1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Do not remove on snapshot creation. Needed for bootstrap. (Issue #22364)
12 #![cfg_attr(stage0, feature(custom_attribute))]
13 #![crate_name = "rustc_resolve"]
14 #![unstable(feature = "rustc_private", issue = "27812")]
15 #![cfg_attr(stage0, staged_api)]
16 #![crate_type = "dylib"]
17 #![crate_type = "rlib"]
18 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
19 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
20 html_root_url = "https://doc.rust-lang.org/nightly/")]
22 #![feature(associated_consts)]
23 #![feature(borrow_state)]
24 #![feature(rustc_diagnostic_macros)]
25 #![feature(rustc_private)]
26 #![feature(staged_api)]
34 extern crate rustc_bitflags;
35 extern crate rustc_front;
39 use self::PatternBindingMode::*;
40 use self::Namespace::*;
41 use self::NamespaceResult::*;
42 use self::ResolveResult::*;
43 use self::FallbackSuggestion::*;
44 use self::TypeParameters::*;
46 use self::UseLexicalScopeFlag::*;
47 use self::ModulePrefixResult::*;
48 use self::AssocItemResolveResult::*;
49 use self::NameSearchType::*;
50 use self::BareIdentifierPatternResolution::*;
51 use self::ParentLink::*;
52 use self::FallbackChecks::*;
54 use rustc::front::map as hir_map;
55 use rustc::session::Session;
57 use rustc::metadata::csearch;
58 use rustc::metadata::decoder::{DefLike, DlDef};
59 use rustc::middle::def::*;
60 use rustc::middle::def_id::DefId;
61 use rustc::middle::pat_util::pat_bindings_hygienic;
62 use rustc::middle::privacy::*;
63 use rustc::middle::subst::{ParamSpace, FnSpace, TypeSpace};
64 use rustc::middle::ty::{Freevar, FreevarMap, TraitMap, GlobMap};
65 use rustc::util::nodemap::{NodeMap, DefIdSet, FnvHashMap};
66 use rustc::util::lev_distance::lev_distance;
69 use syntax::ast::{CRATE_NODE_ID, Ident, Name, NodeId, CrateNum, TyIs, TyI8, TyI16, TyI32, TyI64};
70 use syntax::ast::{TyUs, TyU8, TyU16, TyU32, TyU64, TyF64, TyF32};
71 use syntax::attr::AttrMetaMethods;
72 use syntax::ext::mtwt;
73 use syntax::parse::token::{self, special_names, special_idents};
75 use syntax::codemap::{self, Span, Pos};
77 use rustc_front::intravisit::{self, FnKind, Visitor};
79 use rustc_front::hir::{Arm, BindByRef, BindByValue, BindingMode, Block};
80 use rustc_front::hir::Crate;
81 use rustc_front::hir::{Expr, ExprAgain, ExprBreak, ExprField};
82 use rustc_front::hir::{ExprLoop, ExprWhile, ExprMethodCall};
83 use rustc_front::hir::{ExprPath, ExprStruct, FnDecl};
84 use rustc_front::hir::{ForeignItemFn, ForeignItemStatic, Generics};
85 use rustc_front::hir::{ImplItem, Item, ItemConst, ItemEnum, ItemExternCrate};
86 use rustc_front::hir::{ItemFn, ItemForeignMod, ItemImpl, ItemMod, ItemStatic, ItemDefaultImpl};
87 use rustc_front::hir::{ItemStruct, ItemTrait, ItemTy, ItemUse};
88 use rustc_front::hir::Local;
89 use rustc_front::hir::{Pat, PatEnum, PatIdent, PatLit, PatQPath};
90 use rustc_front::hir::{PatRange, PatStruct, Path, PrimTy};
91 use rustc_front::hir::{TraitRef, Ty, TyBool, TyChar, TyFloat, TyInt};
92 use rustc_front::hir::{TyRptr, TyStr, TyUint, TyPath, TyPtr};
93 use rustc_front::util::walk_pat;
95 use std::collections::{HashMap, HashSet};
96 use std::cell::{Cell, RefCell};
98 use std::mem::replace;
99 use std::rc::{Rc, Weak};
102 use resolve_imports::{Target, ImportDirective, ImportResolution};
103 use resolve_imports::Shadowable;
105 // NB: This module needs to be declared first so diagnostics are
106 // registered before they are used.
111 mod build_reduced_graph;
114 // Perform the callback, not walking deeper if the return is true
115 macro_rules! execute_callback {
116 ($node: expr, $walker: expr) => (
117 if let Some(ref callback) = $walker.callback {
118 if callback($node, &mut $walker.resolved) {
125 enum SuggestionType {
131 pub enum ResolutionError<'a> {
132 /// error E0401: can't use type parameters from outer function
133 TypeParametersFromOuterFunction,
134 /// error E0402: cannot use an outer type parameter in this context
135 OuterTypeParameterContext,
136 /// error E0403: the name is already used for a type parameter in this type parameter list
137 NameAlreadyUsedInTypeParameterList(Name),
138 /// error E0404: is not a trait
139 IsNotATrait(&'a str),
140 /// error E0405: use of undeclared trait name
141 UndeclaredTraitName(&'a str),
142 /// error E0406: undeclared associated type
143 UndeclaredAssociatedType,
144 /// error E0407: method is not a member of trait
145 MethodNotMemberOfTrait(Name, &'a str),
146 /// error E0437: type is not a member of trait
147 TypeNotMemberOfTrait(Name, &'a str),
148 /// error E0438: const is not a member of trait
149 ConstNotMemberOfTrait(Name, &'a str),
150 /// error E0408: variable `{}` from pattern #1 is not bound in pattern
151 VariableNotBoundInPattern(Name, usize),
152 /// error E0409: variable is bound with different mode in pattern #{} than in pattern #1
153 VariableBoundWithDifferentMode(Name, usize),
154 /// error E0410: variable from pattern is not bound in pattern #1
155 VariableNotBoundInParentPattern(Name, usize),
156 /// error E0411: use of `Self` outside of an impl or trait
157 SelfUsedOutsideImplOrTrait,
158 /// error E0412: use of undeclared
159 UseOfUndeclared(&'a str, &'a str),
160 /// error E0413: declaration shadows an enum variant or unit-like struct in scope
161 DeclarationShadowsEnumVariantOrUnitLikeStruct(Name),
162 /// error E0414: only irrefutable patterns allowed here
163 OnlyIrrefutablePatternsAllowedHere(DefId, Name),
164 /// error E0415: identifier is bound more than once in this parameter list
165 IdentifierBoundMoreThanOnceInParameterList(&'a str),
166 /// error E0416: identifier is bound more than once in the same pattern
167 IdentifierBoundMoreThanOnceInSamePattern(&'a str),
168 /// error E0417: static variables cannot be referenced in a pattern
169 StaticVariableReference,
170 /// error E0418: is not an enum variant, struct or const
171 NotAnEnumVariantStructOrConst(&'a str),
172 /// error E0419: unresolved enum variant, struct or const
173 UnresolvedEnumVariantStructOrConst(&'a str),
174 /// error E0420: is not an associated const
175 NotAnAssociatedConst(&'a str),
176 /// error E0421: unresolved associated const
177 UnresolvedAssociatedConst(&'a str),
178 /// error E0422: does not name a struct
179 DoesNotNameAStruct(&'a str),
180 /// error E0423: is a struct variant name, but this expression uses it like a function name
181 StructVariantUsedAsFunction(&'a str),
182 /// error E0424: `self` is not available in a static method
183 SelfNotAvailableInStaticMethod,
184 /// error E0425: unresolved name
185 UnresolvedName(&'a str, &'a str),
186 /// error E0426: use of undeclared label
187 UndeclaredLabel(&'a str),
188 /// error E0427: cannot use `ref` binding mode with ...
189 CannotUseRefBindingModeWith(&'a str),
190 /// error E0428: duplicate definition
191 DuplicateDefinition(&'a str, Name),
192 /// error E0429: `self` imports are only allowed within a { } list
193 SelfImportsOnlyAllowedWithin,
194 /// error E0430: `self` import can only appear once in the list
195 SelfImportCanOnlyAppearOnceInTheList,
196 /// error E0431: `self` import can only appear in an import list with a non-empty prefix
197 SelfImportOnlyInImportListWithNonEmptyPrefix,
198 /// error E0432: unresolved import
199 UnresolvedImport(Option<(&'a str, &'a str)>),
200 /// error E0433: failed to resolve
201 FailedToResolve(&'a str),
202 /// error E0434: can't capture dynamic environment in a fn item
203 CannotCaptureDynamicEnvironmentInFnItem,
204 /// error E0435: attempt to use a non-constant value in a constant
205 AttemptToUseNonConstantValueInConstant,
208 fn resolve_error<'b, 'a: 'b, 'tcx: 'a>(resolver: &'b Resolver<'a, 'tcx>,
209 span: syntax::codemap::Span,
210 resolution_error: ResolutionError<'b>) {
211 if !resolver.emit_errors {
214 match resolution_error {
215 ResolutionError::TypeParametersFromOuterFunction => {
216 span_err!(resolver.session,
219 "can't use type parameters from outer function; try using a local type \
222 ResolutionError::OuterTypeParameterContext => {
223 span_err!(resolver.session,
226 "cannot use an outer type parameter in this context");
228 ResolutionError::NameAlreadyUsedInTypeParameterList(name) => {
229 span_err!(resolver.session,
232 "the name `{}` is already used for a type parameter in this type parameter \
236 ResolutionError::IsNotATrait(name) => {
237 span_err!(resolver.session, span, E0404, "`{}` is not a trait", name);
239 ResolutionError::UndeclaredTraitName(name) => {
240 span_err!(resolver.session,
243 "use of undeclared trait name `{}`",
246 ResolutionError::UndeclaredAssociatedType => {
247 span_err!(resolver.session, span, E0406, "undeclared associated type");
249 ResolutionError::MethodNotMemberOfTrait(method, trait_) => {
250 span_err!(resolver.session,
253 "method `{}` is not a member of trait `{}`",
257 ResolutionError::TypeNotMemberOfTrait(type_, trait_) => {
258 span_err!(resolver.session,
261 "type `{}` is not a member of trait `{}`",
265 ResolutionError::ConstNotMemberOfTrait(const_, trait_) => {
266 span_err!(resolver.session,
269 "const `{}` is not a member of trait `{}`",
273 ResolutionError::VariableNotBoundInPattern(variable_name, pattern_number) => {
274 span_err!(resolver.session,
277 "variable `{}` from pattern #1 is not bound in pattern #{}",
281 ResolutionError::VariableBoundWithDifferentMode(variable_name, pattern_number) => {
282 span_err!(resolver.session,
285 "variable `{}` is bound with different mode in pattern #{} than in pattern \
290 ResolutionError::VariableNotBoundInParentPattern(variable_name, pattern_number) => {
291 span_err!(resolver.session,
294 "variable `{}` from pattern #{} is not bound in pattern #1",
298 ResolutionError::SelfUsedOutsideImplOrTrait => {
299 span_err!(resolver.session,
302 "use of `Self` outside of an impl or trait");
304 ResolutionError::UseOfUndeclared(kind, name) => {
305 span_err!(resolver.session,
308 "use of undeclared {} `{}`",
312 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(name) => {
313 span_err!(resolver.session,
316 "declaration of `{}` shadows an enum variant or unit-like struct in scope",
319 ResolutionError::OnlyIrrefutablePatternsAllowedHere(did, name) => {
320 span_err!(resolver.session,
323 "only irrefutable patterns allowed here");
324 resolver.session.span_note(span,
325 "there already is a constant in scope sharing the same \
326 name as this pattern");
327 if let Some(sp) = resolver.ast_map.span_if_local(did) {
328 resolver.session.span_note(sp, "constant defined here");
330 if let Some(directive) = resolver.current_module
334 let item = resolver.ast_map.expect_item(directive.value_id);
335 resolver.session.span_note(item.span, "constant imported here");
338 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(identifier) => {
339 span_err!(resolver.session,
342 "identifier `{}` is bound more than once in this parameter list",
345 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(identifier) => {
346 span_err!(resolver.session,
349 "identifier `{}` is bound more than once in the same pattern",
352 ResolutionError::StaticVariableReference => {
353 span_err!(resolver.session,
356 "static variables cannot be referenced in a pattern, use a `const` instead");
358 ResolutionError::NotAnEnumVariantStructOrConst(name) => {
359 span_err!(resolver.session,
362 "`{}` is not an enum variant, struct or const",
365 ResolutionError::UnresolvedEnumVariantStructOrConst(name) => {
366 span_err!(resolver.session,
369 "unresolved enum variant, struct or const `{}`",
372 ResolutionError::NotAnAssociatedConst(name) => {
373 span_err!(resolver.session,
376 "`{}` is not an associated const",
379 ResolutionError::UnresolvedAssociatedConst(name) => {
380 span_err!(resolver.session,
383 "unresolved associated const `{}`",
386 ResolutionError::DoesNotNameAStruct(name) => {
387 span_err!(resolver.session,
390 "`{}` does not name a structure",
393 ResolutionError::StructVariantUsedAsFunction(path_name) => {
394 span_err!(resolver.session,
397 "`{}` is the name of a struct or struct variant, but this expression uses \
398 it like a function name",
401 ResolutionError::SelfNotAvailableInStaticMethod => {
402 span_err!(resolver.session,
405 "`self` is not available in a static method. Maybe a `self` argument is \
408 ResolutionError::UnresolvedName(path, name) => {
409 span_err!(resolver.session,
412 "unresolved name `{}`{}",
416 ResolutionError::UndeclaredLabel(name) => {
417 span_err!(resolver.session,
420 "use of undeclared label `{}`",
423 ResolutionError::CannotUseRefBindingModeWith(descr) => {
424 span_err!(resolver.session,
427 "cannot use `ref` binding mode with {}",
430 ResolutionError::DuplicateDefinition(namespace, name) => {
431 span_err!(resolver.session,
434 "duplicate definition of {} `{}`",
438 ResolutionError::SelfImportsOnlyAllowedWithin => {
439 span_err!(resolver.session,
443 "`self` imports are only allowed within a { } list");
445 ResolutionError::SelfImportCanOnlyAppearOnceInTheList => {
446 span_err!(resolver.session,
449 "`self` import can only appear once in the list");
451 ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix => {
452 span_err!(resolver.session,
455 "`self` import can only appear in an import list with a non-empty prefix");
457 ResolutionError::UnresolvedImport(name) => {
458 let msg = match name {
459 Some((n, p)) => format!("unresolved import `{}`{}", n, p),
460 None => "unresolved import".to_owned(),
462 span_err!(resolver.session, span, E0432, "{}", msg);
464 ResolutionError::FailedToResolve(msg) => {
465 span_err!(resolver.session, span, E0433, "failed to resolve. {}", msg);
467 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem => {
468 span_err!(resolver.session,
472 "can't capture dynamic environment in a fn item; use the || { ... } \
473 closure form instead");
475 ResolutionError::AttemptToUseNonConstantValueInConstant => {
476 span_err!(resolver.session,
479 "attempt to use a non-constant value in a constant");
484 #[derive(Copy, Clone)]
487 binding_mode: BindingMode,
490 // Map from the name in a pattern to its binding mode.
491 type BindingMap = HashMap<Name, BindingInfo>;
493 #[derive(Copy, Clone, PartialEq)]
494 enum PatternBindingMode {
496 LocalIrrefutableMode,
497 ArgumentIrrefutableMode,
500 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
506 /// A NamespaceResult represents the result of resolving an import in
507 /// a particular namespace. The result is either definitely-resolved,
508 /// definitely- unresolved, or unknown.
510 enum NamespaceResult {
511 /// Means that resolve hasn't gathered enough information yet to determine
512 /// whether the name is bound in this namespace. (That is, it hasn't
513 /// resolved all `use` directives yet.)
515 /// Means that resolve has determined that the name is definitely
516 /// not bound in the namespace.
518 /// Means that resolve has determined that the name is bound in the Module
519 /// argument, and specified by the NameBinding argument.
520 BoundResult(Rc<Module>, NameBinding),
523 impl NamespaceResult {
524 fn is_unknown(&self) -> bool {
526 UnknownResult => true,
530 fn is_unbound(&self) -> bool {
532 UnboundResult => true,
538 impl<'a, 'v, 'tcx> Visitor<'v> for Resolver<'a, 'tcx> {
539 fn visit_nested_item(&mut self, item: hir::ItemId) {
540 self.visit_item(self.ast_map.expect_item(item.id))
542 fn visit_item(&mut self, item: &Item) {
543 execute_callback!(hir_map::Node::NodeItem(item), self);
544 self.resolve_item(item);
546 fn visit_arm(&mut self, arm: &Arm) {
547 self.resolve_arm(arm);
549 fn visit_block(&mut self, block: &Block) {
550 execute_callback!(hir_map::Node::NodeBlock(block), self);
551 self.resolve_block(block);
553 fn visit_expr(&mut self, expr: &Expr) {
554 execute_callback!(hir_map::Node::NodeExpr(expr), self);
555 self.resolve_expr(expr);
557 fn visit_local(&mut self, local: &Local) {
558 execute_callback!(hir_map::Node::NodeLocal(&*local.pat), self);
559 self.resolve_local(local);
561 fn visit_ty(&mut self, ty: &Ty) {
562 self.resolve_type(ty);
564 fn visit_generics(&mut self, generics: &Generics) {
565 self.resolve_generics(generics);
567 fn visit_poly_trait_ref(&mut self, tref: &hir::PolyTraitRef, m: &hir::TraitBoundModifier) {
568 match self.resolve_trait_reference(tref.trait_ref.ref_id, &tref.trait_ref.path, 0) {
569 Ok(def) => self.record_def(tref.trait_ref.ref_id, def),
571 // error already reported
574 intravisit::walk_poly_trait_ref(self, tref, m);
576 fn visit_variant(&mut self,
577 variant: &hir::Variant,
579 item_id: ast::NodeId) {
580 execute_callback!(hir_map::Node::NodeVariant(variant), self);
581 if let Some(ref dis_expr) = variant.node.disr_expr {
582 // resolve the discriminator expr as a constant
583 self.with_constant_rib(|this| {
584 this.visit_expr(dis_expr);
588 // `intravisit::walk_variant` without the discriminant expression.
589 self.visit_variant_data(&variant.node.data,
595 fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem) {
596 execute_callback!(hir_map::Node::NodeForeignItem(foreign_item), self);
597 let type_parameters = match foreign_item.node {
598 ForeignItemFn(_, ref generics) => {
599 HasTypeParameters(generics, FnSpace, ItemRibKind)
601 ForeignItemStatic(..) => NoTypeParameters,
603 self.with_type_parameter_rib(type_parameters, |this| {
604 intravisit::walk_foreign_item(this, foreign_item);
607 fn visit_fn(&mut self,
608 function_kind: FnKind<'v>,
609 declaration: &'v FnDecl,
613 let rib_kind = match function_kind {
614 FnKind::ItemFn(_, generics, _, _, _, _) => {
615 self.visit_generics(generics);
618 FnKind::Method(_, sig, _) => {
619 self.visit_generics(&sig.generics);
620 self.visit_explicit_self(&sig.explicit_self);
623 FnKind::Closure(..) => ClosureRibKind(node_id),
625 self.resolve_function(rib_kind, declaration, block);
629 type ErrorMessage = Option<(Span, String)>;
631 enum ResolveResult<T> {
632 Failed(ErrorMessage), // Failed to resolve the name, optional helpful error message.
633 Indeterminate, // Couldn't determine due to unresolved globs.
634 Success(T), // Successfully resolved the import.
637 impl<T> ResolveResult<T> {
638 fn success(&self) -> bool {
646 enum FallbackSuggestion {
651 StaticMethod(String),
655 #[derive(Copy, Clone)]
656 enum TypeParameters<'a> {
658 HasTypeParameters(// Type parameters.
661 // Identifies the things that these parameters
662 // were declared on (type, fn, etc)
665 // The kind of the rib used for type parameters.
669 // The rib kind controls the translation of local
670 // definitions (`DefLocal`) to upvars (`DefUpvar`).
671 #[derive(Copy, Clone, Debug)]
673 // No translation needs to be applied.
676 // We passed through a closure scope at the given node ID.
677 // Translate upvars as appropriate.
678 ClosureRibKind(NodeId /* func id */),
680 // We passed through an impl or trait and are now in one of its
681 // methods. Allow references to ty params that impl or trait
682 // binds. Disallow any other upvars (including other ty params that are
686 // We passed through an item scope. Disallow upvars.
689 // We're in a constant item. Can't refer to dynamic stuff.
693 #[derive(Copy, Clone)]
694 enum UseLexicalScopeFlag {
699 enum ModulePrefixResult {
701 PrefixFound(Rc<Module>, usize),
704 #[derive(Copy, Clone)]
705 enum AssocItemResolveResult {
706 /// Syntax such as `<T>::item`, which can't be resolved until type
709 /// We should have been able to resolve the associated item.
710 ResolveAttempt(Option<PathResolution>),
713 #[derive(Copy, Clone, PartialEq)]
714 enum NameSearchType {
715 /// We're doing a name search in order to resolve a `use` directive.
718 /// We're doing a name search in order to resolve a path type, a path
719 /// expression, or a path pattern.
723 #[derive(Copy, Clone)]
724 enum BareIdentifierPatternResolution {
725 FoundStructOrEnumVariant(Def, LastPrivate),
726 FoundConst(Def, LastPrivate, Name),
727 BareIdentifierPatternUnresolved,
733 bindings: HashMap<Name, DefLike>,
738 fn new(kind: RibKind) -> Rib {
740 bindings: HashMap::new(),
746 /// A definition along with the index of the rib it was found on
748 ribs: Option<(Namespace, usize)>,
753 fn from_def(def: Def) -> Self {
761 /// The link from a module up to its nearest parent node.
762 #[derive(Clone,Debug)]
765 ModuleParentLink(Weak<Module>, Name),
766 BlockParentLink(Weak<Module>, NodeId),
769 /// One node in the tree of modules.
771 parent_link: ParentLink,
772 def: Cell<Option<Def>>,
775 children: RefCell<HashMap<Name, NameBindings>>,
776 imports: RefCell<Vec<ImportDirective>>,
778 // The external module children of this node that were declared with
780 external_module_children: RefCell<HashMap<Name, Rc<Module>>>,
782 // The anonymous children of this node. Anonymous children are pseudo-
783 // modules that are implicitly created around items contained within
786 // For example, if we have this:
794 // There will be an anonymous module created around `g` with the ID of the
795 // entry block for `f`.
796 anonymous_children: RefCell<NodeMap<Rc<Module>>>,
798 // The status of resolving each import in this module.
799 import_resolutions: RefCell<HashMap<Name, ImportResolution>>,
801 // The number of unresolved globs that this module exports.
802 glob_count: Cell<usize>,
804 // The number of unresolved pub imports (both regular and globs) in this module
805 pub_count: Cell<usize>,
807 // The number of unresolved pub glob imports in this module
808 pub_glob_count: Cell<usize>,
810 // The index of the import we're resolving.
811 resolved_import_count: Cell<usize>,
813 // Whether this module is populated. If not populated, any attempt to
814 // access the children must be preceded with a
815 // `populate_module_if_necessary` call.
816 populated: Cell<bool>,
820 fn new(parent_link: ParentLink,
826 parent_link: parent_link,
828 is_public: is_public,
829 children: RefCell::new(HashMap::new()),
830 imports: RefCell::new(Vec::new()),
831 external_module_children: RefCell::new(HashMap::new()),
832 anonymous_children: RefCell::new(NodeMap()),
833 import_resolutions: RefCell::new(HashMap::new()),
834 glob_count: Cell::new(0),
835 pub_count: Cell::new(0),
836 pub_glob_count: Cell::new(0),
837 resolved_import_count: Cell::new(0),
838 populated: Cell::new(!external),
842 fn def_id(&self) -> Option<DefId> {
843 self.def.get().as_ref().map(Def::def_id)
846 fn is_normal(&self) -> bool {
847 match self.def.get() {
848 Some(DefMod(_)) | Some(DefForeignMod(_)) => true,
853 fn is_trait(&self) -> bool {
854 match self.def.get() {
855 Some(DefTrait(_)) => true,
860 fn all_imports_resolved(&self) -> bool {
861 if self.imports.borrow_state() == ::std::cell::BorrowState::Writing {
862 // it is currently being resolved ! so nope
865 self.imports.borrow().len() == self.resolved_import_count.get()
871 pub fn inc_glob_count(&self) {
872 self.glob_count.set(self.glob_count.get() + 1);
874 pub fn dec_glob_count(&self) {
875 assert!(self.glob_count.get() > 0);
876 self.glob_count.set(self.glob_count.get() - 1);
878 pub fn inc_pub_count(&self) {
879 self.pub_count.set(self.pub_count.get() + 1);
881 pub fn dec_pub_count(&self) {
882 assert!(self.pub_count.get() > 0);
883 self.pub_count.set(self.pub_count.get() - 1);
885 pub fn inc_pub_glob_count(&self) {
886 self.pub_glob_count.set(self.pub_glob_count.get() + 1);
888 pub fn dec_pub_glob_count(&self) {
889 assert!(self.pub_glob_count.get() > 0);
890 self.pub_glob_count.set(self.pub_glob_count.get() - 1);
894 impl fmt::Debug for Module {
895 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
909 flags DefModifiers: u8 {
910 const PUBLIC = 1 << 0,
911 const IMPORTABLE = 1 << 1,
915 // Records a possibly-private value, type, or module definition.
918 modifiers: DefModifiers, // see note in ImportResolution about how to use this
919 def_or_module: DefOrModule,
930 fn create_from_module(module: Rc<Module>, span: Option<Span>) -> Self {
931 let modifiers = if module.is_public {
934 DefModifiers::empty()
935 } | DefModifiers::IMPORTABLE;
937 NsDef { modifiers: modifiers, def_or_module: DefOrModule::Module(module), span: span }
940 fn create_from_def(def: Def, modifiers: DefModifiers, span: Option<Span>) -> Self {
941 NsDef { modifiers: modifiers, def_or_module: DefOrModule::Def(def), span: span }
944 fn module(&self) -> Option<Rc<Module>> {
945 match self.def_or_module {
946 DefOrModule::Module(ref module) => Some(module.clone()),
947 DefOrModule::Def(_) => None,
951 fn def(&self) -> Option<Def> {
952 match self.def_or_module {
953 DefOrModule::Def(def) => Some(def),
954 DefOrModule::Module(ref module) => module.def.get(),
959 // Records at most one definition that a name in a namespace is bound to
960 #[derive(Clone,Debug)]
961 pub struct NameBinding(Rc<RefCell<Option<NsDef>>>);
965 NameBinding(Rc::new(RefCell::new(None)))
968 fn create_from_module(module: Rc<Module>) -> Self {
969 NameBinding(Rc::new(RefCell::new(Some(NsDef::create_from_module(module, None)))))
972 fn set(&self, ns_def: NsDef) {
973 *self.0.borrow_mut() = Some(ns_def);
976 fn set_modifiers(&self, modifiers: DefModifiers) {
977 if let Some(ref mut ns_def) = *self.0.borrow_mut() {
978 ns_def.modifiers = modifiers
982 fn borrow(&self) -> ::std::cell::Ref<Option<NsDef>> {
986 // Lifted versions of the NsDef methods and fields
987 fn def(&self) -> Option<Def> {
988 self.borrow().as_ref().and_then(NsDef::def)
990 fn module(&self) -> Option<Rc<Module>> {
991 self.borrow().as_ref().and_then(NsDef::module)
993 fn span(&self) -> Option<Span> {
994 self.borrow().as_ref().and_then(|def| def.span)
996 fn modifiers(&self) -> Option<DefModifiers> {
997 self.borrow().as_ref().and_then(|def| Some(def.modifiers))
1000 fn defined(&self) -> bool {
1001 self.borrow().is_some()
1004 fn defined_with(&self, modifiers: DefModifiers) -> bool {
1005 self.modifiers().map(|m| m.contains(modifiers)).unwrap_or(false)
1008 fn is_public(&self) -> bool {
1009 self.defined_with(DefModifiers::PUBLIC)
1012 fn def_and_lp(&self) -> (Def, LastPrivate) {
1013 let def = self.def().unwrap();
1014 (def, LastMod(if self.is_public() { AllPublic } else { DependsOn(def.def_id()) }))
1018 // Records the definitions (at most one for each namespace) that a name is
1020 #[derive(Clone,Debug)]
1021 pub struct NameBindings {
1022 type_ns: NameBinding, // < Meaning in type namespace.
1023 value_ns: NameBinding, // < Meaning in value namespace.
1026 impl ::std::ops::Index<Namespace> for NameBindings {
1027 type Output = NameBinding;
1028 fn index(&self, namespace: Namespace) -> &NameBinding {
1029 match namespace { TypeNS => &self.type_ns, ValueNS => &self.value_ns }
1034 fn new() -> NameBindings {
1036 type_ns: NameBinding::new(),
1037 value_ns: NameBinding::new(),
1041 fn create_from_module(module: Rc<Module>) -> NameBindings {
1043 type_ns: NameBinding::create_from_module(module),
1044 value_ns: NameBinding::new(),
1048 /// Creates a new module in this set of name bindings.
1049 fn define_module(&self, module: Rc<Module>, sp: Span) {
1050 self.type_ns.set(NsDef::create_from_module(module, Some(sp)));
1053 /// Records a type definition.
1054 fn define_type(&self, def: Def, sp: Span, modifiers: DefModifiers) {
1055 debug!("defining type for def {:?} with modifiers {:?}", def, modifiers);
1056 self.type_ns.set(NsDef::create_from_def(def, modifiers, Some(sp)));
1059 /// Records a value definition.
1060 fn define_value(&self, def: Def, sp: Span, modifiers: DefModifiers) {
1061 debug!("defining value for def {:?} with modifiers {:?}", def, modifiers);
1062 self.value_ns.set(NsDef::create_from_def(def, modifiers, Some(sp)));
1066 /// Interns the names of the primitive types.
1067 struct PrimitiveTypeTable {
1068 primitive_types: HashMap<Name, PrimTy>,
1071 impl PrimitiveTypeTable {
1072 fn new() -> PrimitiveTypeTable {
1073 let mut table = PrimitiveTypeTable { primitive_types: HashMap::new() };
1075 table.intern("bool", TyBool);
1076 table.intern("char", TyChar);
1077 table.intern("f32", TyFloat(TyF32));
1078 table.intern("f64", TyFloat(TyF64));
1079 table.intern("isize", TyInt(TyIs));
1080 table.intern("i8", TyInt(TyI8));
1081 table.intern("i16", TyInt(TyI16));
1082 table.intern("i32", TyInt(TyI32));
1083 table.intern("i64", TyInt(TyI64));
1084 table.intern("str", TyStr);
1085 table.intern("usize", TyUint(TyUs));
1086 table.intern("u8", TyUint(TyU8));
1087 table.intern("u16", TyUint(TyU16));
1088 table.intern("u32", TyUint(TyU32));
1089 table.intern("u64", TyUint(TyU64));
1094 fn intern(&mut self, string: &str, primitive_type: PrimTy) {
1095 self.primitive_types.insert(token::intern(string), primitive_type);
1099 /// The main resolver class.
1100 pub struct Resolver<'a, 'tcx: 'a> {
1101 session: &'a Session,
1103 ast_map: &'a hir_map::Map<'tcx>,
1105 graph_root: Rc<Module>,
1107 trait_item_map: FnvHashMap<(Name, DefId), DefId>,
1109 structs: FnvHashMap<DefId, Vec<Name>>,
1111 // The number of imports that are currently unresolved.
1112 unresolved_imports: usize,
1114 // The module that represents the current item scope.
1115 current_module: Rc<Module>,
1117 // The current set of local scopes, for values.
1118 // FIXME #4948: Reuse ribs to avoid allocation.
1119 value_ribs: Vec<Rib>,
1121 // The current set of local scopes, for types.
1122 type_ribs: Vec<Rib>,
1124 // The current set of local scopes, for labels.
1125 label_ribs: Vec<Rib>,
1127 // The trait that the current context can refer to.
1128 current_trait_ref: Option<(DefId, TraitRef)>,
1130 // The current self type if inside an impl (used for better errors).
1131 current_self_type: Option<Ty>,
1133 // The idents for the primitive types.
1134 primitive_type_table: PrimitiveTypeTable,
1136 def_map: RefCell<DefMap>,
1137 freevars: FreevarMap,
1138 freevars_seen: NodeMap<NodeMap<usize>>,
1139 export_map: ExportMap,
1140 trait_map: TraitMap,
1141 external_exports: ExternalExports,
1143 // Whether or not to print error messages. Can be set to true
1144 // when getting additional info for error message suggestions,
1145 // so as to avoid printing duplicate errors
1148 make_glob_map: bool,
1149 // Maps imports to the names of items actually imported (this actually maps
1150 // all imports, but only glob imports are actually interesting).
1153 used_imports: HashSet<(NodeId, Namespace)>,
1154 used_crates: HashSet<CrateNum>,
1156 // Callback function for intercepting walks
1157 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>,
1158 // The intention is that the callback modifies this flag.
1159 // Once set, the resolver falls out of the walk, preserving the ribs.
1163 #[derive(PartialEq)]
1164 enum FallbackChecks {
1166 OnlyTraitAndStatics,
1169 impl<'a, 'tcx> Resolver<'a, 'tcx> {
1170 fn new(session: &'a Session,
1171 ast_map: &'a hir_map::Map<'tcx>,
1172 make_glob_map: MakeGlobMap)
1173 -> Resolver<'a, 'tcx> {
1174 let root_def_id = ast_map.local_def_id(CRATE_NODE_ID);
1175 let graph_root = Module::new(NoParentLink, Some(DefMod(root_def_id)), false, true);
1182 // The outermost module has def ID 0; this is not reflected in the
1184 graph_root: graph_root.clone(),
1186 trait_item_map: FnvHashMap(),
1187 structs: FnvHashMap(),
1189 unresolved_imports: 0,
1191 current_module: graph_root,
1192 value_ribs: Vec::new(),
1193 type_ribs: Vec::new(),
1194 label_ribs: Vec::new(),
1196 current_trait_ref: None,
1197 current_self_type: None,
1199 primitive_type_table: PrimitiveTypeTable::new(),
1201 def_map: RefCell::new(NodeMap()),
1202 freevars: NodeMap(),
1203 freevars_seen: NodeMap(),
1204 export_map: NodeMap(),
1205 trait_map: NodeMap(),
1206 used_imports: HashSet::new(),
1207 used_crates: HashSet::new(),
1208 external_exports: DefIdSet(),
1211 make_glob_map: make_glob_map == MakeGlobMap::Yes,
1212 glob_map: HashMap::new(),
1220 fn record_import_use(&mut self, import_id: NodeId, name: Name) {
1221 if !self.make_glob_map {
1224 if self.glob_map.contains_key(&import_id) {
1225 self.glob_map.get_mut(&import_id).unwrap().insert(name);
1229 let mut new_set = HashSet::new();
1230 new_set.insert(name);
1231 self.glob_map.insert(import_id, new_set);
1234 fn get_trait_name(&self, did: DefId) -> Name {
1235 if let Some(node_id) = self.ast_map.as_local_node_id(did) {
1236 self.ast_map.expect_item(node_id).name
1238 csearch::get_trait_name(&self.session.cstore, did)
1242 /// Checks that the names of external crates don't collide with other
1243 /// external crates.
1244 fn check_for_conflicts_between_external_crates(&self,
1248 if module.external_module_children.borrow().contains_key(&name) {
1249 span_err!(self.session,
1252 "an external crate named `{}` has already been imported into this module",
1257 /// Checks that the names of items don't collide with external crates.
1258 fn check_for_conflicts_between_external_crates_and_items(&self,
1262 if module.external_module_children.borrow().contains_key(&name) {
1263 span_err!(self.session,
1266 "the name `{}` conflicts with an external crate that has been imported \
1272 /// Resolves the given module path from the given root `module_`.
1273 fn resolve_module_path_from_root(&mut self,
1274 module_: Rc<Module>,
1275 module_path: &[Name],
1278 name_search_type: NameSearchType,
1280 -> ResolveResult<(Rc<Module>, LastPrivate)> {
1281 fn search_parent_externals(needle: Name, module: &Rc<Module>) -> Option<Rc<Module>> {
1282 match module.external_module_children.borrow().get(&needle) {
1283 Some(_) => Some(module.clone()),
1284 None => match module.parent_link {
1285 ModuleParentLink(ref parent, _) => {
1286 search_parent_externals(needle, &parent.upgrade().unwrap())
1293 let mut search_module = module_;
1294 let mut index = index;
1295 let module_path_len = module_path.len();
1296 let mut closest_private = lp;
1298 // Resolve the module part of the path. This does not involve looking
1299 // upward though scope chains; we simply resolve names directly in
1300 // modules as we go.
1301 while index < module_path_len {
1302 let name = module_path[index];
1303 match self.resolve_name_in_module(search_module.clone(),
1309 let segment_name = name.as_str();
1310 let module_name = module_to_string(&*search_module);
1311 let mut span = span;
1312 let msg = if "???" == &module_name[..] {
1313 span.hi = span.lo + Pos::from_usize(segment_name.len());
1315 match search_parent_externals(name, &self.current_module) {
1317 let path_str = names_to_string(module_path);
1318 let target_mod_str = module_to_string(&*module);
1319 let current_mod_str = module_to_string(&*self.current_module);
1321 let prefix = if target_mod_str == current_mod_str {
1322 "self::".to_string()
1324 format!("{}::", target_mod_str)
1327 format!("Did you mean `{}{}`?", prefix, path_str)
1329 None => format!("Maybe a missing `extern crate {}`?", segment_name),
1332 format!("Could not find `{}` in `{}`", segment_name, module_name)
1335 return Failed(Some((span, msg)));
1337 Failed(err) => return Failed(err),
1339 debug!("(resolving module path for import) module resolution is \
1342 return Indeterminate;
1344 Success((target, used_proxy)) => {
1345 // Check to see whether there are type bindings, and, if
1346 // so, whether there is a module within.
1347 if let Some(module_def) = target.binding.module() {
1348 // track extern crates for unused_extern_crate lint
1349 if let Some(did) = module_def.def_id() {
1350 self.used_crates.insert(did.krate);
1353 search_module = module_def;
1355 // Keep track of the closest private module used
1356 // when resolving this import chain.
1357 if !used_proxy && !search_module.is_public {
1358 if let Some(did) = search_module.def_id() {
1359 closest_private = LastMod(DependsOn(did));
1363 let msg = format!("Not a module `{}`", name);
1364 return Failed(Some((span, msg)));
1372 return Success((search_module, closest_private));
1375 /// Attempts to resolve the module part of an import directive or path
1376 /// rooted at the given module.
1378 /// On success, returns the resolved module, and the closest *private*
1379 /// module found to the destination when resolving this path.
1380 fn resolve_module_path(&mut self,
1381 module_: Rc<Module>,
1382 module_path: &[Name],
1383 use_lexical_scope: UseLexicalScopeFlag,
1385 name_search_type: NameSearchType)
1386 -> ResolveResult<(Rc<Module>, LastPrivate)> {
1387 let module_path_len = module_path.len();
1388 assert!(module_path_len > 0);
1390 debug!("(resolving module path for import) processing `{}` rooted at `{}`",
1391 names_to_string(module_path),
1392 module_to_string(&*module_));
1394 // Resolve the module prefix, if any.
1395 let module_prefix_result = self.resolve_module_prefix(module_.clone(), module_path);
1400 match module_prefix_result {
1402 let mpath = names_to_string(module_path);
1403 let mpath = &mpath[..];
1404 match mpath.rfind(':') {
1406 let msg = format!("Could not find `{}` in `{}`",
1407 // idx +- 1 to account for the
1408 // colons on either side
1411 return Failed(Some((span, msg)));
1414 return Failed(None);
1418 Failed(err) => return Failed(err),
1420 debug!("(resolving module path for import) indeterminate; bailing");
1421 return Indeterminate;
1423 Success(NoPrefixFound) => {
1424 // There was no prefix, so we're considering the first element
1425 // of the path. How we handle this depends on whether we were
1426 // instructed to use lexical scope or not.
1427 match use_lexical_scope {
1428 DontUseLexicalScope => {
1429 // This is a crate-relative path. We will start the
1430 // resolution process at index zero.
1431 search_module = self.graph_root.clone();
1433 last_private = LastMod(AllPublic);
1435 UseLexicalScope => {
1436 // This is not a crate-relative path. We resolve the
1437 // first component of the path in the current lexical
1438 // scope and then proceed to resolve below that.
1439 match self.resolve_module_in_lexical_scope(module_, module_path[0]) {
1440 Failed(err) => return Failed(err),
1442 debug!("(resolving module path for import) indeterminate; bailing");
1443 return Indeterminate;
1445 Success(containing_module) => {
1446 search_module = containing_module;
1448 last_private = LastMod(AllPublic);
1454 Success(PrefixFound(ref containing_module, index)) => {
1455 search_module = containing_module.clone();
1456 start_index = index;
1457 last_private = LastMod(DependsOn(containing_module.def_id()
1462 self.resolve_module_path_from_root(search_module,
1470 /// Invariant: This must only be called during main resolution, not during
1471 /// import resolution.
1472 fn resolve_item_in_lexical_scope(&mut self,
1473 module_: Rc<Module>,
1475 namespace: Namespace)
1476 -> ResolveResult<(Target, bool)> {
1477 debug!("(resolving item in lexical scope) resolving `{}` in namespace {:?} in `{}`",
1480 module_to_string(&*module_));
1482 // The current module node is handled specially. First, check for
1483 // its immediate children.
1484 build_reduced_graph::populate_module_if_necessary(self, &module_);
1486 match module_.children.borrow().get(&name) {
1487 Some(name_bindings) if name_bindings[namespace].defined() => {
1488 debug!("top name bindings succeeded");
1489 return Success((Target::new(module_.clone(),
1490 name_bindings[namespace].clone(),
1495 // Not found; continue.
1499 // Now check for its import directives. We don't have to have resolved
1500 // all its imports in the usual way; this is because chains of
1501 // adjacent import statements are processed as though they mutated the
1503 if let Some(import_resolution) = module_.import_resolutions.borrow().get(&name) {
1504 match (*import_resolution).target_for_namespace(namespace) {
1506 // Not found; continue.
1507 debug!("(resolving item in lexical scope) found import resolution, but not \
1512 debug!("(resolving item in lexical scope) using import resolution");
1513 // track used imports and extern crates as well
1514 let id = import_resolution.id(namespace);
1515 self.used_imports.insert((id, namespace));
1516 self.record_import_use(id, name);
1517 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
1518 self.used_crates.insert(kid);
1520 return Success((target, false));
1525 // Search for external modules.
1526 if namespace == TypeNS {
1527 // FIXME (21114): In principle unclear `child` *has* to be lifted.
1528 let child = module_.external_module_children.borrow().get(&name).cloned();
1529 if let Some(module) = child {
1530 let name_binding = NameBinding::create_from_module(module);
1531 debug!("lower name bindings succeeded");
1532 return Success((Target::new(module_, name_binding, Shadowable::Never),
1537 // Finally, proceed up the scope chain looking for parent modules.
1538 let mut search_module = module_;
1540 // Go to the next parent.
1541 match search_module.parent_link.clone() {
1543 // No more parents. This module was unresolved.
1544 debug!("(resolving item in lexical scope) unresolved module");
1545 return Failed(None);
1547 ModuleParentLink(parent_module_node, _) => {
1548 if search_module.is_normal() {
1549 // We stop the search here.
1550 debug!("(resolving item in lexical scope) unresolved module: not \
1551 searching through module parents");
1552 return Failed(None);
1554 search_module = parent_module_node.upgrade().unwrap();
1557 BlockParentLink(ref parent_module_node, _) => {
1558 search_module = parent_module_node.upgrade().unwrap();
1562 // Resolve the name in the parent module.
1563 match self.resolve_name_in_module(search_module.clone(),
1568 Failed(Some((span, msg))) => {
1569 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
1571 Failed(None) => (), // Continue up the search chain.
1573 // We couldn't see through the higher scope because of an
1574 // unresolved import higher up. Bail.
1576 debug!("(resolving item in lexical scope) indeterminate higher scope; bailing");
1577 return Indeterminate;
1579 Success((target, used_reexport)) => {
1580 // We found the module.
1581 debug!("(resolving item in lexical scope) found name in module, done");
1582 return Success((target, used_reexport));
1588 /// Resolves a module name in the current lexical scope.
1589 fn resolve_module_in_lexical_scope(&mut self,
1590 module_: Rc<Module>,
1592 -> ResolveResult<Rc<Module>> {
1593 // If this module is an anonymous module, resolve the item in the
1594 // lexical scope. Otherwise, resolve the item from the crate root.
1595 let resolve_result = self.resolve_item_in_lexical_scope(module_, name, TypeNS);
1596 match resolve_result {
1597 Success((target, _)) => {
1598 if let Some(module_def) = target.binding.module() {
1599 return Success(module_def)
1601 debug!("!!! (resolving module in lexical scope) module \
1602 wasn't actually a module!");
1603 return Failed(None);
1607 debug!("(resolving module in lexical scope) indeterminate; bailing");
1608 return Indeterminate;
1611 debug!("(resolving module in lexical scope) failed to resolve");
1617 /// Returns the nearest normal module parent of the given module.
1618 fn get_nearest_normal_module_parent(&mut self, module_: Rc<Module>) -> Option<Rc<Module>> {
1619 let mut module_ = module_;
1621 match module_.parent_link.clone() {
1622 NoParentLink => return None,
1623 ModuleParentLink(new_module, _) |
1624 BlockParentLink(new_module, _) => {
1625 let new_module = new_module.upgrade().unwrap();
1626 if new_module.is_normal() {
1627 return Some(new_module);
1629 module_ = new_module;
1635 /// Returns the nearest normal module parent of the given module, or the
1636 /// module itself if it is a normal module.
1637 fn get_nearest_normal_module_parent_or_self(&mut self, module_: Rc<Module>) -> Rc<Module> {
1638 if module_.is_normal() {
1641 match self.get_nearest_normal_module_parent(module_.clone()) {
1643 Some(new_module) => new_module,
1647 /// Resolves a "module prefix". A module prefix is one or both of (a) `self::`;
1648 /// (b) some chain of `super::`.
1649 /// grammar: (SELF MOD_SEP ) ? (SUPER MOD_SEP) *
1650 fn resolve_module_prefix(&mut self,
1651 module_: Rc<Module>,
1652 module_path: &[Name])
1653 -> ResolveResult<ModulePrefixResult> {
1654 // Start at the current module if we see `self` or `super`, or at the
1655 // top of the crate otherwise.
1656 let mut i = match &*module_path[0].as_str() {
1659 _ => return Success(NoPrefixFound),
1661 let mut containing_module = self.get_nearest_normal_module_parent_or_self(module_);
1663 // Now loop through all the `super`s we find.
1664 while i < module_path.len() && "super" == module_path[i].as_str() {
1665 debug!("(resolving module prefix) resolving `super` at {}",
1666 module_to_string(&*containing_module));
1667 match self.get_nearest_normal_module_parent(containing_module) {
1668 None => return Failed(None),
1669 Some(new_module) => {
1670 containing_module = new_module;
1676 debug!("(resolving module prefix) finished resolving prefix at {}",
1677 module_to_string(&*containing_module));
1679 return Success(PrefixFound(containing_module, i));
1682 /// Attempts to resolve the supplied name in the given module for the
1683 /// given namespace. If successful, returns the target corresponding to
1686 /// The boolean returned on success is an indicator of whether this lookup
1687 /// passed through a public re-export proxy.
1688 fn resolve_name_in_module(&mut self,
1689 module_: Rc<Module>,
1691 namespace: Namespace,
1692 name_search_type: NameSearchType,
1693 allow_private_imports: bool)
1694 -> ResolveResult<(Target, bool)> {
1695 debug!("(resolving name in module) resolving `{}` in `{}`",
1697 module_to_string(&*module_));
1699 // First, check the direct children of the module.
1700 build_reduced_graph::populate_module_if_necessary(self, &module_);
1702 match module_.children.borrow().get(&name) {
1703 Some(name_bindings) if name_bindings[namespace].defined() => {
1704 debug!("(resolving name in module) found node as child");
1705 return Success((Target::new(module_.clone(),
1706 name_bindings[namespace].clone(),
1715 // Next, check the module's imports if necessary.
1717 // If this is a search of all imports, we should be done with glob
1718 // resolution at this point.
1719 if name_search_type == PathSearch {
1720 assert_eq!(module_.glob_count.get(), 0);
1723 // Check the list of resolved imports.
1724 match module_.import_resolutions.borrow().get(&name) {
1725 Some(import_resolution) if allow_private_imports || import_resolution.is_public => {
1727 if import_resolution.is_public && import_resolution.outstanding_references != 0 {
1728 debug!("(resolving name in module) import unresolved; bailing out");
1729 return Indeterminate;
1731 match import_resolution.target_for_namespace(namespace) {
1733 debug!("(resolving name in module) name found, but not in namespace {:?}",
1737 debug!("(resolving name in module) resolved to import");
1738 // track used imports and extern crates as well
1739 let id = import_resolution.id(namespace);
1740 self.used_imports.insert((id, namespace));
1741 self.record_import_use(id, name);
1742 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
1743 self.used_crates.insert(kid);
1745 return Success((target, true));
1749 Some(..) | None => {} // Continue.
1752 // Finally, search through external children.
1753 if namespace == TypeNS {
1754 // FIXME (21114): In principle unclear `child` *has* to be lifted.
1755 let child = module_.external_module_children.borrow().get(&name).cloned();
1756 if let Some(module) = child {
1757 let name_binding = NameBinding::create_from_module(module);
1758 return Success((Target::new(module_, name_binding, Shadowable::Never),
1763 // We're out of luck.
1764 debug!("(resolving name in module) failed to resolve `{}`", name);
1765 return Failed(None);
1768 fn report_unresolved_imports(&mut self, module_: Rc<Module>) {
1769 let index = module_.resolved_import_count.get();
1770 let imports = module_.imports.borrow();
1771 let import_count = imports.len();
1772 if index != import_count {
1774 (*imports)[index].span,
1775 ResolutionError::UnresolvedImport(None));
1778 // Descend into children and anonymous children.
1779 build_reduced_graph::populate_module_if_necessary(self, &module_);
1781 for (_, child_node) in module_.children.borrow().iter() {
1782 match child_node.type_ns.module() {
1786 Some(child_module) => {
1787 self.report_unresolved_imports(child_module);
1792 for (_, module_) in module_.anonymous_children.borrow().iter() {
1793 self.report_unresolved_imports(module_.clone());
1799 // We maintain a list of value ribs and type ribs.
1801 // Simultaneously, we keep track of the current position in the module
1802 // graph in the `current_module` pointer. When we go to resolve a name in
1803 // the value or type namespaces, we first look through all the ribs and
1804 // then query the module graph. When we resolve a name in the module
1805 // namespace, we can skip all the ribs (since nested modules are not
1806 // allowed within blocks in Rust) and jump straight to the current module
1809 // Named implementations are handled separately. When we find a method
1810 // call, we consult the module node to find all of the implementations in
1811 // scope. This information is lazily cached in the module node. We then
1812 // generate a fake "implementation scope" containing all the
1813 // implementations thus found, for compatibility with old resolve pass.
1815 fn with_scope<F>(&mut self, name: Option<Name>, f: F)
1816 where F: FnOnce(&mut Resolver)
1818 let orig_module = self.current_module.clone();
1820 // Move down in the graph.
1826 build_reduced_graph::populate_module_if_necessary(self, &orig_module);
1828 match orig_module.children.borrow().get(&name) {
1830 debug!("!!! (with scope) didn't find `{}` in `{}`",
1832 module_to_string(&*orig_module));
1834 Some(name_bindings) => {
1835 match name_bindings.type_ns.module() {
1837 debug!("!!! (with scope) didn't find module for `{}` in `{}`",
1839 module_to_string(&*orig_module));
1842 self.current_module = module_;
1852 self.current_module = orig_module;
1855 /// Searches the current set of local scopes for labels.
1856 /// Stops after meeting a closure.
1857 fn search_label(&self, name: Name) -> Option<DefLike> {
1858 for rib in self.label_ribs.iter().rev() {
1864 // Do not resolve labels across function boundary
1868 let result = rib.bindings.get(&name).cloned();
1869 if result.is_some() {
1876 fn resolve_crate(&mut self, krate: &hir::Crate) {
1877 debug!("(resolving crate) starting");
1879 intravisit::walk_crate(self, krate);
1882 fn check_if_primitive_type_name(&self, name: Name, span: Span) {
1883 if let Some(_) = self.primitive_type_table.primitive_types.get(&name) {
1884 span_err!(self.session,
1887 "user-defined types or type parameters cannot shadow the primitive types");
1891 fn resolve_item(&mut self, item: &Item) {
1892 let name = item.name;
1894 debug!("(resolving item) resolving {}", name);
1897 ItemEnum(_, ref generics) |
1898 ItemTy(_, ref generics) |
1899 ItemStruct(_, ref generics) => {
1900 self.check_if_primitive_type_name(name, item.span);
1902 self.with_type_parameter_rib(HasTypeParameters(generics, TypeSpace, ItemRibKind),
1903 |this| intravisit::walk_item(this, item));
1905 ItemFn(_, _, _, _, ref generics, _) => {
1906 self.with_type_parameter_rib(HasTypeParameters(generics, FnSpace, ItemRibKind),
1907 |this| intravisit::walk_item(this, item));
1910 ItemDefaultImpl(_, ref trait_ref) => {
1911 self.with_optional_trait_ref(Some(trait_ref), |_, _| {});
1913 ItemImpl(_, _, ref generics, ref opt_trait_ref, ref self_type, ref impl_items) => {
1914 self.resolve_implementation(generics,
1921 ItemTrait(_, ref generics, ref bounds, ref trait_items) => {
1922 self.check_if_primitive_type_name(name, item.span);
1924 // Create a new rib for the trait-wide type parameters.
1925 self.with_type_parameter_rib(HasTypeParameters(generics,
1929 let local_def_id = this.ast_map.local_def_id(item.id);
1930 this.with_self_rib(DefSelfTy(Some(local_def_id), None), |this| {
1931 this.visit_generics(generics);
1932 walk_list!(this, visit_ty_param_bound, bounds);
1934 for trait_item in trait_items {
1935 match trait_item.node {
1936 hir::ConstTraitItem(_, ref default) => {
1937 // Only impose the restrictions of
1938 // ConstRibKind if there's an actual constant
1939 // expression in a provided default.
1940 if default.is_some() {
1941 this.with_constant_rib(|this| {
1942 intravisit::walk_trait_item(this, trait_item)
1945 intravisit::walk_trait_item(this, trait_item)
1948 hir::MethodTraitItem(ref sig, _) => {
1949 let type_parameters =
1950 HasTypeParameters(&sig.generics,
1953 this.with_type_parameter_rib(type_parameters, |this| {
1954 intravisit::walk_trait_item(this, trait_item)
1957 hir::TypeTraitItem(..) => {
1958 this.check_if_primitive_type_name(trait_item.name,
1960 this.with_type_parameter_rib(NoTypeParameters, |this| {
1961 intravisit::walk_trait_item(this, trait_item)
1970 ItemMod(_) | ItemForeignMod(_) => {
1971 self.with_scope(Some(name), |this| {
1972 intravisit::walk_item(this, item);
1976 ItemConst(..) | ItemStatic(..) => {
1977 self.with_constant_rib(|this| {
1978 intravisit::walk_item(this, item);
1982 ItemUse(ref view_path) => {
1983 // check for imports shadowing primitive types
1984 let check_rename = |this: &Self, id, name| {
1985 match this.def_map.borrow().get(&id).map(|d| d.full_def()) {
1986 Some(DefTy(..)) | Some(DefStruct(..)) | Some(DefTrait(..)) | None => {
1987 this.check_if_primitive_type_name(name, item.span);
1993 match view_path.node {
1994 hir::ViewPathSimple(name, _) => {
1995 check_rename(self, item.id, name);
1997 hir::ViewPathList(ref prefix, ref items) => {
1999 if let Some(name) = item.node.rename() {
2000 check_rename(self, item.node.id(), name);
2004 // Resolve prefix of an import with empty braces (issue #28388)
2005 if items.is_empty() && !prefix.segments.is_empty() {
2006 match self.resolve_crate_relative_path(prefix.span,
2010 self.record_def(item.id, PathResolution::new(def, lp, 0)),
2014 ResolutionError::FailedToResolve(
2015 &path_names_to_string(prefix, 0)));
2024 ItemExternCrate(_) => {
2025 // do nothing, these are just around to be encoded
2030 fn with_type_parameter_rib<F>(&mut self, type_parameters: TypeParameters, f: F)
2031 where F: FnOnce(&mut Resolver)
2033 match type_parameters {
2034 HasTypeParameters(generics, space, rib_kind) => {
2035 let mut function_type_rib = Rib::new(rib_kind);
2036 let mut seen_bindings = HashSet::new();
2037 for (index, type_parameter) in generics.ty_params.iter().enumerate() {
2038 let name = type_parameter.name;
2039 debug!("with_type_parameter_rib: {}", type_parameter.id);
2041 if seen_bindings.contains(&name) {
2043 type_parameter.span,
2044 ResolutionError::NameAlreadyUsedInTypeParameterList(name));
2046 seen_bindings.insert(name);
2048 // plain insert (no renaming)
2049 function_type_rib.bindings
2051 DlDef(DefTyParam(space,
2054 .local_def_id(type_parameter.id),
2057 self.type_ribs.push(function_type_rib);
2060 NoTypeParameters => {
2067 match type_parameters {
2068 HasTypeParameters(..) => {
2070 self.type_ribs.pop();
2073 NoTypeParameters => {}
2077 fn with_label_rib<F>(&mut self, f: F)
2078 where F: FnOnce(&mut Resolver)
2080 self.label_ribs.push(Rib::new(NormalRibKind));
2083 self.label_ribs.pop();
2087 fn with_constant_rib<F>(&mut self, f: F)
2088 where F: FnOnce(&mut Resolver)
2090 self.value_ribs.push(Rib::new(ConstantItemRibKind));
2091 self.type_ribs.push(Rib::new(ConstantItemRibKind));
2094 self.type_ribs.pop();
2095 self.value_ribs.pop();
2099 fn resolve_function(&mut self, rib_kind: RibKind, declaration: &FnDecl, block: &Block) {
2100 // Create a value rib for the function.
2101 self.value_ribs.push(Rib::new(rib_kind));
2103 // Create a label rib for the function.
2104 self.label_ribs.push(Rib::new(rib_kind));
2106 // Add each argument to the rib.
2107 let mut bindings_list = HashMap::new();
2108 for argument in &declaration.inputs {
2109 self.resolve_pattern(&*argument.pat, ArgumentIrrefutableMode, &mut bindings_list);
2111 self.visit_ty(&*argument.ty);
2113 debug!("(resolving function) recorded argument");
2115 intravisit::walk_fn_ret_ty(self, &declaration.output);
2117 // Resolve the function body.
2118 self.visit_block(block);
2120 debug!("(resolving function) leaving function");
2123 self.label_ribs.pop();
2124 self.value_ribs.pop();
2128 fn resolve_trait_reference(&mut self,
2132 -> Result<PathResolution, ()> {
2133 if let Some(path_res) = self.resolve_path(id, trait_path, path_depth, TypeNS, true) {
2134 if let DefTrait(_) = path_res.base_def {
2135 debug!("(resolving trait) found trait def: {:?}", path_res);
2140 ResolutionError::IsNotATrait(&*path_names_to_string(trait_path,
2143 // If it's a typedef, give a note
2144 if let DefTy(..) = path_res.base_def {
2146 .span_note(trait_path.span, "`type` aliases cannot be used for traits");
2153 ResolutionError::UndeclaredTraitName(&*path_names_to_string(trait_path,
2159 fn resolve_generics(&mut self, generics: &Generics) {
2160 for type_parameter in generics.ty_params.iter() {
2161 self.check_if_primitive_type_name(type_parameter.name, type_parameter.span);
2163 for predicate in &generics.where_clause.predicates {
2165 &hir::WherePredicate::BoundPredicate(_) |
2166 &hir::WherePredicate::RegionPredicate(_) => {}
2167 &hir::WherePredicate::EqPredicate(ref eq_pred) => {
2168 let path_res = self.resolve_path(eq_pred.id, &eq_pred.path, 0, TypeNS, true);
2169 if let Some(PathResolution { base_def: DefTyParam(..), .. }) = path_res {
2170 self.record_def(eq_pred.id, path_res.unwrap());
2174 ResolutionError::UndeclaredAssociatedType);
2179 intravisit::walk_generics(self, generics);
2182 fn with_current_self_type<T, F>(&mut self, self_type: &Ty, f: F) -> T
2183 where F: FnOnce(&mut Resolver) -> T
2185 // Handle nested impls (inside fn bodies)
2186 let previous_value = replace(&mut self.current_self_type, Some(self_type.clone()));
2187 let result = f(self);
2188 self.current_self_type = previous_value;
2192 fn with_optional_trait_ref<T, F>(&mut self, opt_trait_ref: Option<&TraitRef>, f: F) -> T
2193 where F: FnOnce(&mut Resolver, Option<DefId>) -> T
2195 let mut new_val = None;
2196 let mut new_id = None;
2197 if let Some(trait_ref) = opt_trait_ref {
2198 if let Ok(path_res) = self.resolve_trait_reference(trait_ref.ref_id,
2201 assert!(path_res.depth == 0);
2202 self.record_def(trait_ref.ref_id, path_res);
2203 new_val = Some((path_res.base_def.def_id(), trait_ref.clone()));
2204 new_id = Some(path_res.base_def.def_id());
2206 intravisit::walk_trait_ref(self, trait_ref);
2208 let original_trait_ref = replace(&mut self.current_trait_ref, new_val);
2209 let result = f(self, new_id);
2210 self.current_trait_ref = original_trait_ref;
2214 fn with_self_rib<F>(&mut self, self_def: Def, f: F)
2215 where F: FnOnce(&mut Resolver)
2217 let mut self_type_rib = Rib::new(NormalRibKind);
2219 // plain insert (no renaming, types are not currently hygienic....)
2220 let name = special_names::type_self;
2221 self_type_rib.bindings.insert(name, DlDef(self_def));
2222 self.type_ribs.push(self_type_rib);
2225 self.type_ribs.pop();
2229 fn resolve_implementation(&mut self,
2230 generics: &Generics,
2231 opt_trait_reference: &Option<TraitRef>,
2234 impl_items: &[P<ImplItem>]) {
2235 // If applicable, create a rib for the type parameters.
2236 self.with_type_parameter_rib(HasTypeParameters(generics,
2240 // Resolve the type parameters.
2241 this.visit_generics(generics);
2243 // Resolve the trait reference, if necessary.
2244 this.with_optional_trait_ref(opt_trait_reference.as_ref(), |this, trait_id| {
2245 // Resolve the self type.
2246 this.visit_ty(self_type);
2248 this.with_self_rib(DefSelfTy(trait_id, Some((item_id, self_type.id))), |this| {
2249 this.with_current_self_type(self_type, |this| {
2250 for impl_item in impl_items {
2251 match impl_item.node {
2252 hir::ImplItemKind::Const(..) => {
2253 // If this is a trait impl, ensure the const
2255 this.check_trait_item(impl_item.name,
2257 |n, s| ResolutionError::ConstNotMemberOfTrait(n, s));
2258 this.with_constant_rib(|this| {
2259 intravisit::walk_impl_item(this, impl_item);
2262 hir::ImplItemKind::Method(ref sig, _) => {
2263 // If this is a trait impl, ensure the method
2265 this.check_trait_item(impl_item.name,
2267 |n, s| ResolutionError::MethodNotMemberOfTrait(n, s));
2269 // We also need a new scope for the method-
2270 // specific type parameters.
2271 let type_parameters =
2272 HasTypeParameters(&sig.generics,
2275 this.with_type_parameter_rib(type_parameters, |this| {
2276 intravisit::walk_impl_item(this, impl_item);
2279 hir::ImplItemKind::Type(ref ty) => {
2280 // If this is a trait impl, ensure the type
2282 this.check_trait_item(impl_item.name,
2284 |n, s| ResolutionError::TypeNotMemberOfTrait(n, s));
2296 fn check_trait_item<F>(&self, name: Name, span: Span, err: F)
2297 where F: FnOnce(Name, &str) -> ResolutionError
2299 // If there is a TraitRef in scope for an impl, then the method must be in the
2301 if let Some((did, ref trait_ref)) = self.current_trait_ref {
2302 if !self.trait_item_map.contains_key(&(name, did)) {
2303 let path_str = path_names_to_string(&trait_ref.path, 0);
2304 resolve_error(self, span, err(name, &*path_str));
2309 fn resolve_local(&mut self, local: &Local) {
2310 // Resolve the type.
2311 walk_list!(self, visit_ty, &local.ty);
2313 // Resolve the initializer.
2314 walk_list!(self, visit_expr, &local.init);
2316 // Resolve the pattern.
2317 self.resolve_pattern(&*local.pat, LocalIrrefutableMode, &mut HashMap::new());
2320 // build a map from pattern identifiers to binding-info's.
2321 // this is done hygienically. This could arise for a macro
2322 // that expands into an or-pattern where one 'x' was from the
2323 // user and one 'x' came from the macro.
2324 fn binding_mode_map(&mut self, pat: &Pat) -> BindingMap {
2325 let mut result = HashMap::new();
2326 pat_bindings_hygienic(&self.def_map, pat, |binding_mode, _id, sp, path1| {
2327 let name = mtwt::resolve(path1.node);
2331 binding_mode: binding_mode,
2337 // check that all of the arms in an or-pattern have exactly the
2338 // same set of bindings, with the same binding modes for each.
2339 fn check_consistent_bindings(&mut self, arm: &Arm) {
2340 if arm.pats.is_empty() {
2343 let map_0 = self.binding_mode_map(&*arm.pats[0]);
2344 for (i, p) in arm.pats.iter().enumerate() {
2345 let map_i = self.binding_mode_map(&**p);
2347 for (&key, &binding_0) in &map_0 {
2348 match map_i.get(&key) {
2352 ResolutionError::VariableNotBoundInPattern(key, i + 1));
2354 Some(binding_i) => {
2355 if binding_0.binding_mode != binding_i.binding_mode {
2358 ResolutionError::VariableBoundWithDifferentMode(key,
2365 for (&key, &binding) in &map_i {
2366 if !map_0.contains_key(&key) {
2369 ResolutionError::VariableNotBoundInParentPattern(key, i + 1));
2375 fn resolve_arm(&mut self, arm: &Arm) {
2376 self.value_ribs.push(Rib::new(NormalRibKind));
2378 let mut bindings_list = HashMap::new();
2379 for pattern in &arm.pats {
2380 self.resolve_pattern(&**pattern, RefutableMode, &mut bindings_list);
2383 // This has to happen *after* we determine which
2384 // pat_idents are variants
2385 self.check_consistent_bindings(arm);
2387 walk_list!(self, visit_expr, &arm.guard);
2388 self.visit_expr(&*arm.body);
2391 self.value_ribs.pop();
2395 fn resolve_block(&mut self, block: &Block) {
2396 debug!("(resolving block) entering block");
2397 self.value_ribs.push(Rib::new(NormalRibKind));
2399 // Move down in the graph, if there's an anonymous module rooted here.
2400 let orig_module = self.current_module.clone();
2401 match orig_module.anonymous_children.borrow().get(&block.id) {
2405 Some(anonymous_module) => {
2406 debug!("(resolving block) found anonymous module, moving down");
2407 self.current_module = anonymous_module.clone();
2411 // Check for imports appearing after non-item statements.
2412 let mut found_non_item = false;
2413 for statement in &block.stmts {
2414 if let hir::StmtDecl(ref declaration, _) = statement.node {
2415 if let hir::DeclItem(i) = declaration.node {
2416 let i = self.ast_map.expect_item(i.id);
2418 ItemExternCrate(_) | ItemUse(_) if found_non_item => {
2419 span_err!(self.session,
2422 "imports are not allowed after non-item statements");
2427 found_non_item = true
2430 found_non_item = true;
2434 // Descend into the block.
2435 intravisit::walk_block(self, block);
2439 self.current_module = orig_module;
2440 self.value_ribs.pop();
2442 debug!("(resolving block) leaving block");
2445 fn resolve_type(&mut self, ty: &Ty) {
2447 TyPath(ref maybe_qself, ref path) => {
2448 let resolution = match self.resolve_possibly_assoc_item(ty.id,
2449 maybe_qself.as_ref(),
2453 // `<T>::a::b::c` is resolved by typeck alone.
2454 TypecheckRequired => {
2455 // Resolve embedded types.
2456 intravisit::walk_ty(self, ty);
2459 ResolveAttempt(resolution) => resolution,
2462 // This is a path in the type namespace. Walk through scopes
2466 // Write the result into the def map.
2467 debug!("(resolving type) writing resolution for `{}` (id {}) = {:?}",
2468 path_names_to_string(path, 0),
2471 self.record_def(ty.id, def);
2474 // Keep reporting some errors even if they're ignored above.
2475 self.resolve_path(ty.id, path, 0, TypeNS, true);
2477 let kind = if maybe_qself.is_some() {
2483 let self_type_name = special_idents::type_self.name;
2484 let is_invalid_self_type_name = path.segments.len() > 0 &&
2485 maybe_qself.is_none() &&
2486 path.segments[0].identifier.name ==
2488 if is_invalid_self_type_name {
2491 ResolutionError::SelfUsedOutsideImplOrTrait);
2495 ResolutionError::UseOfUndeclared(
2497 &*path_names_to_string(path,
2506 // Resolve embedded types.
2507 intravisit::walk_ty(self, ty);
2510 fn resolve_pattern(&mut self,
2512 mode: PatternBindingMode,
2513 // Maps idents to the node ID for the (outermost)
2514 // pattern that binds them
2515 bindings_list: &mut HashMap<Name, NodeId>) {
2516 let pat_id = pattern.id;
2517 walk_pat(pattern, |pattern| {
2518 match pattern.node {
2519 PatIdent(binding_mode, ref path1, ref at_rhs) => {
2520 // The meaning of PatIdent with no type parameters
2521 // depends on whether an enum variant or unit-like struct
2522 // with that name is in scope. The probing lookup has to
2523 // be careful not to emit spurious errors. Only matching
2524 // patterns (match) can match nullary variants or
2525 // unit-like structs. For binding patterns (let
2526 // and the LHS of @-patterns), matching such a value is
2527 // simply disallowed (since it's rarely what you want).
2528 let const_ok = mode == RefutableMode && at_rhs.is_none();
2530 let ident = path1.node;
2531 let renamed = mtwt::resolve(ident);
2533 match self.resolve_bare_identifier_pattern(ident.name, pattern.span) {
2534 FoundStructOrEnumVariant(def, lp) if const_ok => {
2535 debug!("(resolving pattern) resolving `{}` to struct or enum variant",
2538 self.enforce_default_binding_mode(pattern,
2541 self.record_def(pattern.id,
2548 FoundStructOrEnumVariant(..) => {
2552 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(
2556 FoundConst(def, lp, _) if const_ok => {
2557 debug!("(resolving pattern) resolving `{}` to constant", renamed);
2559 self.enforce_default_binding_mode(pattern, binding_mode, "a constant");
2560 self.record_def(pattern.id,
2567 FoundConst(def, _, name) => {
2571 ResolutionError::OnlyIrrefutablePatternsAllowedHere(def.def_id(),
2575 BareIdentifierPatternUnresolved => {
2576 debug!("(resolving pattern) binding `{}`", renamed);
2578 let def_id = self.ast_map.local_def_id(pattern.id);
2579 let def = DefLocal(def_id, pattern.id);
2581 // Record the definition so that later passes
2582 // will be able to distinguish variants from
2583 // locals in patterns.
2585 self.record_def(pattern.id,
2588 last_private: LastMod(AllPublic),
2592 // Add the binding to the local ribs, if it
2593 // doesn't already exist in the bindings list. (We
2594 // must not add it if it's in the bindings list
2595 // because that breaks the assumptions later
2596 // passes make about or-patterns.)
2597 if !bindings_list.contains_key(&renamed) {
2598 let this = &mut *self;
2599 let last_rib = this.value_ribs.last_mut().unwrap();
2600 last_rib.bindings.insert(renamed, DlDef(def));
2601 bindings_list.insert(renamed, pat_id);
2602 } else if mode == ArgumentIrrefutableMode &&
2603 bindings_list.contains_key(&renamed) {
2604 // Forbid duplicate bindings in the same
2609 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(
2610 &ident.name.as_str())
2612 } else if bindings_list.get(&renamed) == Some(&pat_id) {
2613 // Then this is a duplicate variable in the
2614 // same disjunction, which is an error.
2618 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(
2619 &ident.name.as_str())
2622 // Else, not bound in the same pattern: do
2628 PatEnum(ref path, _) => {
2629 // This must be an enum variant, struct or const.
2630 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2635 // The below shouldn't happen because all
2636 // qualified paths should be in PatQPath.
2637 TypecheckRequired =>
2638 self.session.span_bug(path.span,
2639 "resolve_possibly_assoc_item claimed
2641 that a path in PatEnum requires typecheck
2643 to resolve, but qualified paths should be
2646 ResolveAttempt(resolution) => resolution,
2648 if let Some(path_res) = resolution {
2649 match path_res.base_def {
2650 DefVariant(..) | DefStruct(..) | DefConst(..) => {
2651 self.record_def(pattern.id, path_res);
2654 resolve_error(&self,
2656 ResolutionError::StaticVariableReference);
2659 // If anything ends up here entirely resolved,
2660 // it's an error. If anything ends up here
2661 // partially resolved, that's OK, because it may
2662 // be a `T::CONST` that typeck will resolve.
2663 if path_res.depth == 0 {
2667 ResolutionError::NotAnEnumVariantStructOrConst(
2676 let const_name = path.segments
2681 let traits = self.get_traits_containing_item(const_name);
2682 self.trait_map.insert(pattern.id, traits);
2683 self.record_def(pattern.id, path_res);
2691 ResolutionError::UnresolvedEnumVariantStructOrConst(
2692 &path.segments.last().unwrap().identifier.name.as_str())
2695 intravisit::walk_path(self, path);
2698 PatQPath(ref qself, ref path) => {
2699 // Associated constants only.
2700 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2705 TypecheckRequired => {
2706 // All `<T>::CONST` should end up here, and will
2707 // require use of the trait map to resolve
2708 // during typechecking.
2709 let const_name = path.segments
2714 let traits = self.get_traits_containing_item(const_name);
2715 self.trait_map.insert(pattern.id, traits);
2716 intravisit::walk_pat(self, pattern);
2719 ResolveAttempt(resolution) => resolution,
2721 if let Some(path_res) = resolution {
2722 match path_res.base_def {
2723 // All `<T as Trait>::CONST` should end up here, and
2724 // have the trait already selected.
2725 DefAssociatedConst(..) => {
2726 self.record_def(pattern.id, path_res);
2732 ResolutionError::NotAnAssociatedConst(
2733 &path.segments.last().unwrap().identifier.name.as_str()
2741 ResolutionError::UnresolvedAssociatedConst(&path.segments
2748 intravisit::walk_pat(self, pattern);
2751 PatStruct(ref path, _, _) => {
2752 match self.resolve_path(pat_id, path, 0, TypeNS, false) {
2753 Some(definition) => {
2754 self.record_def(pattern.id, definition);
2757 debug!("(resolving pattern) didn't find struct def: {:?}", result);
2761 ResolutionError::DoesNotNameAStruct(
2762 &*path_names_to_string(path, 0))
2766 intravisit::walk_path(self, path);
2769 PatLit(_) | PatRange(..) => {
2770 intravisit::walk_pat(self, pattern);
2781 fn resolve_bare_identifier_pattern(&mut self,
2784 -> BareIdentifierPatternResolution {
2785 let module = self.current_module.clone();
2786 match self.resolve_item_in_lexical_scope(module, name, ValueNS) {
2787 Success((target, _)) => {
2788 debug!("(resolve bare identifier pattern) succeeded in finding {} at {:?}",
2790 target.binding.borrow());
2791 match target.binding.def() {
2793 panic!("resolved name in the value namespace to a set of name bindings \
2796 // For the two success cases, this lookup can be
2797 // considered as not having a private component because
2798 // the lookup happened only within the current module.
2799 Some(def @ DefVariant(..)) | Some(def @ DefStruct(..)) => {
2800 return FoundStructOrEnumVariant(def, LastMod(AllPublic));
2802 Some(def @ DefConst(..)) | Some(def @ DefAssociatedConst(..)) => {
2803 return FoundConst(def, LastMod(AllPublic), name);
2805 Some(DefStatic(..)) => {
2806 resolve_error(self, span, ResolutionError::StaticVariableReference);
2807 return BareIdentifierPatternUnresolved;
2809 _ => return BareIdentifierPatternUnresolved
2814 panic!("unexpected indeterminate result");
2818 Some((span, msg)) => {
2819 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
2824 debug!("(resolve bare identifier pattern) failed to find {}", name);
2825 return BareIdentifierPatternUnresolved;
2830 /// Handles paths that may refer to associated items
2831 fn resolve_possibly_assoc_item(&mut self,
2833 maybe_qself: Option<&hir::QSelf>,
2835 namespace: Namespace,
2837 -> AssocItemResolveResult {
2838 let max_assoc_types;
2842 if qself.position == 0 {
2843 return TypecheckRequired;
2845 max_assoc_types = path.segments.len() - qself.position;
2846 // Make sure the trait is valid.
2847 let _ = self.resolve_trait_reference(id, path, max_assoc_types);
2850 max_assoc_types = path.segments.len();
2854 let mut resolution = self.with_no_errors(|this| {
2855 this.resolve_path(id, path, 0, namespace, check_ribs)
2857 for depth in 1..max_assoc_types {
2858 if resolution.is_some() {
2861 self.with_no_errors(|this| {
2862 resolution = this.resolve_path(id, path, depth, TypeNS, true);
2865 if let Some(DefMod(_)) = resolution.map(|r| r.base_def) {
2866 // A module is not a valid type or value.
2869 ResolveAttempt(resolution)
2872 /// If `check_ribs` is true, checks the local definitions first; i.e.
2873 /// doesn't skip straight to the containing module.
2874 /// Skips `path_depth` trailing segments, which is also reflected in the
2875 /// returned value. See `middle::def::PathResolution` for more info.
2876 pub fn resolve_path(&mut self,
2880 namespace: Namespace,
2882 -> Option<PathResolution> {
2883 let span = path.span;
2884 let segments = &path.segments[..path.segments.len() - path_depth];
2886 let mk_res = |(def, lp)| PathResolution::new(def, lp, path_depth);
2889 let def = self.resolve_crate_relative_path(span, segments, namespace);
2890 return def.map(mk_res);
2893 // Try to find a path to an item in a module.
2894 let unqualified_def = self.resolve_identifier(segments.last().unwrap().identifier,
2898 if segments.len() <= 1 {
2899 return unqualified_def.and_then(|def| self.adjust_local_def(def, span))
2901 PathResolution::new(def, LastMod(AllPublic), path_depth)
2905 let def = self.resolve_module_relative_path(span, segments, namespace);
2906 match (def, unqualified_def) {
2907 (Some((ref d, _)), Some(ref ud)) if *d == ud.def => {
2909 .add_lint(lint::builtin::UNUSED_QUALIFICATIONS,
2912 "unnecessary qualification".to_string());
2920 // Resolve a single identifier
2921 fn resolve_identifier(&mut self,
2923 namespace: Namespace,
2925 -> Option<LocalDef> {
2926 // First, check to see whether the name is a primitive type.
2927 if namespace == TypeNS {
2928 if let Some(&prim_ty) = self.primitive_type_table
2930 .get(&identifier.name) {
2931 return Some(LocalDef::from_def(DefPrimTy(prim_ty)));
2936 if let Some(def) = self.resolve_identifier_in_local_ribs(identifier, namespace) {
2941 self.resolve_item_by_name_in_lexical_scope(identifier.name, namespace)
2942 .map(LocalDef::from_def)
2945 // Resolve a local definition, potentially adjusting for closures.
2946 fn adjust_local_def(&mut self, local_def: LocalDef, span: Span) -> Option<Def> {
2947 let ribs = match local_def.ribs {
2948 Some((TypeNS, i)) => &self.type_ribs[i + 1..],
2949 Some((ValueNS, i)) => &self.value_ribs[i + 1..],
2952 let mut def = local_def.def;
2955 self.session.span_bug(span, &format!("unexpected {:?} in bindings", def))
2957 DefLocal(_, node_id) => {
2961 // Nothing to do. Continue.
2963 ClosureRibKind(function_id) => {
2965 let node_def_id = self.ast_map.local_def_id(node_id);
2967 let seen = self.freevars_seen
2969 .or_insert_with(|| NodeMap());
2970 if let Some(&index) = seen.get(&node_id) {
2971 def = DefUpvar(node_def_id, node_id, index, function_id);
2974 let vec = self.freevars
2976 .or_insert_with(|| vec![]);
2977 let depth = vec.len();
2983 def = DefUpvar(node_def_id, node_id, depth, function_id);
2984 seen.insert(node_id, depth);
2986 ItemRibKind | MethodRibKind => {
2987 // This was an attempt to access an upvar inside a
2988 // named function item. This is not allowed, so we
2992 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem);
2995 ConstantItemRibKind => {
2996 // Still doesn't deal with upvars
2999 ResolutionError::AttemptToUseNonConstantValueInConstant);
3005 DefTyParam(..) | DefSelfTy(..) => {
3008 NormalRibKind | MethodRibKind | ClosureRibKind(..) => {
3009 // Nothing to do. Continue.
3012 // This was an attempt to use a type parameter outside
3017 ResolutionError::TypeParametersFromOuterFunction);
3020 ConstantItemRibKind => {
3022 resolve_error(self, span, ResolutionError::OuterTypeParameterContext);
3033 // resolve a "module-relative" path, e.g. a::b::c
3034 fn resolve_module_relative_path(&mut self,
3036 segments: &[hir::PathSegment],
3037 namespace: Namespace)
3038 -> Option<(Def, LastPrivate)> {
3039 let module_path = segments.split_last()
3043 .map(|ps| ps.identifier.name)
3044 .collect::<Vec<_>>();
3046 let containing_module;
3048 let current_module = self.current_module.clone();
3049 match self.resolve_module_path(current_module,
3055 let (span, msg) = match err {
3056 Some((span, msg)) => (span, msg),
3058 let msg = format!("Use of undeclared type or module `{}`",
3059 names_to_string(&module_path));
3064 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
3067 Indeterminate => panic!("indeterminate unexpected"),
3068 Success((resulting_module, resulting_last_private)) => {
3069 containing_module = resulting_module;
3070 last_private = resulting_last_private;
3074 let name = segments.last().unwrap().identifier.name;
3075 let def = match self.resolve_name_in_module(containing_module.clone(),
3078 NameSearchType::PathSearch,
3080 Success((Target { binding, .. }, _)) => {
3081 let (def, lp) = binding.def_and_lp();
3082 (def, last_private.or(lp))
3086 if let Some(DefId{krate: kid, ..}) = containing_module.def_id() {
3087 self.used_crates.insert(kid);
3092 /// Invariant: This must be called only during main resolution, not during
3093 /// import resolution.
3094 fn resolve_crate_relative_path(&mut self,
3096 segments: &[hir::PathSegment],
3097 namespace: Namespace)
3098 -> Option<(Def, LastPrivate)> {
3099 let module_path = segments.split_last()
3103 .map(|ps| ps.identifier.name)
3104 .collect::<Vec<_>>();
3106 let root_module = self.graph_root.clone();
3108 let containing_module;
3110 match self.resolve_module_path_from_root(root_module,
3115 LastMod(AllPublic)) {
3117 let (span, msg) = match err {
3118 Some((span, msg)) => (span, msg),
3120 let msg = format!("Use of undeclared module `::{}`",
3121 names_to_string(&module_path[..]));
3126 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
3131 panic!("indeterminate unexpected");
3134 Success((resulting_module, resulting_last_private)) => {
3135 containing_module = resulting_module;
3136 last_private = resulting_last_private;
3140 let name = segments.last().unwrap().identifier.name;
3141 match self.resolve_name_in_module(containing_module,
3144 NameSearchType::PathSearch,
3146 Success((Target { binding, .. }, _)) => {
3147 let (def, lp) = binding.def_and_lp();
3148 Some((def, last_private.or(lp)))
3154 fn resolve_identifier_in_local_ribs(&mut self,
3156 namespace: Namespace)
3157 -> Option<LocalDef> {
3158 // Check the local set of ribs.
3159 let (name, ribs) = match namespace {
3160 ValueNS => (mtwt::resolve(ident), &self.value_ribs),
3161 TypeNS => (ident.name, &self.type_ribs),
3164 for (i, rib) in ribs.iter().enumerate().rev() {
3165 if let Some(def_like) = rib.bindings.get(&name).cloned() {
3168 debug!("(resolving path in local ribs) resolved `{}` to {:?} at {}",
3172 return Some(LocalDef {
3173 ribs: Some((namespace, i)),
3178 debug!("(resolving path in local ribs) resolved `{}` to pseudo-def {:?}",
3190 fn resolve_item_by_name_in_lexical_scope(&mut self,
3192 namespace: Namespace)
3195 let module = self.current_module.clone();
3196 match self.resolve_item_in_lexical_scope(module, name, namespace) {
3197 Success((target, _)) => {
3198 match target.binding.def() {
3200 // This can happen if we were looking for a type and
3201 // found a module instead. Modules don't have defs.
3202 debug!("(resolving item path by identifier in lexical scope) failed to \
3203 resolve {} after success...",
3208 debug!("(resolving item path in lexical scope) resolved `{}` to item",
3210 // This lookup is "all public" because it only searched
3211 // for one identifier in the current module (couldn't
3212 // have passed through reexports or anything like that.
3218 panic!("unexpected indeterminate result");
3221 debug!("(resolving item path by identifier in lexical scope) failed to resolve {}",
3224 if let Some((span, msg)) = err {
3225 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg))
3233 fn with_no_errors<T, F>(&mut self, f: F) -> T
3234 where F: FnOnce(&mut Resolver) -> T
3236 self.emit_errors = false;
3238 self.emit_errors = true;
3242 fn find_fallback_in_self_type(&mut self, name: Name) -> FallbackSuggestion {
3243 fn extract_path_and_node_id(t: &Ty,
3244 allow: FallbackChecks)
3245 -> Option<(Path, NodeId, FallbackChecks)> {
3247 TyPath(None, ref path) => Some((path.clone(), t.id, allow)),
3248 TyPtr(ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, OnlyTraitAndStatics),
3249 TyRptr(_, ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, allow),
3250 // This doesn't handle the remaining `Ty` variants as they are not
3251 // that commonly the self_type, it might be interesting to provide
3252 // support for those in future.
3257 fn get_module(this: &mut Resolver,
3259 name_path: &[ast::Name])
3260 -> Option<Rc<Module>> {
3261 let root = this.current_module.clone();
3262 let last_name = name_path.last().unwrap();
3264 if name_path.len() == 1 {
3265 match this.primitive_type_table.primitive_types.get(last_name) {
3268 match this.current_module.children.borrow().get(last_name) {
3269 Some(child) => child.type_ns.module(),
3275 match this.resolve_module_path(root,
3280 Success((module, _)) => Some(module),
3286 fn is_static_method(this: &Resolver, did: DefId) -> bool {
3287 if let Some(node_id) = this.ast_map.as_local_node_id(did) {
3288 let sig = match this.ast_map.get(node_id) {
3289 hir_map::NodeTraitItem(trait_item) => match trait_item.node {
3290 hir::MethodTraitItem(ref sig, _) => sig,
3293 hir_map::NodeImplItem(impl_item) => match impl_item.node {
3294 hir::ImplItemKind::Method(ref sig, _) => sig,
3299 sig.explicit_self.node == hir::SelfStatic
3301 csearch::is_static_method(&this.session.cstore, did)
3305 let (path, node_id, allowed) = match self.current_self_type {
3306 Some(ref ty) => match extract_path_and_node_id(ty, Everything) {
3308 None => return NoSuggestion,
3310 None => return NoSuggestion,
3313 if allowed == Everything {
3314 // Look for a field with the same name in the current self_type.
3315 match self.def_map.borrow().get(&node_id).map(|d| d.full_def()) {
3316 Some(DefTy(did, _)) |
3317 Some(DefStruct(did)) |
3318 Some(DefVariant(_, did, _)) => match self.structs.get(&did) {
3321 if fields.iter().any(|&field_name| name == field_name) {
3326 _ => {} // Self type didn't resolve properly
3330 let name_path = path.segments.iter().map(|seg| seg.identifier.name).collect::<Vec<_>>();
3332 // Look for a method in the current self type's impl module.
3333 if let Some(module) = get_module(self, path.span, &name_path) {
3334 if let Some(binding) = module.children.borrow().get(&name) {
3335 if let Some(DefMethod(did)) = binding.value_ns.def() {
3336 if is_static_method(self, did) {
3337 return StaticMethod(path_names_to_string(&path, 0));
3339 if self.current_trait_ref.is_some() {
3341 } else if allowed == Everything {
3348 // Look for a method in the current trait.
3349 if let Some((trait_did, ref trait_ref)) = self.current_trait_ref {
3350 if let Some(&did) = self.trait_item_map.get(&(name, trait_did)) {
3351 if is_static_method(self, did) {
3352 return TraitMethod(path_names_to_string(&trait_ref.path, 0));
3362 fn find_best_match_for_name(&mut self, name: &str) -> SuggestionType {
3363 let mut maybes: Vec<token::InternedString> = Vec::new();
3364 let mut values: Vec<usize> = Vec::new();
3366 if let Some(macro_name) = self.session.available_macros
3367 .borrow().iter().find(|n| n.as_str() == name) {
3368 return SuggestionType::Macro(format!("{}!", macro_name));
3371 for rib in self.value_ribs.iter().rev() {
3372 for (&k, _) in &rib.bindings {
3373 maybes.push(k.as_str());
3374 values.push(usize::MAX);
3378 let mut smallest = 0;
3379 for (i, other) in maybes.iter().enumerate() {
3380 values[i] = lev_distance(name, &other);
3382 if values[i] <= values[smallest] {
3387 // As a loose rule to avoid obviously incorrect suggestions, clamp the
3388 // maximum edit distance we will accept for a suggestion to one third of
3389 // the typo'd name's length.
3390 let max_distance = std::cmp::max(name.len(), 3) / 3;
3392 if !values.is_empty() && values[smallest] <= max_distance && name != &maybes[smallest][..] {
3394 SuggestionType::Function(maybes[smallest].to_string())
3397 SuggestionType::NotFound
3401 fn resolve_expr(&mut self, expr: &Expr) {
3402 // First, record candidate traits for this expression if it could
3403 // result in the invocation of a method call.
3405 self.record_candidate_traits_for_expr_if_necessary(expr);
3407 // Next, resolve the node.
3409 ExprPath(ref maybe_qself, ref path) => {
3410 let resolution = match self.resolve_possibly_assoc_item(expr.id,
3411 maybe_qself.as_ref(),
3415 // `<T>::a::b::c` is resolved by typeck alone.
3416 TypecheckRequired => {
3417 let method_name = path.segments.last().unwrap().identifier.name;
3418 let traits = self.get_traits_containing_item(method_name);
3419 self.trait_map.insert(expr.id, traits);
3420 intravisit::walk_expr(self, expr);
3423 ResolveAttempt(resolution) => resolution,
3426 // This is a local path in the value namespace. Walk through
3427 // scopes looking for it.
3428 if let Some(path_res) = resolution {
3429 // Check if struct variant
3430 if let DefVariant(_, _, true) = path_res.base_def {
3431 let path_name = path_names_to_string(path, 0);
3435 ResolutionError::StructVariantUsedAsFunction(&*path_name));
3437 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3439 if self.emit_errors {
3440 self.session.fileline_help(expr.span, &msg);
3442 self.session.span_help(expr.span, &msg);
3445 // Write the result into the def map.
3446 debug!("(resolving expr) resolved `{}`",
3447 path_names_to_string(path, 0));
3449 // Partial resolutions will need the set of traits in scope,
3450 // so they can be completed during typeck.
3451 if path_res.depth != 0 {
3452 let method_name = path.segments.last().unwrap().identifier.name;
3453 let traits = self.get_traits_containing_item(method_name);
3454 self.trait_map.insert(expr.id, traits);
3457 self.record_def(expr.id, path_res);
3460 // Be helpful if the name refers to a struct
3461 // (The pattern matching def_tys where the id is in self.structs
3462 // matches on regular structs while excluding tuple- and enum-like
3463 // structs, which wouldn't result in this error.)
3464 let path_name = path_names_to_string(path, 0);
3465 let type_res = self.with_no_errors(|this| {
3466 this.resolve_path(expr.id, path, 0, TypeNS, false)
3468 match type_res.map(|r| r.base_def) {
3469 Some(DefTy(struct_id, _)) if self.structs.contains_key(&struct_id) => {
3473 ResolutionError::StructVariantUsedAsFunction(
3477 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3479 if self.emit_errors {
3480 self.session.fileline_help(expr.span, &msg);
3482 self.session.span_help(expr.span, &msg);
3486 // Keep reporting some errors even if they're ignored above.
3487 self.resolve_path(expr.id, path, 0, ValueNS, true);
3489 let mut method_scope = false;
3490 self.value_ribs.iter().rev().all(|rib| {
3491 method_scope = match rib.kind {
3492 MethodRibKind => true,
3493 ItemRibKind | ConstantItemRibKind => false,
3494 _ => return true, // Keep advancing
3496 false // Stop advancing
3499 if method_scope && special_names::self_.as_str() == &path_name[..] {
3502 ResolutionError::SelfNotAvailableInStaticMethod);
3504 let last_name = path.segments.last().unwrap().identifier.name;
3505 let mut msg = match self.find_fallback_in_self_type(last_name) {
3507 // limit search to 5 to reduce the number
3508 // of stupid suggestions
3509 match self.find_best_match_for_name(&path_name) {
3510 SuggestionType::Macro(s) => {
3511 format!("the macro `{}`", s)
3513 SuggestionType::Function(s) => format!("`{}`", s),
3514 SuggestionType::NotFound => "".to_string(),
3517 Field => format!("`self.{}`", path_name),
3519 TraitItem => format!("to call `self.{}`", path_name),
3520 TraitMethod(path_str) |
3521 StaticMethod(path_str) =>
3522 format!("to call `{}::{}`", path_str, path_name),
3525 if !msg.is_empty() {
3526 msg = format!(". Did you mean {}?", msg)
3531 ResolutionError::UnresolvedName(&*path_name, &*msg));
3537 intravisit::walk_expr(self, expr);
3540 ExprStruct(ref path, _, _) => {
3541 // Resolve the path to the structure it goes to. We don't
3542 // check to ensure that the path is actually a structure; that
3543 // is checked later during typeck.
3544 match self.resolve_path(expr.id, path, 0, TypeNS, false) {
3545 Some(definition) => self.record_def(expr.id, definition),
3547 debug!("(resolving expression) didn't find struct def",);
3551 ResolutionError::DoesNotNameAStruct(
3552 &*path_names_to_string(path, 0))
3557 intravisit::walk_expr(self, expr);
3560 ExprLoop(_, Some(label)) | ExprWhile(_, _, Some(label)) => {
3561 self.with_label_rib(|this| {
3562 let def_like = DlDef(DefLabel(expr.id));
3565 let rib = this.label_ribs.last_mut().unwrap();
3566 let renamed = mtwt::resolve(label);
3567 rib.bindings.insert(renamed, def_like);
3570 intravisit::walk_expr(this, expr);
3574 ExprBreak(Some(label)) | ExprAgain(Some(label)) => {
3575 let renamed = mtwt::resolve(label.node);
3576 match self.search_label(renamed) {
3580 ResolutionError::UndeclaredLabel(&label.node.name.as_str()))
3582 Some(DlDef(def @ DefLabel(_))) => {
3583 // Since this def is a label, it is never read.
3584 self.record_def(expr.id,
3587 last_private: LastMod(AllPublic),
3592 self.session.span_bug(expr.span, "label wasn't mapped to a label def!")
3598 intravisit::walk_expr(self, expr);
3603 fn record_candidate_traits_for_expr_if_necessary(&mut self, expr: &Expr) {
3605 ExprField(_, name) => {
3606 // FIXME(#6890): Even though you can't treat a method like a
3607 // field, we need to add any trait methods we find that match
3608 // the field name so that we can do some nice error reporting
3609 // later on in typeck.
3610 let traits = self.get_traits_containing_item(name.node);
3611 self.trait_map.insert(expr.id, traits);
3613 ExprMethodCall(name, _, _) => {
3614 debug!("(recording candidate traits for expr) recording traits for {}",
3616 let traits = self.get_traits_containing_item(name.node);
3617 self.trait_map.insert(expr.id, traits);
3625 fn get_traits_containing_item(&mut self, name: Name) -> Vec<DefId> {
3626 debug!("(getting traits containing item) looking for '{}'", name);
3628 fn add_trait_info(found_traits: &mut Vec<DefId>, trait_def_id: DefId, name: Name) {
3629 debug!("(adding trait info) found trait {:?} for method '{}'",
3632 found_traits.push(trait_def_id);
3635 let mut found_traits = Vec::new();
3636 let mut search_module = self.current_module.clone();
3638 // Look for the current trait.
3639 match self.current_trait_ref {
3640 Some((trait_def_id, _)) => {
3641 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3642 add_trait_info(&mut found_traits, trait_def_id, name);
3645 None => {} // Nothing to do.
3648 // Look for trait children.
3649 build_reduced_graph::populate_module_if_necessary(self, &search_module);
3652 for (_, child_names) in search_module.children.borrow().iter() {
3653 let def = match child_names.type_ns.def() {
3657 let trait_def_id = match def {
3658 DefTrait(trait_def_id) => trait_def_id,
3661 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3662 add_trait_info(&mut found_traits, trait_def_id, name);
3667 // Look for imports.
3668 for (_, import) in search_module.import_resolutions.borrow().iter() {
3669 let target = match import.target_for_namespace(TypeNS) {
3671 Some(target) => target,
3673 let did = match target.binding.def() {
3674 Some(DefTrait(trait_def_id)) => trait_def_id,
3675 Some(..) | None => continue,
3677 if self.trait_item_map.contains_key(&(name, did)) {
3678 add_trait_info(&mut found_traits, did, name);
3679 let id = import.type_id;
3680 self.used_imports.insert((id, TypeNS));
3681 let trait_name = self.get_trait_name(did);
3682 self.record_import_use(id, trait_name);
3683 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
3684 self.used_crates.insert(kid);
3689 match search_module.parent_link.clone() {
3690 NoParentLink | ModuleParentLink(..) => break,
3691 BlockParentLink(parent_module, _) => {
3692 search_module = parent_module.upgrade().unwrap();
3700 fn record_def(&mut self, node_id: NodeId, resolution: PathResolution) {
3701 debug!("(recording def) recording {:?} for {}", resolution, node_id);
3702 assert!(match resolution.last_private {
3703 LastImport{..} => false,
3706 "Import should only be used for `use` directives");
3708 if let Some(prev_res) = self.def_map.borrow_mut().insert(node_id, resolution) {
3709 let span = self.ast_map.opt_span(node_id).unwrap_or(codemap::DUMMY_SP);
3710 self.session.span_bug(span,
3711 &format!("path resolved multiple times ({:?} before, {:?} now)",
3717 fn enforce_default_binding_mode(&mut self,
3719 pat_binding_mode: BindingMode,
3721 match pat_binding_mode {
3722 BindByValue(_) => {}
3726 ResolutionError::CannotUseRefBindingModeWith(descr));
3734 // Diagnostics are not particularly efficient, because they're rarely
3738 #[allow(dead_code)] // useful for debugging
3739 fn dump_module(&mut self, module_: Rc<Module>) {
3740 debug!("Dump of module `{}`:", module_to_string(&*module_));
3742 debug!("Children:");
3743 build_reduced_graph::populate_module_if_necessary(self, &module_);
3744 for (&name, _) in module_.children.borrow().iter() {
3745 debug!("* {}", name);
3748 debug!("Import resolutions:");
3749 let import_resolutions = module_.import_resolutions.borrow();
3750 for (&name, import_resolution) in import_resolutions.iter() {
3752 match import_resolution.target_for_namespace(ValueNS) {
3754 value_repr = "".to_string();
3757 value_repr = " value:?".to_string();
3763 match import_resolution.target_for_namespace(TypeNS) {
3765 type_repr = "".to_string();
3768 type_repr = " type:?".to_string();
3773 debug!("* {}:{}{}", name, value_repr, type_repr);
3779 fn names_to_string(names: &[Name]) -> String {
3780 let mut first = true;
3781 let mut result = String::new();
3786 result.push_str("::")
3788 result.push_str(&name.as_str());
3793 fn path_names_to_string(path: &Path, depth: usize) -> String {
3794 let names: Vec<ast::Name> = path.segments[..path.segments.len() - depth]
3796 .map(|seg| seg.identifier.name)
3798 names_to_string(&names[..])
3801 /// A somewhat inefficient routine to obtain the name of a module.
3802 fn module_to_string(module: &Module) -> String {
3803 let mut names = Vec::new();
3805 fn collect_mod(names: &mut Vec<ast::Name>, module: &Module) {
3806 match module.parent_link {
3808 ModuleParentLink(ref module, name) => {
3810 collect_mod(names, &*module.upgrade().unwrap());
3812 BlockParentLink(ref module, _) => {
3813 // danger, shouldn't be ident?
3814 names.push(special_idents::opaque.name);
3815 collect_mod(names, &*module.upgrade().unwrap());
3819 collect_mod(&mut names, module);
3821 if names.is_empty() {
3822 return "???".to_string();
3824 names_to_string(&names.into_iter().rev().collect::<Vec<ast::Name>>())
3828 pub struct CrateMap {
3829 pub def_map: RefCell<DefMap>,
3830 pub freevars: FreevarMap,
3831 pub export_map: ExportMap,
3832 pub trait_map: TraitMap,
3833 pub external_exports: ExternalExports,
3834 pub glob_map: Option<GlobMap>,
3837 #[derive(PartialEq,Copy, Clone)]
3838 pub enum MakeGlobMap {
3843 /// Entry point to crate resolution.
3844 pub fn resolve_crate<'a, 'tcx>(session: &'a Session,
3845 ast_map: &'a hir_map::Map<'tcx>,
3846 make_glob_map: MakeGlobMap)
3848 let krate = ast_map.krate();
3849 let mut resolver = create_resolver(session, ast_map, krate, make_glob_map, None);
3851 resolver.resolve_crate(krate);
3852 session.abort_if_errors();
3854 check_unused::check_crate(&mut resolver, krate);
3857 def_map: resolver.def_map,
3858 freevars: resolver.freevars,
3859 export_map: resolver.export_map,
3860 trait_map: resolver.trait_map,
3861 external_exports: resolver.external_exports,
3862 glob_map: if resolver.make_glob_map {
3863 Some(resolver.glob_map)
3870 /// Builds a name resolution walker to be used within this module,
3871 /// or used externally, with an optional callback function.
3873 /// The callback takes a &mut bool which allows callbacks to end a
3874 /// walk when set to true, passing through the rest of the walk, while
3875 /// preserving the ribs + current module. This allows resolve_path
3876 /// calls to be made with the correct scope info. The node in the
3877 /// callback corresponds to the current node in the walk.
3878 pub fn create_resolver<'a, 'tcx>(session: &'a Session,
3879 ast_map: &'a hir_map::Map<'tcx>,
3881 make_glob_map: MakeGlobMap,
3882 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>)
3883 -> Resolver<'a, 'tcx> {
3884 let mut resolver = Resolver::new(session, ast_map, make_glob_map);
3886 resolver.callback = callback;
3888 build_reduced_graph::build_reduced_graph(&mut resolver, krate);
3889 session.abort_if_errors();
3891 resolve_imports::resolve_imports(&mut resolver);
3892 session.abort_if_errors();
3894 record_exports::record(&mut resolver);
3895 session.abort_if_errors();
3900 __build_diagnostic_array! { librustc_resolve, DIAGNOSTICS }