string(cx, (*values).found))
3877 terr_sorts(values) => {
3878 format!("expected {}, found {}",
3879 ty_sort_string(cx, values.expected),
3880 ty_sort_string(cx, values.found))
3882 terr_traits(values) => {
3883 format!("expected trait `{}`, found trait `{}`",
3884 item_path_str(cx, values.expected),
3885 item_path_str(cx, values.found))
3887 terr_builtin_bounds(values) => {
3888 if values.expected.is_empty() {
3889 format!("expected no bounds, found `{}`",
3890 values.found.user_string(cx))
3891 } else if values.found.is_empty() {
3892 format!("expected bounds `{}`, found no bounds",
3893 values.expected.user_string(cx))
3895 format!("expected bounds `{}`, found bounds `{}`",
3896 values.expected.user_string(cx),
3897 values.found.user_string(cx))
3900 terr_integer_as_char => {
3901 "expected an integral type, found `char`".to_string()
3903 terr_int_mismatch(ref values) => {
3904 format!("expected `{}`, found `{}`",
3905 values.expected.to_string(),
3906 values.found.to_string())
3908 terr_float_mismatch(ref values) => {
3909 format!("expected `{}`, found `{}`",
3910 values.expected.to_string(),
3911 values.found.to_string())
3913 terr_variadic_mismatch(ref values) => {
3914 format!("expected {} fn, found {} function",
3915 if values.expected { "variadic" } else { "non-variadic" },
3916 if values.found { "variadic" } else { "non-variadic" })
3921 pub fn note_and_explain_type_err(cx: &ctxt, err: &type_err) {
3923 terr_regions_does_not_outlive(subregion, superregion) => {
3924 note_and_explain_region(cx, "", subregion, "...");
3925 note_and_explain_region(cx, "...does not necessarily outlive ",
3928 terr_regions_not_same(region1, region2) => {
3929 note_and_explain_region(cx, "", region1, "...");
3930 note_and_explain_region(cx, "...is not the same lifetime as ",
3933 terr_regions_no_overlap(region1, region2) => {
3934 note_and_explain_region(cx, "", region1, "...");
3935 note_and_explain_region(cx, "...does not overlap ",
3938 terr_regions_insufficiently_polymorphic(_, conc_region) => {
3939 note_and_explain_region(cx,
3940 "concrete lifetime that was found is ",
3943 terr_regions_overly_polymorphic(_, conc_region) => {
3944 note_and_explain_region(cx,
3945 "expected concrete lifetime is ",
3952 pub fn provided_source(cx: &ctxt, id: ast::DefId) -> Option<ast::DefId> {
3953 cx.provided_method_sources.borrow().find(&id).map(|x| *x)
3956 pub fn provided_trait_methods(cx: &ctxt, id: ast::DefId) -> Vec<Rc<Method>> {
3958 match cx.map.find(id.node) {
3959 Some(ast_map::NodeItem(item)) => {
3961 ItemTrait(_, _, _, ref ms) => {
3962 let (_, p) = ast_util::split_trait_methods(ms.as_slice());
3965 match impl_or_trait_item(
3967 ast_util::local_def(m.id)) {
3968 MethodTraitItem(m) => m,
3974 cx.sess.bug(format!("provided_trait_methods: `{}` is \
3981 cx.sess.bug(format!("provided_trait_methods: `{}` is not a \
3987 csearch::get_provided_trait_methods(cx, id)
3991 fn lookup_locally_or_in_crate_store<V:Clone>(
3994 map: &mut DefIdMap<V>,
3995 load_external: || -> V) -> V {
3997 * Helper for looking things up in the various maps
3998 * that are populated during typeck::collect (e.g.,
3999 * `cx.impl_or_trait_items`, `cx.tcache`, etc). All of these share
4000 * the pattern that if the id is local, it should have
4001 * been loaded into the map by the `typeck::collect` phase.
4002 * If the def-id is external, then we have to go consult
4003 * the crate loading code (and cache the result for the future).
4006 match map.find_copy(&def_id) {
4007 Some(v) => { return v; }
4011 if def_id.krate == ast::LOCAL_CRATE {
4012 fail!("No def'n found for {:?} in tcx.{}", def_id, descr);
4014 let v = load_external();
4015 map.insert(def_id, v.clone());
4019 pub fn trait_item(cx: &ctxt, trait_did: ast::DefId, idx: uint)
4020 -> ImplOrTraitItem {
4021 let method_def_id = ty::trait_item_def_ids(cx, trait_did).get(idx)
4023 impl_or_trait_item(cx, method_def_id)
4026 pub fn trait_items(cx: &ctxt, trait_did: ast::DefId)
4027 -> Rc<Vec<ImplOrTraitItem>> {
4028 let mut trait_items = cx.trait_items_cache.borrow_mut();
4029 match trait_items.find_copy(&trait_did) {
4030 Some(trait_items) => trait_items,
4032 let def_ids = ty::trait_item_def_ids(cx, trait_did);
4033 let items: Rc<Vec<ImplOrTraitItem>> =
4034 Rc::new(def_ids.iter()
4035 .map(|d| impl_or_trait_item(cx, d.def_id()))
4037 trait_items.insert(trait_did, items.clone());
4043 pub fn impl_or_trait_item(cx: &ctxt, id: ast::DefId) -> ImplOrTraitItem {
4044 lookup_locally_or_in_crate_store("impl_or_trait_items",
4046 &mut *cx.impl_or_trait_items
4049 csearch::get_impl_or_trait_item(cx, id)
4053 pub fn trait_item_def_ids(cx: &ctxt, id: ast::DefId)
4054 -> Rc<Vec<ImplOrTraitItemId>> {
4055 lookup_locally_or_in_crate_store("trait_item_def_ids",
4057 &mut *cx.trait_item_def_ids.borrow_mut(),
4059 Rc::new(csearch::get_trait_item_def_ids(&cx.sess.cstore, id))
4063 pub fn impl_trait_ref(cx: &ctxt, id: ast::DefId) -> Option<Rc<TraitRef>> {
4064 match cx.impl_trait_cache.borrow().find(&id) {
4065 Some(ret) => { return ret.clone(); }
4069 let ret = if id.krate == ast::LOCAL_CRATE {
4070 debug!("(impl_trait_ref) searching for trait impl {:?}", id);
4071 match cx.map.find(id.node) {
4072 Some(ast_map::NodeItem(item)) => {
4074 ast::ItemImpl(_, ref opt_trait, _, _) => {
4077 Some(ty::node_id_to_trait_ref(cx, t.ref_id))
4088 csearch::get_impl_trait(cx, id)
4091 cx.impl_trait_cache.borrow_mut().insert(id, ret.clone());
4095 pub fn trait_ref_to_def_id(tcx: &ctxt, tr: &ast::TraitRef) -> ast::DefId {
4096 let def = *tcx.def_map.borrow()
4098 .expect("no def-map entry for trait");
4102 pub fn try_add_builtin_trait(
4104 trait_def_id: ast::DefId,
4105 builtin_bounds: &mut EnumSet<BuiltinBound>)
4108 //! Checks whether `trait_ref` refers to one of the builtin
4109 //! traits, like `Send`, and adds the corresponding
4110 //! bound to the set `builtin_bounds` if so. Returns true if `trait_ref`
4111 //! is a builtin trait.
4113 match tcx.lang_items.to_builtin_kind(trait_def_id) {
4114 Some(bound) => { builtin_bounds.add(bound); true }
4119 pub fn ty_to_def_id(ty: t) -> Option<ast::DefId> {
4121 ty_trait(box TyTrait { def_id: id, .. }) |
4124 ty_unboxed_closure(id, _) => Some(id),
4131 pub struct VariantInfo {
4133 pub arg_names: Option<Vec<ast::Ident> >,
4135 pub name: ast::Ident,
4143 /// Creates a new VariantInfo from the corresponding ast representation.
4145 /// Does not do any caching of the value in the type context.
4146 pub fn from_ast_variant(cx: &ctxt,
4147 ast_variant: &ast::Variant,
4148 discriminant: Disr) -> VariantInfo {
4149 let ctor_ty = node_id_to_type(cx, ast_variant.node.id);
4151 match ast_variant.node.kind {
4152 ast::TupleVariantKind(ref args) => {
4153 let arg_tys = if args.len() > 0 {
4154 ty_fn_args(ctor_ty).iter().map(|a| *a).collect()
4159 return VariantInfo {
4163 name: ast_variant.node.name,
4164 id: ast_util::local_def(ast_variant.node.id),
4165 disr_val: discriminant,
4166 vis: ast_variant.node.vis
4169 ast::StructVariantKind(ref struct_def) => {
4171 let fields: &[StructField] = struct_def.fields.as_slice();
4173 assert!(fields.len() > 0);
4175 let arg_tys = ty_fn_args(ctor_ty).iter().map(|a| *a).collect();
4176 let arg_names = fields.iter().map(|field| {
4177 match field.node.kind {
4178 NamedField(ident, _) => ident,
4179 UnnamedField(..) => cx.sess.bug(
4180 "enum_variants: all fields in struct must have a name")
4184 return VariantInfo {
4186 arg_names: Some(arg_names),
4188 name: ast_variant.node.name,
4189 id: ast_util::local_def(ast_variant.node.id),
4190 disr_val: discriminant,
4191 vis: ast_variant.node.vis
4198 pub fn substd_enum_variants(cx: &ctxt,
4201 -> Vec<Rc<VariantInfo>> {
4202 enum_variants(cx, id).iter().map(|variant_info| {
4203 let substd_args = variant_info.args.iter()
4204 .map(|aty| aty.subst(cx, substs)).collect::<Vec<_>>();
4206 let substd_ctor_ty = variant_info.ctor_ty.subst(cx, substs);
4208 Rc::new(VariantInfo {
4210 ctor_ty: substd_ctor_ty,
4211 ..(**variant_info).clone()
4216 pub fn item_path_str(cx: &ctxt, id: ast::DefId) -> String {
4217 with_path(cx, id, |path| ast_map::path_to_string(path)).to_string()
4222 TraitDtor(DefId, bool)
4226 pub fn is_present(&self) -> bool {
4228 TraitDtor(..) => true,
4233 pub fn has_drop_flag(&self) -> bool {
4236 &TraitDtor(_, flag) => flag
4241 /* If struct_id names a struct with a dtor, return Some(the dtor's id).
4242 Otherwise return none. */
4243 pub fn ty_dtor(cx: &ctxt, struct_id: DefId) -> DtorKind {
4244 match cx.destructor_for_type.borrow().find(&struct_id) {
4245 Some(&method_def_id) => {
4246 let flag = !has_attr(cx, struct_id, "unsafe_no_drop_flag");
4248 TraitDtor(method_def_id, flag)
4254 pub fn has_dtor(cx: &ctxt, struct_id: DefId) -> bool {
4255 ty_dtor(cx, struct_id).is_present()
4258 pub fn with_path<T>(cx: &ctxt, id: ast::DefId, f: |ast_map::PathElems| -> T) -> T {
4259 if id.krate == ast::LOCAL_CRATE {
4260 cx.map.with_path(id.node, f)
4262 f(ast_map::Values(csearch::get_item_path(cx, id).iter()).chain(None))
4266 pub fn enum_is_univariant(cx: &ctxt, id: ast::DefId) -> bool {
4267 enum_variants(cx, id).len() == 1
4270 pub fn type_is_empty(cx: &ctxt, t: t) -> bool {
4271 match ty::get(t).sty {
4272 ty_enum(did, _) => (*enum_variants(cx, did)).is_empty(),
4277 pub fn enum_variants(cx: &ctxt, id: ast::DefId) -> Rc<Vec<Rc<VariantInfo>>> {
4278 match cx.enum_var_cache.borrow().find(&id) {
4279 Some(variants) => return variants.clone(),
4280 _ => { /* fallthrough */ }
4283 let result = if ast::LOCAL_CRATE != id.krate {
4284 Rc::new(csearch::get_enum_variants(cx, id))
4287 Although both this code and check_enum_variants in typeck/check
4288 call eval_const_expr, it should never get called twice for the same
4289 expr, since check_enum_variants also updates the enum_var_cache
4291 match cx.map.get(id.node) {
4292 ast_map::NodeItem(item) => {
4294 ast::ItemEnum(ref enum_definition, _) => {
4295 let mut last_discriminant: Option<Disr> = None;
4296 Rc::new(enum_definition.variants.iter().map(|&variant| {
4298 let mut discriminant = match last_discriminant {
4299 Some(val) => val + 1,
4300 None => INITIAL_DISCRIMINANT_VALUE
4303 match variant.node.disr_expr {
4304 Some(ref e) => match const_eval::eval_const_expr_partial(cx, &**e) {
4305 Ok(const_eval::const_int(val)) => {
4306 discriminant = val as Disr
4308 Ok(const_eval::const_uint(val)) => {
4309 discriminant = val as Disr
4314 "expected signed integer constant");
4319 format!("expected constant: {}",
4326 last_discriminant = Some(discriminant);
4327 Rc::new(VariantInfo::from_ast_variant(cx, &*variant,
4332 cx.sess.bug("enum_variants: id not bound to an enum")
4336 _ => cx.sess.bug("enum_variants: id not bound to an enum")
4340 cx.enum_var_cache.borrow_mut().insert(id, result.clone());
4345 // Returns information about the enum variant with the given ID:
4346 pub fn enum_variant_with_id(cx: &ctxt,
4347 enum_id: ast::DefId,
4348 variant_id: ast::DefId)
4349 -> Rc<VariantInfo> {
4350 enum_variants(cx, enum_id).iter()
4351 .find(|variant| variant.id == variant_id)
4352 .expect("enum_variant_with_id(): no variant exists with that ID")
4357 // If the given item is in an external crate, looks up its type and adds it to
4358 // the type cache. Returns the type parameters and type.
4359 pub fn lookup_item_type(cx: &ctxt,
4362 lookup_locally_or_in_crate_store(
4363 "tcache", did, &mut *cx.tcache.borrow_mut(),
4364 || csearch::get_type(cx, did))
4367 pub fn lookup_impl_vtables(cx: &ctxt,
4369 -> typeck::vtable_res {
4370 lookup_locally_or_in_crate_store(
4371 "impl_vtables", did, &mut *cx.impl_vtables.borrow_mut(),
4372 || csearch::get_impl_vtables(cx, did) )
4375 /// Given the did of a trait, returns its canonical trait ref.
4376 pub fn lookup_trait_def(cx: &ctxt, did: ast::DefId) -> Rc<ty::TraitDef> {
4377 let mut trait_defs = cx.trait_defs.borrow_mut();
4378 match trait_defs.find_copy(&did) {
4379 Some(trait_def) => {
4380 // The item is in this crate. The caller should have added it to the
4381 // type cache already
4385 assert!(did.krate != ast::LOCAL_CRATE);
4386 let trait_def = Rc::new(csearch::get_trait_def(cx, did));
4387 trait_defs.insert(did, trait_def.clone());
4393 /// Given a reference to a trait, returns the bounds declared on the
4394 /// trait, with appropriate substitutions applied.
4395 pub fn bounds_for_trait_ref(tcx: &ctxt,
4396 trait_ref: &TraitRef)
4399 let trait_def = lookup_trait_def(tcx, trait_ref.def_id);
4400 debug!("bounds_for_trait_ref(trait_def={}, trait_ref={})",
4401 trait_def.repr(tcx), trait_ref.repr(tcx));
4402 trait_def.bounds.subst(tcx, &trait_ref.substs)
4405 /// Iterate over attributes of a definition.
4406 // (This should really be an iterator, but that would require csearch and
4407 // decoder to use iterators instead of higher-order functions.)
4408 pub fn each_attr(tcx: &ctxt, did: DefId, f: |&ast::Attribute| -> bool) -> bool {
4410 let item = tcx.map.expect_item(did.node);
4411 item.attrs.iter().all(|attr| f(attr))
4413 info!("getting foreign attrs");
4414 let mut cont = true;
4415 csearch::get_item_attrs(&tcx.sess.cstore, did, |attrs| {
4417 cont = attrs.iter().all(|attr| f(attr));
4425 /// Determine whether an item is annotated with an attribute
4426 pub fn has_attr(tcx: &ctxt, did: DefId, attr: &str) -> bool {
4427 let mut found = false;
4428 each_attr(tcx, did, |item| {
4429 if item.check_name(attr) {
4439 /// Determine whether an item is annotated with `#[repr(packed)]`
4440 pub fn lookup_packed(tcx: &ctxt, did: DefId) -> bool {
4441 lookup_repr_hints(tcx, did).contains(&attr::ReprPacked)
4444 /// Determine whether an item is annotated with `#[simd]`
4445 pub fn lookup_simd(tcx: &ctxt, did: DefId) -> bool {
4446 has_attr(tcx, did, "simd")
4449 /// Obtain the representation annotation for a struct definition.
4450 pub fn lookup_repr_hints(tcx: &ctxt, did: DefId) -> Vec<attr::ReprAttr> {
4451 let mut acc = Vec::new();
4453 ty::each_attr(tcx, did, |meta| {
4454 acc.extend(attr::find_repr_attrs(tcx.sess.diagnostic(), meta).move_iter());
4461 // Look up a field ID, whether or not it's local
4462 // Takes a list of type substs in case the struct is generic
4463 pub fn lookup_field_type(tcx: &ctxt,
4468 let t = if id.krate == ast::LOCAL_CRATE {
4469 node_id_to_type(tcx, id.node)
4471 let mut tcache = tcx.tcache.borrow_mut();
4472 let pty = tcache.find_or_insert_with(id, |_| {
4473 csearch::get_field_type(tcx, struct_id, id)
4477 t.subst(tcx, substs)
4480 // Lookup all ancestor structs of a struct indicated by did. That is the reflexive,
4481 // transitive closure of doing a single lookup in cx.superstructs.
4482 fn each_super_struct(cx: &ctxt, mut did: ast::DefId, f: |ast::DefId|) {
4483 let superstructs = cx.superstructs.borrow();
4487 match superstructs.find(&did) {
4488 Some(&Some(def_id)) => {
4491 Some(&None) => break,
4494 format!("ID not mapped to super-struct: {}",
4495 cx.map.node_to_string(did.node)).as_slice());
4501 // Look up the list of field names and IDs for a given struct.
4502 // Fails if the id is not bound to a struct.
4503 pub fn lookup_struct_fields(cx: &ctxt, did: ast::DefId) -> Vec<field_ty> {
4504 if did.krate == ast::LOCAL_CRATE {
4505 // We store the fields which are syntactically in each struct in cx. So
4506 // we have to walk the inheritance chain of the struct to get all the
4507 // structs (explicit and inherited) for a struct. If this is expensive
4508 // we could cache the whole list of fields here.
4509 let struct_fields = cx.struct_fields.borrow();
4510 let mut results: SmallVector<&[field_ty]> = SmallVector::zero();
4511 each_super_struct(cx, did, |s| {
4512 match struct_fields.find(&s) {
4513 Some(fields) => results.push(fields.as_slice()),
4516 format!("ID not mapped to struct fields: {}",
4517 cx.map.node_to_string(did.node)).as_slice());
4522 let len = results.as_slice().iter().map(|x| x.len()).sum();
4523 let mut result: Vec<field_ty> = Vec::with_capacity(len);
4524 result.extend(results.as_slice().iter().flat_map(|rs| rs.iter().map(|f| f.clone())));
4525 assert!(result.len() == len);
4528 csearch::get_struct_fields(&cx.sess.cstore, did)
4532 pub fn is_tuple_struct(cx: &ctxt, did: ast::DefId) -> bool {
4533 let fields = lookup_struct_fields(cx, did);
4534 !fields.is_empty() && fields.iter().all(|f| f.name == token::special_names::unnamed_field)
4537 pub fn lookup_struct_field(cx: &ctxt,
4539 field_id: ast::DefId)
4541 let r = lookup_struct_fields(cx, parent);
4542 match r.iter().find(|f| f.id.node == field_id.node) {
4543 Some(t) => t.clone(),
4544 None => cx.sess.bug("struct ID not found in parent's fields")
4548 // Returns a list of fields corresponding to the struct's items. trans uses
4549 // this. Takes a list of substs with which to instantiate field types.
4550 pub fn struct_fields(cx: &ctxt, did: ast::DefId, substs: &Substs)
4552 lookup_struct_fields(cx, did).iter().map(|f| {
4554 // FIXME #6993: change type of field to Name and get rid of new()
4555 ident: ast::Ident::new(f.name),
4557 ty: lookup_field_type(cx, did, f.id, substs),
4564 // Returns a list of fields corresponding to the tuple's items. trans uses
4566 pub fn tup_fields(v: &[t]) -> Vec<field> {
4567 v.iter().enumerate().map(|(i, &f)| {
4569 // FIXME #6993: change type of field to Name and get rid of new()
4570 ident: ast::Ident::new(token::intern(i.to_string().as_slice())),
4579 pub struct UnboxedClosureUpvar {
4585 // Returns a list of `UnboxedClosureUpvar`s for each upvar.
4586 pub fn unboxed_closure_upvars(tcx: &ctxt, closure_id: ast::DefId)
4587 -> Vec<UnboxedClosureUpvar> {
4588 if closure_id.krate == ast::LOCAL_CRATE {
4589 match tcx.freevars.borrow().find(&closure_id.node) {
4590 None => tcx.sess.bug("no freevars for unboxed closure?!"),
4591 Some(ref freevars) => {
4592 freevars.iter().map(|freevar| {
4593 let freevar_def_id = freevar.def.def_id();
4594 UnboxedClosureUpvar {
4597 ty: node_id_to_type(tcx, freevar_def_id.node),
4603 tcx.sess.bug("unimplemented cross-crate closure upvars")
4607 pub fn is_binopable(cx: &ctxt, ty: t, op: ast::BinOp) -> bool {
4608 static tycat_other: int = 0;
4609 static tycat_bool: int = 1;
4610 static tycat_char: int = 2;
4611 static tycat_int: int = 3;
4612 static tycat_float: int = 4;
4613 static tycat_bot: int = 5;
4614 static tycat_raw_ptr: int = 6;
4616 static opcat_add: int = 0;
4617 static opcat_sub: int = 1;
4618 static opcat_mult: int = 2;
4619 static opcat_shift: int = 3;
4620 static opcat_rel: int = 4;
4621 static opcat_eq: int = 5;
4622 static opcat_bit: int = 6;
4623 static opcat_logic: int = 7;
4624 static opcat_mod: int = 8;
4626 fn opcat(op: ast::BinOp) -> int {
4628 ast::BiAdd => opcat_add,
4629 ast::BiSub => opcat_sub,
4630 ast::BiMul => opcat_mult,
4631 ast::BiDiv => opcat_mult,
4632 ast::BiRem => opcat_mod,
4633 ast::BiAnd => opcat_logic,
4634 ast::BiOr => opcat_logic,
4635 ast::BiBitXor => opcat_bit,
4636 ast::BiBitAnd => opcat_bit,
4637 ast::BiBitOr => opcat_bit,
4638 ast::BiShl => opcat_shift,
4639 ast::BiShr => opcat_shift,
4640 ast::BiEq => opcat_eq,
4641 ast::BiNe => opcat_eq,
4642 ast::BiLt => opcat_rel,
4643 ast::BiLe => opcat_rel,
4644 ast::BiGe => opcat_rel,
4645 ast::BiGt => opcat_rel
4649 fn tycat(cx: &ctxt, ty: t) -> int {
4650 if type_is_simd(cx, ty) {
4651 return tycat(cx, simd_type(cx, ty))
4654 ty_char => tycat_char,
4655 ty_bool => tycat_bool,
4656 ty_int(_) | ty_uint(_) | ty_infer(IntVar(_)) => tycat_int,
4657 ty_float(_) | ty_infer(FloatVar(_)) => tycat_float,
4658 ty_bot => tycat_bot,
4659 ty_ptr(_) => tycat_raw_ptr,
4664 static t: bool = true;
4665 static f: bool = false;
4668 // +, -, *, shift, rel, ==, bit, logic, mod
4669 /*other*/ [f, f, f, f, f, f, f, f, f],
4670 /*bool*/ [f, f, f, f, t, t, t, t, f],
4671 /*char*/ [f, f, f, f, t, t, f, f, f],
4672 /*int*/ [t, t, t, t, t, t, t, f, t],
4673 /*float*/ [t, t, t, f, t, t, f, f, f],
4674 /*bot*/ [t, t, t, t, t, t, t, t, t],
4675 /*raw ptr*/ [f, f, f, f, t, t, f, f, f]];
4677 return tbl[tycat(cx, ty) as uint ][opcat(op) as uint];
4680 /// Returns an equivalent type with all the typedefs and self regions removed.
4681 pub fn normalize_ty(cx: &ctxt, t: t) -> t {
4682 let u = TypeNormalizer(cx).fold_ty(t);
4685 struct TypeNormalizer<'a, 'tcx: 'a>(&'a ctxt<'tcx>);
4687 impl<'a, 'tcx> TypeFolder<'tcx> for TypeNormalizer<'a, 'tcx> {
4688 fn tcx<'a>(&'a self) -> &'a ctxt<'tcx> { let TypeNormalizer(c) = *self; c }
4690 fn fold_ty(&mut self, t: ty::t) -> ty::t {
4691 match self.tcx().normalized_cache.borrow().find_copy(&t) {
4696 let t_norm = ty_fold::super_fold_ty(self, t);
4697 self.tcx().normalized_cache.borrow_mut().insert(t, t_norm);
4701 fn fold_region(&mut self, _: ty::Region) -> ty::Region {
4705 fn fold_substs(&mut self,
4706 substs: &subst::Substs)
4708 subst::Substs { regions: subst::ErasedRegions,
4709 types: substs.types.fold_with(self) }
4712 fn fold_sig(&mut self,
4715 // The binder-id is only relevant to bound regions, which
4716 // are erased at trans time.
4718 binder_id: ast::DUMMY_NODE_ID,
4719 inputs: sig.inputs.fold_with(self),
4720 output: sig.output.fold_with(self),
4721 variadic: sig.variadic,
4727 // Returns the repeat count for a repeating vector expression.
4728 pub fn eval_repeat_count(tcx: &ctxt, count_expr: &ast::Expr) -> uint {
4729 match const_eval::eval_const_expr_partial(tcx, count_expr) {
4730 Ok(ref const_val) => match *const_val {
4731 const_eval::const_int(count) => if count < 0 {
4732 tcx.sess.span_err(count_expr.span,
4733 "expected positive integer for \
4734 repeat count, found negative integer");
4739 const_eval::const_uint(count) => count as uint,
4740 const_eval::const_float(count) => {
4741 tcx.sess.span_err(count_expr.span,
4742 "expected positive integer for \
4743 repeat count, found float");
4746 const_eval::const_str(_) => {
4747 tcx.sess.span_err(count_expr.span,
4748 "expected positive integer for \
4749 repeat count, found string");
4752 const_eval::const_bool(_) => {
4753 tcx.sess.span_err(count_expr.span,
4754 "expected positive integer for \
4755 repeat count, found boolean");
4758 const_eval::const_binary(_) => {
4759 tcx.sess.span_err(count_expr.span,
4760 "expected positive integer for \
4761 repeat count, found binary array");
4764 const_eval::const_nil => {
4765 tcx.sess.span_err(count_expr.span,
4766 "expected positive integer for \
4767 repeat count, found ()");
4772 tcx.sess.span_err(count_expr.span,
4773 "expected constant integer for repeat count, \
4780 // Iterate over a type parameter's bounded traits and any supertraits
4781 // of those traits, ignoring kinds.
4782 // Here, the supertraits are the transitive closure of the supertrait
4783 // relation on the supertraits from each bounded trait's constraint
4785 pub fn each_bound_trait_and_supertraits(tcx: &ctxt,
4786 bounds: &[Rc<TraitRef>],
4787 f: |Rc<TraitRef>| -> bool)
4789 for bound_trait_ref in bounds.iter() {
4790 let mut supertrait_set = HashMap::new();
4791 let mut trait_refs = Vec::new();
4794 // Seed the worklist with the trait from the bound
4795 supertrait_set.insert(bound_trait_ref.def_id, ());
4796 trait_refs.push(bound_trait_ref.clone());
4798 // Add the given trait ty to the hash map
4799 while i < trait_refs.len() {
4800 debug!("each_bound_trait_and_supertraits(i={:?}, trait_ref={})",
4801 i, trait_refs.get(i).repr(tcx));
4803 if !f(trait_refs.get(i).clone()) {
4807 // Add supertraits to supertrait_set
4808 let trait_ref = trait_refs.get(i).clone();
4809 let trait_def = lookup_trait_def(tcx, trait_ref.def_id);
4810 for supertrait_ref in trait_def.bounds.trait_bounds.iter() {
4811 let supertrait_ref = supertrait_ref.subst(tcx, &trait_ref.substs);
4812 debug!("each_bound_trait_and_supertraits(supertrait_ref={})",
4813 supertrait_ref.repr(tcx));
4815 let d_id = supertrait_ref.def_id;
4816 if !supertrait_set.contains_key(&d_id) {
4817 // FIXME(#5527) Could have same trait multiple times
4818 supertrait_set.insert(d_id, ());
4819 trait_refs.push(supertrait_ref.clone());
4829 pub fn required_region_bounds(tcx: &ctxt,
4830 region_bounds: &[ty::Region],
4831 builtin_bounds: BuiltinBounds,
4832 trait_bounds: &[Rc<TraitRef>])
4836 * Given a type which must meet the builtin bounds and trait
4837 * bounds, returns a set of lifetimes which the type must outlive.
4839 * Requires that trait definitions have been processed.
4842 let mut all_bounds = Vec::new();
4844 debug!("required_region_bounds(builtin_bounds={}, trait_bounds={})",
4845 builtin_bounds.repr(tcx),
4846 trait_bounds.repr(tcx));
4848 all_bounds.push_all(region_bounds);
4850 push_region_bounds([],
4854 debug!("from builtin bounds: all_bounds={}", all_bounds.repr(tcx));
4856 each_bound_trait_and_supertraits(
4860 let bounds = ty::bounds_for_trait_ref(tcx, &*trait_ref);
4861 push_region_bounds(bounds.opt_region_bound.as_slice(),
4862 bounds.builtin_bounds,
4864 debug!("from {}: bounds={} all_bounds={}",
4865 trait_ref.repr(tcx),
4867 all_bounds.repr(tcx));
4873 fn push_region_bounds(region_bounds: &[ty::Region],
4874 builtin_bounds: ty::BuiltinBounds,
4875 all_bounds: &mut Vec<ty::Region>) {
4876 all_bounds.push_all(region_bounds.as_slice());
4878 if builtin_bounds.contains_elem(ty::BoundSend) {
4879 all_bounds.push(ty::ReStatic);
4884 pub fn get_tydesc_ty(tcx: &ctxt) -> Result<t, String> {
4885 tcx.lang_items.require(TyDescStructLangItem).map(|tydesc_lang_item| {
4886 tcx.intrinsic_defs.borrow().find_copy(&tydesc_lang_item)
4887 .expect("Failed to resolve TyDesc")
4891 pub fn get_opaque_ty(tcx: &ctxt) -> Result<t, String> {
4892 tcx.lang_items.require(OpaqueStructLangItem).map(|opaque_lang_item| {
4893 tcx.intrinsic_defs.borrow().find_copy(&opaque_lang_item)
4894 .expect("Failed to resolve Opaque")
4898 pub fn visitor_object_ty(tcx: &ctxt,
4899 ptr_region: ty::Region,
4900 trait_region: ty::Region)
4901 -> Result<(Rc<TraitRef>, t), String>
4903 let trait_lang_item = match tcx.lang_items.require(TyVisitorTraitLangItem) {
4905 Err(s) => { return Err(s); }
4907 let substs = Substs::empty();
4908 let trait_ref = Rc::new(TraitRef { def_id: trait_lang_item, substs: substs });
4909 Ok((trait_ref.clone(),
4910 mk_rptr(tcx, ptr_region,
4911 mt {mutbl: ast::MutMutable,
4914 trait_ref.substs.clone(),
4915 ty::region_existential_bound(trait_region))})))
4918 pub fn item_variances(tcx: &ctxt, item_id: ast::DefId) -> Rc<ItemVariances> {
4919 lookup_locally_or_in_crate_store(
4920 "item_variance_map", item_id, &mut *tcx.item_variance_map.borrow_mut(),
4921 || Rc::new(csearch::get_item_variances(&tcx.sess.cstore, item_id)))
4924 /// Records a trait-to-implementation mapping.
4925 pub fn record_trait_implementation(tcx: &ctxt,
4926 trait_def_id: DefId,
4927 impl_def_id: DefId) {
4928 match tcx.trait_impls.borrow().find(&trait_def_id) {
4929 Some(impls_for_trait) => {
4930 impls_for_trait.borrow_mut().push(impl_def_id);
4935 tcx.trait_impls.borrow_mut().insert(trait_def_id, Rc::new(RefCell::new(vec!(impl_def_id))));
4938 /// Populates the type context with all the implementations for the given type
4940 pub fn populate_implementations_for_type_if_necessary(tcx: &ctxt,
4941 type_id: ast::DefId) {
4942 if type_id.krate == LOCAL_CRATE {
4945 if tcx.populated_external_types.borrow().contains(&type_id) {
4949 csearch::each_implementation_for_type(&tcx.sess.cstore, type_id,
4951 let impl_items = csearch::get_impl_items(&tcx.sess.cstore,
4954 // Record the trait->implementation mappings, if applicable.
4955 let associated_traits = csearch::get_impl_trait(tcx, impl_def_id);
4956 for trait_ref in associated_traits.iter() {
4957 record_trait_implementation(tcx, trait_ref.def_id, impl_def_id);
4960 // For any methods that use a default implementation, add them to
4961 // the map. This is a bit unfortunate.
4962 for impl_item_def_id in impl_items.iter() {
4963 let method_def_id = impl_item_def_id.def_id();
4964 match impl_or_trait_item(tcx, method_def_id) {
4965 MethodTraitItem(method) => {
4966 for &source in method.provided_source.iter() {
4967 tcx.provided_method_sources
4969 .insert(method_def_id, source);
4975 // Store the implementation info.
4976 tcx.impl_items.borrow_mut().insert(impl_def_id, impl_items);
4978 // If this is an inherent implementation, record it.
4979 if associated_traits.is_none() {
4980 match tcx.inherent_impls.borrow().find(&type_id) {
4981 Some(implementation_list) => {
4982 implementation_list.borrow_mut().push(impl_def_id);
4987 tcx.inherent_impls.borrow_mut().insert(type_id,
4988 Rc::new(RefCell::new(vec!(impl_def_id))));
4992 tcx.populated_external_types.borrow_mut().insert(type_id);
4995 /// Populates the type context with all the implementations for the given
4996 /// trait if necessary.
4997 pub fn populate_implementations_for_trait_if_necessary(
4999 trait_id: ast::DefId) {
5000 if trait_id.krate == LOCAL_CRATE {
5003 if tcx.populated_external_traits.borrow().contains(&trait_id) {
5007 csearch::each_implementation_for_trait(&tcx.sess.cstore, trait_id,
5008 |implementation_def_id| {
5009 let impl_items = csearch::get_impl_items(&tcx.sess.cstore, implementation_def_id);
5011 // Record the trait->implementation mapping.
5012 record_trait_implementation(tcx, trait_id, implementation_def_id);
5014 // For any methods that use a default implementation, add them to
5015 // the map. This is a bit unfortunate.
5016 for impl_item_def_id in impl_items.iter() {
5017 let method_def_id = impl_item_def_id.def_id();
5018 match impl_or_trait_item(tcx, method_def_id) {
5019 MethodTraitItem(method) => {
5020 for &source in method.provided_source.iter() {
5021 tcx.provided_method_sources
5023 .insert(method_def_id, source);
5029 // Store the implementation info.
5030 tcx.impl_items.borrow_mut().insert(implementation_def_id, impl_items);
5033 tcx.populated_external_traits.borrow_mut().insert(trait_id);
5036 /// Given the def_id of an impl, return the def_id of the trait it implements.
5037 /// If it implements no trait, return `None`.
5038 pub fn trait_id_of_impl(tcx: &ctxt,
5039 def_id: ast::DefId) -> Option<ast::DefId> {
5040 let node = match tcx.map.find(def_id.node) {
5045 ast_map::NodeItem(item) => {
5047 ast::ItemImpl(_, Some(ref trait_ref), _, _) => {
5048 Some(node_id_to_trait_ref(tcx, trait_ref.ref_id).def_id)
5057 /// If the given def ID describes a method belonging to an impl, return the
5058 /// ID of the impl that the method belongs to. Otherwise, return `None`.
5059 pub fn impl_of_method(tcx: &ctxt, def_id: ast::DefId)
5060 -> Option<ast::DefId> {
5061 if def_id.krate != LOCAL_CRATE {
5062 return match csearch::get_impl_or_trait_item(tcx,
5063 def_id).container() {
5064 TraitContainer(_) => None,
5065 ImplContainer(def_id) => Some(def_id),
5068 match tcx.impl_or_trait_items.borrow().find_copy(&def_id) {
5069 Some(trait_item) => {
5070 match trait_item.container() {
5071 TraitContainer(_) => None,
5072 ImplContainer(def_id) => Some(def_id),
5079 /// If the given def ID describes an item belonging to a trait (either a
5080 /// default method or an implementation of a trait method), return the ID of
5081 /// the trait that the method belongs to. Otherwise, return `None`.
5082 pub fn trait_of_item(tcx: &ctxt, def_id: ast::DefId) -> Option<ast::DefId> {
5083 if def_id.krate != LOCAL_CRATE {
5084 return csearch::get_trait_of_item(&tcx.sess.cstore, def_id, tcx);
5086 match tcx.impl_or_trait_items.borrow().find_copy(&def_id) {
5087 Some(impl_or_trait_item) => {
5088 match impl_or_trait_item.container() {
5089 TraitContainer(def_id) => Some(def_id),
5090 ImplContainer(def_id) => trait_id_of_impl(tcx, def_id),
5097 /// If the given def ID describes an item belonging to a trait, (either a
5098 /// default method or an implementation of a trait method), return the ID of
5099 /// the method inside trait definition (this means that if the given def ID
5100 /// is already that of the original trait method, then the return value is
5102 /// Otherwise, return `None`.
5103 pub fn trait_item_of_item(tcx: &ctxt, def_id: ast::DefId)
5104 -> Option<ImplOrTraitItemId> {
5105 let impl_item = match tcx.impl_or_trait_items.borrow().find(&def_id) {
5106 Some(m) => m.clone(),
5107 None => return None,
5109 let name = match impl_item {
5110 MethodTraitItem(method) => method.ident.name,
5112 match trait_of_item(tcx, def_id) {
5113 Some(trait_did) => {
5114 let trait_items = ty::trait_items(tcx, trait_did);
5116 .position(|m| m.ident().name == name)
5117 .map(|idx| ty::trait_item(tcx, trait_did, idx).id())
5123 /// Creates a hash of the type `t` which will be the same no matter what crate
5124 /// context it's calculated within. This is used by the `type_id` intrinsic.
5125 pub fn hash_crate_independent(tcx: &ctxt, t: t, svh: &Svh) -> u64 {
5126 let mut state = sip::SipState::new();
5127 macro_rules! byte( ($b:expr) => { ($b as u8).hash(&mut state) } );
5128 macro_rules! hash( ($e:expr) => { $e.hash(&mut state) } );
5130 let region = |_state: &mut sip::SipState, r: Region| {
5140 tcx.sess.bug("non-static region found when hashing a type")
5144 let did = |state: &mut sip::SipState, did: DefId| {
5145 let h = if ast_util::is_local(did) {
5148 tcx.sess.cstore.get_crate_hash(did.krate)
5150 h.as_str().hash(state);
5151 did.node.hash(state);
5153 let mt = |state: &mut sip::SipState, mt: mt| {
5154 mt.mutbl.hash(state);
5156 ty::walk_ty(t, |t| {
5157 match ty::get(t).sty {
5160 ty_bool => byte!(2),
5161 ty_char => byte!(3),
5187 ty_vec(_, Some(n)) => {
5191 ty_vec(_, None) => {
5193 0u8.hash(&mut state);
5201 region(&mut state, r);
5204 ty_bare_fn(ref b) => {
5209 ty_closure(ref c) => {
5215 UniqTraitStore => byte!(0),
5216 RegionTraitStore(r, m) => {
5218 region(&mut state, r);
5219 assert_eq!(m, ast::MutMutable);
5223 ty_trait(box ty::TyTrait { def_id: d, bounds, .. }) => {
5228 ty_struct(d, _) => {
5232 ty_tup(ref inner) => {
5239 did(&mut state, p.def_id);
5241 ty_open(_) => byte!(22),
5242 ty_infer(_) => unreachable!(),
5243 ty_err => byte!(23),
5244 ty_unboxed_closure(d, r) => {
5247 region(&mut state, r);
5256 pub fn to_string(self) -> &'static str {
5259 Contravariant => "-",
5266 pub fn construct_parameter_environment(
5268 generics: &ty::Generics,
5269 free_id: ast::NodeId)
5270 -> ParameterEnvironment
5272 /*! See `ParameterEnvironment` struct def'n for details */
5275 // Construct the free substs.
5279 let mut types = VecPerParamSpace::empty();
5280 for &space in subst::ParamSpace::all().iter() {
5281 push_types_from_defs(tcx, &mut types, space,
5282 generics.types.get_slice(space));
5285 // map bound 'a => free 'a
5286 let mut regions = VecPerParamSpace::empty();
5287 for &space in subst::ParamSpace::all().iter() {
5288 push_region_params(&mut regions, space, free_id,
5289 generics.regions.get_slice(space));
5292 let free_substs = Substs {
5294 regions: subst::NonerasedRegions(regions)
5298 // Compute the bounds on Self and the type parameters.
5301 let mut bounds = VecPerParamSpace::empty();
5302 for &space in subst::ParamSpace::all().iter() {
5303 push_bounds_from_defs(tcx, &mut bounds, space, &free_substs,
5304 generics.types.get_slice(space));
5308 // Compute region bounds. For now, these relations are stored in a
5309 // global table on the tcx, so just enter them there. I'm not
5310 // crazy about this scheme, but it's convenient, at least.
5313 for &space in subst::ParamSpace::all().iter() {
5314 record_region_bounds_from_defs(tcx, space, &free_substs,
5315 generics.regions.get_slice(space));
5319 debug!("construct_parameter_environment: free_id={} \
5323 free_substs.repr(tcx),
5326 return ty::ParameterEnvironment {
5327 free_substs: free_substs,
5329 implicit_region_bound: ty::ReScope(free_id),
5332 fn push_region_params(regions: &mut VecPerParamSpace<ty::Region>,
5333 space: subst::ParamSpace,
5334 free_id: ast::NodeId,
5335 region_params: &[RegionParameterDef])
5337 for r in region_params.iter() {
5338 regions.push(space, ty::free_region_from_def(free_id, r));
5342 fn push_types_from_defs(tcx: &ty::ctxt,
5343 types: &mut subst::VecPerParamSpace<ty::t>,
5344 space: subst::ParamSpace,
5345 defs: &[TypeParameterDef]) {
5346 for (i, def) in defs.iter().enumerate() {
5347 let ty = ty::mk_param(tcx, space, i, def.def_id);
5348 types.push(space, ty);
5352 fn push_bounds_from_defs(tcx: &ty::ctxt,
5353 bounds: &mut subst::VecPerParamSpace<ParamBounds>,
5354 space: subst::ParamSpace,
5355 free_substs: &subst::Substs,
5356 defs: &[TypeParameterDef]) {
5357 for def in defs.iter() {
5358 let b = def.bounds.subst(tcx, free_substs);
5359 bounds.push(space, b);
5363 fn record_region_bounds_from_defs(tcx: &ty::ctxt,
5364 space: subst::ParamSpace,
5365 free_substs: &subst::Substs,
5366 defs: &[RegionParameterDef]) {
5367 for (subst_region, def) in
5368 free_substs.regions().get_slice(space).iter().zip(
5371 // For each region parameter 'subst...
5372 let bounds = def.bounds.subst(tcx, free_substs);
5373 for bound_region in bounds.iter() {
5374 // Which is declared with a bound like 'subst:'bound...
5375 match (subst_region, bound_region) {
5376 (&ty::ReFree(subst_fr), &ty::ReFree(bound_fr)) => {
5377 // Record that 'subst outlives 'bound. Or, put
5378 // another way, 'bound <= 'subst.
5379 tcx.region_maps.relate_free_regions(bound_fr, subst_fr);
5382 // All named regions are instantiated with free regions.
5384 format!("push_region_bounds_from_defs: \
5385 non free region: {} / {}",
5386 subst_region.repr(tcx),
5387 bound_region.repr(tcx)).as_slice());
5396 pub fn from_mutbl(m: ast::Mutability) -> BorrowKind {
5398 ast::MutMutable => MutBorrow,
5399 ast::MutImmutable => ImmBorrow,
5403 pub fn to_user_str(&self) -> &'static str {
5405 MutBorrow => "mutable",
5406 ImmBorrow => "immutable",
5407 UniqueImmBorrow => "uniquely immutable",
5412 impl<'tcx> mc::Typer<'tcx> for ty::ctxt<'tcx> {
5413 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx> {
5417 fn node_ty(&self, id: ast::NodeId) -> mc::McResult<ty::t> {
5418 Ok(ty::node_id_to_type(self, id))
5421 fn node_method_ty(&self, method_call: typeck::MethodCall) -> Option<ty::t> {
5422 self.method_map.borrow().find(&method_call).map(|method| method.ty)
5425 fn adjustments<'a>(&'a self) -> &'a RefCell<NodeMap<ty::AutoAdjustment>> {
5429 fn is_method_call(&self, id: ast::NodeId) -> bool {
5430 self.method_map.borrow().contains_key(&typeck::MethodCall::expr(id))
5433 fn temporary_scope(&self, rvalue_id: ast::NodeId) -> Option<ast::NodeId> {
5434 self.region_maps.temporary_scope(rvalue_id)
5437 fn upvar_borrow(&self, upvar_id: ty::UpvarId) -> ty::UpvarBorrow {
5438 self.upvar_borrow_map.borrow().get_copy(&upvar_id)
5441 fn capture_mode(&self, closure_expr_id: ast::NodeId)
5442 -> freevars::CaptureMode {
5443 self.capture_modes.borrow().get_copy(&closure_expr_id)
5446 fn unboxed_closures<'a>(&'a self)
5447 -> &'a RefCell<DefIdMap<UnboxedClosure>> {
5448 &self.unboxed_closures
5452 /// The category of explicit self.
5453 #[deriving(Clone, Eq, PartialEq)]
5454 pub enum ExplicitSelfCategory {
5455 StaticExplicitSelfCategory,
5456 ByValueExplicitSelfCategory,
5457 ByReferenceExplicitSelfCategory(Region, ast::Mutability),
5458 ByBoxExplicitSelfCategory,
5461 /// Pushes all the lifetimes in the given type onto the given list. A
5462 /// "lifetime in a type" is a lifetime specified by a reference or a lifetime
5463 /// in a list of type substitutions. This does *not* traverse into nominal
5464 /// types, nor does it resolve fictitious types.
5465 pub fn accumulate_lifetimes_in_type(accumulator: &mut Vec<ty::Region>,
5467 walk_ty(typ, |typ| {
5468 match get(typ).sty {
5469 ty_rptr(region, _) => accumulator.push(region),
5470 ty_enum(_, ref substs) |
5471 ty_trait(box TyTrait {
5475 ty_struct(_, ref substs) => {
5476 match substs.regions {
5477 subst::ErasedRegions => {}
5478 subst::NonerasedRegions(ref regions) => {
5479 for region in regions.iter() {
5480 accumulator.push(*region)
5485 ty_closure(ref closure_ty) => {
5486 match closure_ty.store {
5487 RegionTraitStore(region, _) => accumulator.push(region),
5488 UniqTraitStore => {}
5491 ty_unboxed_closure(_, ref region) => accumulator.push(*region),