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 #![crate_name = "rustc_resolve"]
12 #![unstable(feature = "rustc_private", issue = "27812")]
13 #![crate_type = "dylib"]
14 #![crate_type = "rlib"]
15 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
16 html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
17 html_root_url = "https://doc.rust-lang.org/nightly/")]
19 #![feature(associated_consts)]
20 #![feature(borrow_state)]
21 #![feature(rustc_diagnostic_macros)]
22 #![feature(rustc_private)]
23 #![feature(staged_api)]
31 extern crate rustc_bitflags;
32 extern crate rustc_front;
35 use self::PatternBindingMode::*;
36 use self::Namespace::*;
37 use self::NamespaceResult::*;
38 use self::ResolveResult::*;
39 use self::FallbackSuggestion::*;
40 use self::TypeParameters::*;
42 use self::UseLexicalScopeFlag::*;
43 use self::ModulePrefixResult::*;
44 use self::AssocItemResolveResult::*;
45 use self::NameSearchType::*;
46 use self::BareIdentifierPatternResolution::*;
47 use self::ParentLink::*;
48 use self::FallbackChecks::*;
50 use rustc::front::map as hir_map;
51 use rustc::session::Session;
53 use rustc::middle::cstore::{CrateStore, DefLike, DlDef};
54 use rustc::middle::def::*;
55 use rustc::middle::def_id::DefId;
56 use rustc::middle::pat_util::pat_bindings;
57 use rustc::middle::privacy::*;
58 use rustc::middle::subst::{ParamSpace, FnSpace, TypeSpace};
59 use rustc::middle::ty::{Freevar, FreevarMap, TraitMap, GlobMap};
60 use rustc::util::nodemap::{NodeMap, DefIdSet, FnvHashMap};
63 use syntax::ast::{CRATE_NODE_ID, Name, NodeId, CrateNum, TyIs, TyI8, TyI16, TyI32, TyI64};
64 use syntax::ast::{TyUs, TyU8, TyU16, TyU32, TyU64, TyF64, TyF32};
65 use syntax::attr::AttrMetaMethods;
66 use syntax::codemap::{self, Span, Pos};
67 use syntax::errors::DiagnosticBuilder;
68 use syntax::parse::token::{self, special_names, special_idents};
69 use syntax::util::lev_distance::find_best_match_for_name;
71 use rustc_front::intravisit::{self, FnKind, Visitor};
73 use rustc_front::hir::{Arm, BindByRef, BindByValue, BindingMode, Block};
74 use rustc_front::hir::Crate;
75 use rustc_front::hir::{Expr, ExprAgain, ExprBreak, ExprCall, ExprField};
76 use rustc_front::hir::{ExprLoop, ExprWhile, ExprMethodCall};
77 use rustc_front::hir::{ExprPath, ExprStruct, FnDecl};
78 use rustc_front::hir::{ForeignItemFn, ForeignItemStatic, Generics};
79 use rustc_front::hir::{ImplItem, Item, ItemConst, ItemEnum, ItemExternCrate};
80 use rustc_front::hir::{ItemFn, ItemForeignMod, ItemImpl, ItemMod, ItemStatic, ItemDefaultImpl};
81 use rustc_front::hir::{ItemStruct, ItemTrait, ItemTy, ItemUse};
82 use rustc_front::hir::Local;
83 use rustc_front::hir::{Pat, PatEnum, PatIdent, PatLit, PatQPath};
84 use rustc_front::hir::{PatRange, PatStruct, Path, PrimTy};
85 use rustc_front::hir::{TraitRef, Ty, TyBool, TyChar, TyFloat, TyInt};
86 use rustc_front::hir::{TyRptr, TyStr, TyUint, TyPath, TyPtr};
87 use rustc_front::util::walk_pat;
89 use std::collections::{HashMap, HashSet};
90 use std::cell::{Cell, RefCell};
92 use std::mem::replace;
93 use std::rc::{Rc, Weak};
95 use resolve_imports::{Target, ImportDirective, ImportResolutionPerNamespace};
96 use resolve_imports::Shadowable;
98 // NB: This module needs to be declared first so diagnostics are
99 // registered before they are used.
104 mod build_reduced_graph;
107 // Perform the callback, not walking deeper if the return is true
108 macro_rules! execute_callback {
109 ($node: expr, $walker: expr) => (
110 if let Some(ref callback) = $walker.callback {
111 if callback($node, &mut $walker.resolved) {
118 enum SuggestionType {
120 Function(token::InternedString),
124 pub enum ResolutionError<'a> {
125 /// error E0260: name conflicts with an extern crate
126 NameConflictsWithExternCrate(Name),
127 /// error E0401: can't use type parameters from outer function
128 TypeParametersFromOuterFunction,
129 /// error E0402: cannot use an outer type parameter in this context
130 OuterTypeParameterContext,
131 /// error E0403: the name is already used for a type parameter in this type parameter list
132 NameAlreadyUsedInTypeParameterList(Name),
133 /// error E0404: is not a trait
134 IsNotATrait(&'a str),
135 /// error E0405: use of undeclared trait name
136 UndeclaredTraitName(&'a str),
137 /// error E0406: undeclared associated type
138 UndeclaredAssociatedType,
139 /// error E0407: method is not a member of trait
140 MethodNotMemberOfTrait(Name, &'a str),
141 /// error E0437: type is not a member of trait
142 TypeNotMemberOfTrait(Name, &'a str),
143 /// error E0438: const is not a member of trait
144 ConstNotMemberOfTrait(Name, &'a str),
145 /// error E0408: variable `{}` from pattern #1 is not bound in pattern
146 VariableNotBoundInPattern(Name, usize),
147 /// error E0409: variable is bound with different mode in pattern #{} than in pattern #1
148 VariableBoundWithDifferentMode(Name, usize),
149 /// error E0410: variable from pattern is not bound in pattern #1
150 VariableNotBoundInParentPattern(Name, usize),
151 /// error E0411: use of `Self` outside of an impl or trait
152 SelfUsedOutsideImplOrTrait,
153 /// error E0412: use of undeclared
154 UseOfUndeclared(&'a str, &'a str),
155 /// error E0413: declaration shadows an enum variant or unit-like struct in scope
156 DeclarationShadowsEnumVariantOrUnitLikeStruct(Name),
157 /// error E0414: only irrefutable patterns allowed here
158 OnlyIrrefutablePatternsAllowedHere(DefId, Name),
159 /// error E0415: identifier is bound more than once in this parameter list
160 IdentifierBoundMoreThanOnceInParameterList(&'a str),
161 /// error E0416: identifier is bound more than once in the same pattern
162 IdentifierBoundMoreThanOnceInSamePattern(&'a str),
163 /// error E0417: static variables cannot be referenced in a pattern
164 StaticVariableReference,
165 /// error E0418: is not an enum variant, struct or const
166 NotAnEnumVariantStructOrConst(&'a str),
167 /// error E0419: unresolved enum variant, struct or const
168 UnresolvedEnumVariantStructOrConst(&'a str),
169 /// error E0420: is not an associated const
170 NotAnAssociatedConst(&'a str),
171 /// error E0421: unresolved associated const
172 UnresolvedAssociatedConst(&'a str),
173 /// error E0422: does not name a struct
174 DoesNotNameAStruct(&'a str),
175 /// error E0423: is a struct variant name, but this expression uses it like a function name
176 StructVariantUsedAsFunction(&'a str),
177 /// error E0424: `self` is not available in a static method
178 SelfNotAvailableInStaticMethod,
179 /// error E0425: unresolved name
180 UnresolvedName(&'a str, &'a str, UnresolvedNameContext),
181 /// error E0426: use of undeclared label
182 UndeclaredLabel(&'a str),
183 /// error E0427: cannot use `ref` binding mode with ...
184 CannotUseRefBindingModeWith(&'a str),
185 /// error E0428: duplicate definition
186 DuplicateDefinition(&'a str, Name),
187 /// error E0429: `self` imports are only allowed within a { } list
188 SelfImportsOnlyAllowedWithin,
189 /// error E0430: `self` import can only appear once in the list
190 SelfImportCanOnlyAppearOnceInTheList,
191 /// error E0431: `self` import can only appear in an import list with a non-empty prefix
192 SelfImportOnlyInImportListWithNonEmptyPrefix,
193 /// error E0432: unresolved import
194 UnresolvedImport(Option<(&'a str, &'a str)>),
195 /// error E0433: failed to resolve
196 FailedToResolve(&'a str),
197 /// error E0434: can't capture dynamic environment in a fn item
198 CannotCaptureDynamicEnvironmentInFnItem,
199 /// error E0435: attempt to use a non-constant value in a constant
200 AttemptToUseNonConstantValueInConstant,
203 /// Context of where `ResolutionError::UnresolvedName` arose.
204 #[derive(Clone, PartialEq, Eq, Debug)]
205 pub enum UnresolvedNameContext {
206 /// `PathIsMod(id)` indicates that a given path, used in
207 /// expression context, actually resolved to a module rather than
208 /// a value. The `id` attached to the variant is the node id of
209 /// the erroneous path expression.
210 PathIsMod(ast::NodeId),
212 /// `Other` means we have no extra information about the context
213 /// of the unresolved name error. (Maybe we could eliminate all
214 /// such cases; but for now, this is an information-free default.)
218 fn resolve_error<'b, 'a: 'b, 'tcx: 'a>(resolver: &'b Resolver<'a, 'tcx>,
219 span: syntax::codemap::Span,
220 resolution_error: ResolutionError<'b>) {
221 resolve_struct_error(resolver, span, resolution_error).emit();
224 fn resolve_struct_error<'b, 'a: 'b, 'tcx: 'a>(resolver: &'b Resolver<'a, 'tcx>,
225 span: syntax::codemap::Span,
226 resolution_error: ResolutionError<'b>)
227 -> DiagnosticBuilder<'a> {
228 if !resolver.emit_errors {
229 return resolver.session.diagnostic().struct_dummy();
232 match resolution_error {
233 ResolutionError::NameConflictsWithExternCrate(name) => {
234 struct_span_err!(resolver.session,
237 "the name `{}` conflicts with an external crate \
238 that has been imported into this module",
241 ResolutionError::TypeParametersFromOuterFunction => {
242 struct_span_err!(resolver.session,
245 "can't use type parameters from outer function; try using a local \
246 type parameter instead")
248 ResolutionError::OuterTypeParameterContext => {
249 struct_span_err!(resolver.session,
252 "cannot use an outer type parameter in this context")
254 ResolutionError::NameAlreadyUsedInTypeParameterList(name) => {
255 struct_span_err!(resolver.session,
258 "the name `{}` is already used for a type parameter in this type \
262 ResolutionError::IsNotATrait(name) => {
263 struct_span_err!(resolver.session, span, E0404, "`{}` is not a trait", name)
265 ResolutionError::UndeclaredTraitName(name) => {
266 struct_span_err!(resolver.session,
269 "use of undeclared trait name `{}`",
272 ResolutionError::UndeclaredAssociatedType => {
273 struct_span_err!(resolver.session, span, E0406, "undeclared associated type")
275 ResolutionError::MethodNotMemberOfTrait(method, trait_) => {
276 struct_span_err!(resolver.session,
279 "method `{}` is not a member of trait `{}`",
283 ResolutionError::TypeNotMemberOfTrait(type_, trait_) => {
284 struct_span_err!(resolver.session,
287 "type `{}` is not a member of trait `{}`",
291 ResolutionError::ConstNotMemberOfTrait(const_, trait_) => {
292 struct_span_err!(resolver.session,
295 "const `{}` is not a member of trait `{}`",
299 ResolutionError::VariableNotBoundInPattern(variable_name, pattern_number) => {
300 struct_span_err!(resolver.session,
303 "variable `{}` from pattern #1 is not bound in pattern #{}",
307 ResolutionError::VariableBoundWithDifferentMode(variable_name, pattern_number) => {
308 struct_span_err!(resolver.session,
311 "variable `{}` is bound with different mode in pattern #{} than in \
316 ResolutionError::VariableNotBoundInParentPattern(variable_name, pattern_number) => {
317 struct_span_err!(resolver.session,
320 "variable `{}` from pattern #{} is not bound in pattern #1",
324 ResolutionError::SelfUsedOutsideImplOrTrait => {
325 struct_span_err!(resolver.session,
328 "use of `Self` outside of an impl or trait")
330 ResolutionError::UseOfUndeclared(kind, name) => {
331 struct_span_err!(resolver.session,
334 "use of undeclared {} `{}`",
338 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(name) => {
339 struct_span_err!(resolver.session,
342 "declaration of `{}` shadows an enum variant \
343 or unit-like struct in scope",
346 ResolutionError::OnlyIrrefutablePatternsAllowedHere(did, name) => {
347 let mut err = struct_span_err!(resolver.session,
350 "only irrefutable patterns allowed here");
352 "there already is a constant in scope sharing the same \
353 name as this pattern");
354 if let Some(sp) = resolver.ast_map.span_if_local(did) {
355 err.span_note(sp, "constant defined here");
357 if let Some(directive) = resolver.current_module
361 let item = resolver.ast_map.expect_item(directive.value_ns.id);
362 err.span_note(item.span, "constant imported here");
366 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(identifier) => {
367 struct_span_err!(resolver.session,
370 "identifier `{}` is bound more than once in this parameter list",
373 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(identifier) => {
374 struct_span_err!(resolver.session,
377 "identifier `{}` is bound more than once in the same pattern",
380 ResolutionError::StaticVariableReference => {
381 struct_span_err!(resolver.session,
384 "static variables cannot be referenced in a pattern, use a \
387 ResolutionError::NotAnEnumVariantStructOrConst(name) => {
388 struct_span_err!(resolver.session,
391 "`{}` is not an enum variant, struct or const",
394 ResolutionError::UnresolvedEnumVariantStructOrConst(name) => {
395 struct_span_err!(resolver.session,
398 "unresolved enum variant, struct or const `{}`",
401 ResolutionError::NotAnAssociatedConst(name) => {
402 struct_span_err!(resolver.session,
405 "`{}` is not an associated const",
408 ResolutionError::UnresolvedAssociatedConst(name) => {
409 struct_span_err!(resolver.session,
412 "unresolved associated const `{}`",
415 ResolutionError::DoesNotNameAStruct(name) => {
416 struct_span_err!(resolver.session,
419 "`{}` does not name a structure",
422 ResolutionError::StructVariantUsedAsFunction(path_name) => {
423 struct_span_err!(resolver.session,
426 "`{}` is the name of a struct or struct variant, but this expression \
427 uses it like a function name",
430 ResolutionError::SelfNotAvailableInStaticMethod => {
431 struct_span_err!(resolver.session,
434 "`self` is not available in a static method. Maybe a `self` \
435 argument is missing?")
437 ResolutionError::UnresolvedName(path, msg, context) => {
438 let mut err = struct_span_err!(resolver.session,
441 "unresolved name `{}`{}",
446 UnresolvedNameContext::Other => { } // no help available
447 UnresolvedNameContext::PathIsMod(id) => {
448 let mut help_msg = String::new();
449 let parent_id = resolver.ast_map.get_parent_node(id);
450 if let Some(hir_map::Node::NodeExpr(e)) = resolver.ast_map.find(parent_id) {
452 ExprField(_, ident) => {
453 help_msg = format!("To reference an item from the \
454 `{module}` module, use \
455 `{module}::{ident}`",
459 ExprMethodCall(ident, _, _) => {
460 help_msg = format!("To call a function from the \
461 `{module}` module, use \
462 `{module}::{ident}(..)`",
467 help_msg = format!("No function corresponds to `{module}(..)`",
470 _ => { } // no help available
473 help_msg = format!("Module `{module}` cannot be the value of an expression",
477 if !help_msg.is_empty() {
478 err.fileline_help(span, &help_msg);
484 ResolutionError::UndeclaredLabel(name) => {
485 struct_span_err!(resolver.session,
488 "use of undeclared label `{}`",
491 ResolutionError::CannotUseRefBindingModeWith(descr) => {
492 struct_span_err!(resolver.session,
495 "cannot use `ref` binding mode with {}",
498 ResolutionError::DuplicateDefinition(namespace, name) => {
499 struct_span_err!(resolver.session,
502 "duplicate definition of {} `{}`",
506 ResolutionError::SelfImportsOnlyAllowedWithin => {
507 struct_span_err!(resolver.session,
511 "`self` imports are only allowed within a { } list")
513 ResolutionError::SelfImportCanOnlyAppearOnceInTheList => {
514 struct_span_err!(resolver.session,
517 "`self` import can only appear once in the list")
519 ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix => {
520 struct_span_err!(resolver.session,
523 "`self` import can only appear in an import list with a \
526 ResolutionError::UnresolvedImport(name) => {
527 let msg = match name {
528 Some((n, p)) => format!("unresolved import `{}`{}", n, p),
529 None => "unresolved import".to_owned(),
531 struct_span_err!(resolver.session, span, E0432, "{}", msg)
533 ResolutionError::FailedToResolve(msg) => {
534 struct_span_err!(resolver.session, span, E0433, "failed to resolve. {}", msg)
536 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem => {
537 struct_span_err!(resolver.session,
541 "can't capture dynamic environment in a fn item; use the || { ... } \
542 closure form instead")
544 ResolutionError::AttemptToUseNonConstantValueInConstant => {
545 struct_span_err!(resolver.session,
548 "attempt to use a non-constant value in a constant")
553 #[derive(Copy, Clone)]
556 binding_mode: BindingMode,
559 // Map from the name in a pattern to its binding mode.
560 type BindingMap = HashMap<Name, BindingInfo>;
562 #[derive(Copy, Clone, PartialEq)]
563 enum PatternBindingMode {
565 LocalIrrefutableMode,
566 ArgumentIrrefutableMode,
569 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
575 /// A NamespaceResult represents the result of resolving an import in
576 /// a particular namespace. The result is either definitely-resolved,
577 /// definitely- unresolved, or unknown.
579 enum NamespaceResult {
580 /// Means that resolve hasn't gathered enough information yet to determine
581 /// whether the name is bound in this namespace. (That is, it hasn't
582 /// resolved all `use` directives yet.)
584 /// Means that resolve has determined that the name is definitely
585 /// not bound in the namespace.
587 /// Means that resolve has determined that the name is bound in the Module
588 /// argument, and specified by the NameBinding argument.
589 BoundResult(Rc<Module>, NameBinding),
592 impl NamespaceResult {
593 fn is_unknown(&self) -> bool {
595 UnknownResult => true,
599 fn is_unbound(&self) -> bool {
601 UnboundResult => true,
607 impl<'a, 'v, 'tcx> Visitor<'v> for Resolver<'a, 'tcx> {
608 fn visit_nested_item(&mut self, item: hir::ItemId) {
609 self.visit_item(self.ast_map.expect_item(item.id))
611 fn visit_item(&mut self, item: &Item) {
612 execute_callback!(hir_map::Node::NodeItem(item), self);
613 self.resolve_item(item);
615 fn visit_arm(&mut self, arm: &Arm) {
616 self.resolve_arm(arm);
618 fn visit_block(&mut self, block: &Block) {
619 execute_callback!(hir_map::Node::NodeBlock(block), self);
620 self.resolve_block(block);
622 fn visit_expr(&mut self, expr: &Expr) {
623 execute_callback!(hir_map::Node::NodeExpr(expr), self);
624 self.resolve_expr(expr);
626 fn visit_local(&mut self, local: &Local) {
627 execute_callback!(hir_map::Node::NodeLocal(&*local.pat), self);
628 self.resolve_local(local);
630 fn visit_ty(&mut self, ty: &Ty) {
631 self.resolve_type(ty);
633 fn visit_generics(&mut self, generics: &Generics) {
634 self.resolve_generics(generics);
636 fn visit_poly_trait_ref(&mut self, tref: &hir::PolyTraitRef, m: &hir::TraitBoundModifier) {
637 match self.resolve_trait_reference(tref.trait_ref.ref_id, &tref.trait_ref.path, 0) {
638 Ok(def) => self.record_def(tref.trait_ref.ref_id, def),
640 // error already reported
641 self.record_def(tref.trait_ref.ref_id, err_path_resolution())
644 intravisit::walk_poly_trait_ref(self, tref, m);
646 fn visit_variant(&mut self,
647 variant: &hir::Variant,
649 item_id: ast::NodeId) {
650 execute_callback!(hir_map::Node::NodeVariant(variant), self);
651 if let Some(ref dis_expr) = variant.node.disr_expr {
652 // resolve the discriminator expr as a constant
653 self.with_constant_rib(|this| {
654 this.visit_expr(dis_expr);
658 // `intravisit::walk_variant` without the discriminant expression.
659 self.visit_variant_data(&variant.node.data,
665 fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem) {
666 execute_callback!(hir_map::Node::NodeForeignItem(foreign_item), self);
667 let type_parameters = match foreign_item.node {
668 ForeignItemFn(_, ref generics) => {
669 HasTypeParameters(generics, FnSpace, ItemRibKind)
671 ForeignItemStatic(..) => NoTypeParameters,
673 self.with_type_parameter_rib(type_parameters, |this| {
674 intravisit::walk_foreign_item(this, foreign_item);
677 fn visit_fn(&mut self,
678 function_kind: FnKind<'v>,
679 declaration: &'v FnDecl,
683 let rib_kind = match function_kind {
684 FnKind::ItemFn(_, generics, _, _, _, _) => {
685 self.visit_generics(generics);
688 FnKind::Method(_, sig, _) => {
689 self.visit_generics(&sig.generics);
690 self.visit_explicit_self(&sig.explicit_self);
693 FnKind::Closure => ClosureRibKind(node_id),
695 self.resolve_function(rib_kind, declaration, block);
699 type ErrorMessage = Option<(Span, String)>;
701 enum ResolveResult<T> {
702 Failed(ErrorMessage), // Failed to resolve the name, optional helpful error message.
703 Indeterminate, // Couldn't determine due to unresolved globs.
704 Success(T), // Successfully resolved the import.
707 impl<T> ResolveResult<T> {
708 fn success(&self) -> bool {
716 enum FallbackSuggestion {
721 StaticMethod(String),
725 #[derive(Copy, Clone)]
726 enum TypeParameters<'a> {
728 HasTypeParameters(// Type parameters.
731 // Identifies the things that these parameters
732 // were declared on (type, fn, etc)
735 // The kind of the rib used for type parameters.
739 // The rib kind controls the translation of local
740 // definitions (`DefLocal`) to upvars (`DefUpvar`).
741 #[derive(Copy, Clone, Debug)]
743 // No translation needs to be applied.
746 // We passed through a closure scope at the given node ID.
747 // Translate upvars as appropriate.
748 ClosureRibKind(NodeId /* func id */),
750 // We passed through an impl or trait and are now in one of its
751 // methods. Allow references to ty params that impl or trait
752 // binds. Disallow any other upvars (including other ty params that are
756 // We passed through an item scope. Disallow upvars.
759 // We're in a constant item. Can't refer to dynamic stuff.
763 #[derive(Copy, Clone)]
764 enum UseLexicalScopeFlag {
769 enum ModulePrefixResult {
771 PrefixFound(Rc<Module>, usize),
774 #[derive(Copy, Clone)]
775 enum AssocItemResolveResult {
776 /// Syntax such as `<T>::item`, which can't be resolved until type
779 /// We should have been able to resolve the associated item.
780 ResolveAttempt(Option<PathResolution>),
783 #[derive(Copy, Clone, PartialEq)]
784 enum NameSearchType {
785 /// We're doing a name search in order to resolve a `use` directive.
788 /// We're doing a name search in order to resolve a path type, a path
789 /// expression, or a path pattern.
793 #[derive(Copy, Clone)]
794 enum BareIdentifierPatternResolution {
795 FoundStructOrEnumVariant(Def, LastPrivate),
796 FoundConst(Def, LastPrivate, Name),
797 BareIdentifierPatternUnresolved,
803 bindings: HashMap<Name, DefLike>,
808 fn new(kind: RibKind) -> Rib {
810 bindings: HashMap::new(),
816 /// A definition along with the index of the rib it was found on
818 ribs: Option<(Namespace, usize)>,
823 fn from_def(def: Def) -> Self {
831 /// The link from a module up to its nearest parent node.
832 #[derive(Clone,Debug)]
835 ModuleParentLink(Weak<Module>, Name),
836 BlockParentLink(Weak<Module>, NodeId),
839 /// One node in the tree of modules.
841 parent_link: ParentLink,
842 def: Cell<Option<Def>>,
845 children: RefCell<HashMap<Name, NameBindings>>,
846 imports: RefCell<Vec<ImportDirective>>,
848 // The external module children of this node that were declared with
850 external_module_children: RefCell<HashMap<Name, Rc<Module>>>,
852 // The anonymous children of this node. Anonymous children are pseudo-
853 // modules that are implicitly created around items contained within
856 // For example, if we have this:
864 // There will be an anonymous module created around `g` with the ID of the
865 // entry block for `f`.
866 anonymous_children: RefCell<NodeMap<Rc<Module>>>,
868 // The status of resolving each import in this module.
869 import_resolutions: RefCell<HashMap<Name, ImportResolutionPerNamespace>>,
871 // The number of unresolved globs that this module exports.
872 glob_count: Cell<usize>,
874 // The number of unresolved pub imports (both regular and globs) in this module
875 pub_count: Cell<usize>,
877 // The number of unresolved pub glob imports in this module
878 pub_glob_count: Cell<usize>,
880 // The index of the import we're resolving.
881 resolved_import_count: Cell<usize>,
883 // Whether this module is populated. If not populated, any attempt to
884 // access the children must be preceded with a
885 // `populate_module_if_necessary` call.
886 populated: Cell<bool>,
890 fn new(parent_link: ParentLink,
896 parent_link: parent_link,
898 is_public: is_public,
899 children: RefCell::new(HashMap::new()),
900 imports: RefCell::new(Vec::new()),
901 external_module_children: RefCell::new(HashMap::new()),
902 anonymous_children: RefCell::new(NodeMap()),
903 import_resolutions: RefCell::new(HashMap::new()),
904 glob_count: Cell::new(0),
905 pub_count: Cell::new(0),
906 pub_glob_count: Cell::new(0),
907 resolved_import_count: Cell::new(0),
908 populated: Cell::new(!external),
912 fn def_id(&self) -> Option<DefId> {
913 self.def.get().as_ref().map(Def::def_id)
916 fn is_normal(&self) -> bool {
917 match self.def.get() {
918 Some(DefMod(_)) | Some(DefForeignMod(_)) => true,
923 fn is_trait(&self) -> bool {
924 match self.def.get() {
925 Some(DefTrait(_)) => true,
930 fn all_imports_resolved(&self) -> bool {
931 if self.imports.borrow_state() == ::std::cell::BorrowState::Writing {
932 // it is currently being resolved ! so nope
935 self.imports.borrow().len() == self.resolved_import_count.get()
941 pub fn inc_glob_count(&self) {
942 self.glob_count.set(self.glob_count.get() + 1);
944 pub fn dec_glob_count(&self) {
945 assert!(self.glob_count.get() > 0);
946 self.glob_count.set(self.glob_count.get() - 1);
948 pub fn inc_pub_count(&self) {
949 self.pub_count.set(self.pub_count.get() + 1);
951 pub fn dec_pub_count(&self) {
952 assert!(self.pub_count.get() > 0);
953 self.pub_count.set(self.pub_count.get() - 1);
955 pub fn inc_pub_glob_count(&self) {
956 self.pub_glob_count.set(self.pub_glob_count.get() + 1);
958 pub fn dec_pub_glob_count(&self) {
959 assert!(self.pub_glob_count.get() > 0);
960 self.pub_glob_count.set(self.pub_glob_count.get() - 1);
964 impl fmt::Debug for Module {
965 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
979 flags DefModifiers: u8 {
980 // Enum variants are always considered `PUBLIC`, this is needed for `use Enum::Variant`
981 // or `use Enum::*` to work on private enums.
982 const PUBLIC = 1 << 0,
983 const IMPORTABLE = 1 << 1,
984 // Variants are considered `PUBLIC`, but some of them live in private enums.
985 // We need to track them to prohibit reexports like `pub use PrivEnum::Variant`.
986 const PRIVATE_VARIANT = 1 << 2,
990 // Records a possibly-private value, type, or module definition.
993 modifiers: DefModifiers, // see note in ImportResolutionPerNamespace about how to use this
994 def_or_module: DefOrModule,
1005 fn create_from_module(module: Rc<Module>, span: Option<Span>) -> Self {
1006 let modifiers = if module.is_public {
1007 DefModifiers::PUBLIC
1009 DefModifiers::empty()
1010 } | DefModifiers::IMPORTABLE;
1012 NsDef { modifiers: modifiers, def_or_module: DefOrModule::Module(module), span: span }
1015 fn create_from_def(def: Def, modifiers: DefModifiers, span: Option<Span>) -> Self {
1016 NsDef { modifiers: modifiers, def_or_module: DefOrModule::Def(def), span: span }
1019 fn module(&self) -> Option<Rc<Module>> {
1020 match self.def_or_module {
1021 DefOrModule::Module(ref module) => Some(module.clone()),
1022 DefOrModule::Def(_) => None,
1026 fn def(&self) -> Option<Def> {
1027 match self.def_or_module {
1028 DefOrModule::Def(def) => Some(def),
1029 DefOrModule::Module(ref module) => module.def.get(),
1034 // Records at most one definition that a name in a namespace is bound to
1035 #[derive(Clone,Debug)]
1036 pub struct NameBinding(Rc<RefCell<Option<NsDef>>>);
1040 NameBinding(Rc::new(RefCell::new(None)))
1043 fn create_from_module(module: Rc<Module>) -> Self {
1044 NameBinding(Rc::new(RefCell::new(Some(NsDef::create_from_module(module, None)))))
1047 fn set(&self, ns_def: NsDef) {
1048 *self.0.borrow_mut() = Some(ns_def);
1051 fn set_modifiers(&self, modifiers: DefModifiers) {
1052 if let Some(ref mut ns_def) = *self.0.borrow_mut() {
1053 ns_def.modifiers = modifiers
1057 fn borrow(&self) -> ::std::cell::Ref<Option<NsDef>> {
1061 // Lifted versions of the NsDef methods and fields
1062 fn def(&self) -> Option<Def> {
1063 self.borrow().as_ref().and_then(NsDef::def)
1065 fn module(&self) -> Option<Rc<Module>> {
1066 self.borrow().as_ref().and_then(NsDef::module)
1068 fn span(&self) -> Option<Span> {
1069 self.borrow().as_ref().and_then(|def| def.span)
1071 fn modifiers(&self) -> Option<DefModifiers> {
1072 self.borrow().as_ref().and_then(|def| Some(def.modifiers))
1075 fn defined(&self) -> bool {
1076 self.borrow().is_some()
1079 fn defined_with(&self, modifiers: DefModifiers) -> bool {
1080 self.modifiers().map(|m| m.contains(modifiers)).unwrap_or(false)
1083 fn is_public(&self) -> bool {
1084 self.defined_with(DefModifiers::PUBLIC)
1087 fn def_and_lp(&self) -> (Def, LastPrivate) {
1088 let def = self.def().unwrap();
1089 (def, LastMod(if self.is_public() { AllPublic } else { DependsOn(def.def_id()) }))
1093 // Records the definitions (at most one for each namespace) that a name is
1095 #[derive(Clone,Debug)]
1096 pub struct NameBindings {
1097 type_ns: NameBinding, // < Meaning in type namespace.
1098 value_ns: NameBinding, // < Meaning in value namespace.
1101 impl ::std::ops::Index<Namespace> for NameBindings {
1102 type Output = NameBinding;
1103 fn index(&self, namespace: Namespace) -> &NameBinding {
1104 match namespace { TypeNS => &self.type_ns, ValueNS => &self.value_ns }
1109 fn new() -> NameBindings {
1111 type_ns: NameBinding::new(),
1112 value_ns: NameBinding::new(),
1116 /// Creates a new module in this set of name bindings.
1117 fn define_module(&self, module: Rc<Module>, sp: Span) {
1118 self.type_ns.set(NsDef::create_from_module(module, Some(sp)));
1121 /// Records a type definition.
1122 fn define_type(&self, def: Def, sp: Span, modifiers: DefModifiers) {
1123 debug!("defining type for def {:?} with modifiers {:?}", def, modifiers);
1124 self.type_ns.set(NsDef::create_from_def(def, modifiers, Some(sp)));
1127 /// Records a value definition.
1128 fn define_value(&self, def: Def, sp: Span, modifiers: DefModifiers) {
1129 debug!("defining value for def {:?} with modifiers {:?}", def, modifiers);
1130 self.value_ns.set(NsDef::create_from_def(def, modifiers, Some(sp)));
1134 /// Interns the names of the primitive types.
1135 struct PrimitiveTypeTable {
1136 primitive_types: HashMap<Name, PrimTy>,
1139 impl PrimitiveTypeTable {
1140 fn new() -> PrimitiveTypeTable {
1141 let mut table = PrimitiveTypeTable { primitive_types: HashMap::new() };
1143 table.intern("bool", TyBool);
1144 table.intern("char", TyChar);
1145 table.intern("f32", TyFloat(TyF32));
1146 table.intern("f64", TyFloat(TyF64));
1147 table.intern("isize", TyInt(TyIs));
1148 table.intern("i8", TyInt(TyI8));
1149 table.intern("i16", TyInt(TyI16));
1150 table.intern("i32", TyInt(TyI32));
1151 table.intern("i64", TyInt(TyI64));
1152 table.intern("str", TyStr);
1153 table.intern("usize", TyUint(TyUs));
1154 table.intern("u8", TyUint(TyU8));
1155 table.intern("u16", TyUint(TyU16));
1156 table.intern("u32", TyUint(TyU32));
1157 table.intern("u64", TyUint(TyU64));
1162 fn intern(&mut self, string: &str, primitive_type: PrimTy) {
1163 self.primitive_types.insert(token::intern(string), primitive_type);
1167 /// The main resolver class.
1168 pub struct Resolver<'a, 'tcx: 'a> {
1169 session: &'a Session,
1171 ast_map: &'a hir_map::Map<'tcx>,
1173 graph_root: Rc<Module>,
1175 trait_item_map: FnvHashMap<(Name, DefId), DefId>,
1177 structs: FnvHashMap<DefId, Vec<Name>>,
1179 // The number of imports that are currently unresolved.
1180 unresolved_imports: usize,
1182 // The module that represents the current item scope.
1183 current_module: Rc<Module>,
1185 // The current set of local scopes, for values.
1186 // FIXME #4948: Reuse ribs to avoid allocation.
1187 value_ribs: Vec<Rib>,
1189 // The current set of local scopes, for types.
1190 type_ribs: Vec<Rib>,
1192 // The current set of local scopes, for labels.
1193 label_ribs: Vec<Rib>,
1195 // The trait that the current context can refer to.
1196 current_trait_ref: Option<(DefId, TraitRef)>,
1198 // The current self type if inside an impl (used for better errors).
1199 current_self_type: Option<Ty>,
1201 // The idents for the primitive types.
1202 primitive_type_table: PrimitiveTypeTable,
1204 def_map: RefCell<DefMap>,
1205 freevars: FreevarMap,
1206 freevars_seen: NodeMap<NodeMap<usize>>,
1207 export_map: ExportMap,
1208 trait_map: TraitMap,
1209 external_exports: ExternalExports,
1211 // Whether or not to print error messages. Can be set to true
1212 // when getting additional info for error message suggestions,
1213 // so as to avoid printing duplicate errors
1216 make_glob_map: bool,
1217 // Maps imports to the names of items actually imported (this actually maps
1218 // all imports, but only glob imports are actually interesting).
1221 used_imports: HashSet<(NodeId, Namespace)>,
1222 used_crates: HashSet<CrateNum>,
1224 // Callback function for intercepting walks
1225 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>,
1226 // The intention is that the callback modifies this flag.
1227 // Once set, the resolver falls out of the walk, preserving the ribs.
1231 #[derive(PartialEq)]
1232 enum FallbackChecks {
1234 OnlyTraitAndStatics,
1237 impl<'a, 'tcx> Resolver<'a, 'tcx> {
1238 fn new(session: &'a Session,
1239 ast_map: &'a hir_map::Map<'tcx>,
1240 make_glob_map: MakeGlobMap)
1241 -> Resolver<'a, 'tcx> {
1242 let root_def_id = ast_map.local_def_id(CRATE_NODE_ID);
1243 let graph_root = Module::new(NoParentLink, Some(DefMod(root_def_id)), false, true);
1250 // The outermost module has def ID 0; this is not reflected in the
1252 graph_root: graph_root.clone(),
1254 trait_item_map: FnvHashMap(),
1255 structs: FnvHashMap(),
1257 unresolved_imports: 0,
1259 current_module: graph_root,
1260 value_ribs: Vec::new(),
1261 type_ribs: Vec::new(),
1262 label_ribs: Vec::new(),
1264 current_trait_ref: None,
1265 current_self_type: None,
1267 primitive_type_table: PrimitiveTypeTable::new(),
1269 def_map: RefCell::new(NodeMap()),
1270 freevars: NodeMap(),
1271 freevars_seen: NodeMap(),
1272 export_map: NodeMap(),
1273 trait_map: NodeMap(),
1274 used_imports: HashSet::new(),
1275 used_crates: HashSet::new(),
1276 external_exports: DefIdSet(),
1279 make_glob_map: make_glob_map == MakeGlobMap::Yes,
1280 glob_map: HashMap::new(),
1288 fn record_import_use(&mut self, import_id: NodeId, name: Name) {
1289 if !self.make_glob_map {
1292 if self.glob_map.contains_key(&import_id) {
1293 self.glob_map.get_mut(&import_id).unwrap().insert(name);
1297 let mut new_set = HashSet::new();
1298 new_set.insert(name);
1299 self.glob_map.insert(import_id, new_set);
1302 fn get_trait_name(&self, did: DefId) -> Name {
1303 if let Some(node_id) = self.ast_map.as_local_node_id(did) {
1304 self.ast_map.expect_item(node_id).name
1306 self.session.cstore.item_name(did)
1310 /// Check that an external crate doesn't collide with items or other external crates.
1311 fn check_for_conflicts_for_external_crate(&self, module: &Module, name: Name, span: Span) {
1312 if module.external_module_children.borrow().contains_key(&name) {
1313 span_err!(self.session,
1316 "an external crate named `{}` has already been imported into this module",
1319 match module.children.borrow().get(&name) {
1320 Some(name_bindings) if name_bindings.type_ns.defined() => {
1322 name_bindings.type_ns.span().unwrap_or(codemap::DUMMY_SP),
1323 ResolutionError::NameConflictsWithExternCrate(name));
1329 /// Checks that the names of items don't collide with external crates.
1330 fn check_for_conflicts_between_external_crates_and_items(&self,
1334 if module.external_module_children.borrow().contains_key(&name) {
1335 resolve_error(self, span, ResolutionError::NameConflictsWithExternCrate(name));
1339 /// Resolves the given module path from the given root `module_`.
1340 fn resolve_module_path_from_root(&mut self,
1341 module_: Rc<Module>,
1342 module_path: &[Name],
1345 name_search_type: NameSearchType,
1347 -> ResolveResult<(Rc<Module>, LastPrivate)> {
1348 fn search_parent_externals(needle: Name, module: &Rc<Module>) -> Option<Rc<Module>> {
1349 match module.external_module_children.borrow().get(&needle) {
1350 Some(_) => Some(module.clone()),
1351 None => match module.parent_link {
1352 ModuleParentLink(ref parent, _) => {
1353 search_parent_externals(needle, &parent.upgrade().unwrap())
1360 let mut search_module = module_;
1361 let mut index = index;
1362 let module_path_len = module_path.len();
1363 let mut closest_private = lp;
1365 // Resolve the module part of the path. This does not involve looking
1366 // upward though scope chains; we simply resolve names directly in
1367 // modules as we go.
1368 while index < module_path_len {
1369 let name = module_path[index];
1370 match self.resolve_name_in_module(search_module.clone(),
1376 let segment_name = name.as_str();
1377 let module_name = module_to_string(&*search_module);
1378 let mut span = span;
1379 let msg = if "???" == &module_name[..] {
1380 span.hi = span.lo + Pos::from_usize(segment_name.len());
1382 match search_parent_externals(name, &self.current_module) {
1384 let path_str = names_to_string(module_path);
1385 let target_mod_str = module_to_string(&*module);
1386 let current_mod_str = module_to_string(&*self.current_module);
1388 let prefix = if target_mod_str == current_mod_str {
1389 "self::".to_string()
1391 format!("{}::", target_mod_str)
1394 format!("Did you mean `{}{}`?", prefix, path_str)
1396 None => format!("Maybe a missing `extern crate {}`?", segment_name),
1399 format!("Could not find `{}` in `{}`", segment_name, module_name)
1402 return Failed(Some((span, msg)));
1404 Failed(err) => return Failed(err),
1406 debug!("(resolving module path for import) module resolution is \
1409 return Indeterminate;
1411 Success((target, used_proxy)) => {
1412 // Check to see whether there are type bindings, and, if
1413 // so, whether there is a module within.
1414 if let Some(module_def) = target.binding.module() {
1415 // track extern crates for unused_extern_crate lint
1416 if let Some(did) = module_def.def_id() {
1417 self.used_crates.insert(did.krate);
1420 search_module = module_def;
1422 // Keep track of the closest private module used
1423 // when resolving this import chain.
1424 if !used_proxy && !search_module.is_public {
1425 if let Some(did) = search_module.def_id() {
1426 closest_private = LastMod(DependsOn(did));
1430 let msg = format!("Not a module `{}`", name);
1431 return Failed(Some((span, msg)));
1439 return Success((search_module, closest_private));
1442 /// Attempts to resolve the module part of an import directive or path
1443 /// rooted at the given module.
1445 /// On success, returns the resolved module, and the closest *private*
1446 /// module found to the destination when resolving this path.
1447 fn resolve_module_path(&mut self,
1448 module_: Rc<Module>,
1449 module_path: &[Name],
1450 use_lexical_scope: UseLexicalScopeFlag,
1452 name_search_type: NameSearchType)
1453 -> ResolveResult<(Rc<Module>, LastPrivate)> {
1454 let module_path_len = module_path.len();
1455 assert!(module_path_len > 0);
1457 debug!("(resolving module path for import) processing `{}` rooted at `{}`",
1458 names_to_string(module_path),
1459 module_to_string(&*module_));
1461 // Resolve the module prefix, if any.
1462 let module_prefix_result = self.resolve_module_prefix(module_.clone(), module_path);
1467 match module_prefix_result {
1469 let mpath = names_to_string(module_path);
1470 let mpath = &mpath[..];
1471 match mpath.rfind(':') {
1473 let msg = format!("Could not find `{}` in `{}`",
1474 // idx +- 1 to account for the
1475 // colons on either side
1478 return Failed(Some((span, msg)));
1481 return Failed(None);
1485 Failed(err) => return Failed(err),
1487 debug!("(resolving module path for import) indeterminate; bailing");
1488 return Indeterminate;
1490 Success(NoPrefixFound) => {
1491 // There was no prefix, so we're considering the first element
1492 // of the path. How we handle this depends on whether we were
1493 // instructed to use lexical scope or not.
1494 match use_lexical_scope {
1495 DontUseLexicalScope => {
1496 // This is a crate-relative path. We will start the
1497 // resolution process at index zero.
1498 search_module = self.graph_root.clone();
1500 last_private = LastMod(AllPublic);
1502 UseLexicalScope => {
1503 // This is not a crate-relative path. We resolve the
1504 // first component of the path in the current lexical
1505 // scope and then proceed to resolve below that.
1506 match self.resolve_module_in_lexical_scope(module_, module_path[0]) {
1507 Failed(err) => return Failed(err),
1509 debug!("(resolving module path for import) indeterminate; bailing");
1510 return Indeterminate;
1512 Success(containing_module) => {
1513 search_module = containing_module;
1515 last_private = LastMod(AllPublic);
1521 Success(PrefixFound(ref containing_module, index)) => {
1522 search_module = containing_module.clone();
1523 start_index = index;
1524 last_private = LastMod(DependsOn(containing_module.def_id()
1529 self.resolve_module_path_from_root(search_module,
1537 /// Invariant: This must only be called during main resolution, not during
1538 /// import resolution.
1539 fn resolve_item_in_lexical_scope(&mut self,
1540 module_: Rc<Module>,
1542 namespace: Namespace,
1544 -> ResolveResult<(Target, bool)> {
1545 debug!("(resolving item in lexical scope) resolving `{}` in namespace {:?} in `{}`",
1548 module_to_string(&*module_));
1550 // The current module node is handled specially. First, check for
1551 // its immediate children.
1552 build_reduced_graph::populate_module_if_necessary(self, &module_);
1554 match module_.children.borrow().get(&name) {
1555 Some(name_bindings) if name_bindings[namespace].defined() => {
1556 debug!("top name bindings succeeded");
1557 return Success((Target::new(module_.clone(),
1558 name_bindings[namespace].clone(),
1563 // Not found; continue.
1567 // Now check for its import directives. We don't have to have resolved
1568 // all its imports in the usual way; this is because chains of
1569 // adjacent import statements are processed as though they mutated the
1571 if let Some(import_resolution) = module_.import_resolutions.borrow().get(&name) {
1572 match import_resolution[namespace].target.clone() {
1574 // Not found; continue.
1575 debug!("(resolving item in lexical scope) found import resolution, but not \
1580 debug!("(resolving item in lexical scope) using import resolution");
1581 // track used imports and extern crates as well
1582 let id = import_resolution[namespace].id;
1584 self.used_imports.insert((id, namespace));
1585 self.record_import_use(id, name);
1586 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
1587 self.used_crates.insert(kid);
1590 return Success((target, false));
1595 // Search for external modules.
1596 if namespace == TypeNS {
1597 // FIXME (21114): In principle unclear `child` *has* to be lifted.
1598 let child = module_.external_module_children.borrow().get(&name).cloned();
1599 if let Some(module) = child {
1600 let name_binding = NameBinding::create_from_module(module);
1601 debug!("lower name bindings succeeded");
1602 return Success((Target::new(module_, name_binding, Shadowable::Never),
1607 // Finally, proceed up the scope chain looking for parent modules.
1608 let mut search_module = module_;
1610 // Go to the next parent.
1611 match search_module.parent_link.clone() {
1613 // No more parents. This module was unresolved.
1614 debug!("(resolving item in lexical scope) unresolved module");
1615 return Failed(None);
1617 ModuleParentLink(parent_module_node, _) => {
1618 if search_module.is_normal() {
1619 // We stop the search here.
1620 debug!("(resolving item in lexical scope) unresolved module: not \
1621 searching through module parents");
1622 return Failed(None);
1624 search_module = parent_module_node.upgrade().unwrap();
1627 BlockParentLink(ref parent_module_node, _) => {
1628 search_module = parent_module_node.upgrade().unwrap();
1632 // Resolve the name in the parent module.
1633 match self.resolve_name_in_module(search_module.clone(),
1638 Failed(Some((span, msg))) => {
1639 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
1641 Failed(None) => (), // Continue up the search chain.
1643 // We couldn't see through the higher scope because of an
1644 // unresolved import higher up. Bail.
1646 debug!("(resolving item in lexical scope) indeterminate higher scope; bailing");
1647 return Indeterminate;
1649 Success((target, used_reexport)) => {
1650 // We found the module.
1651 debug!("(resolving item in lexical scope) found name in module, done");
1652 return Success((target, used_reexport));
1658 /// Resolves a module name in the current lexical scope.
1659 fn resolve_module_in_lexical_scope(&mut self,
1660 module_: Rc<Module>,
1662 -> ResolveResult<Rc<Module>> {
1663 // If this module is an anonymous module, resolve the item in the
1664 // lexical scope. Otherwise, resolve the item from the crate root.
1665 let resolve_result = self.resolve_item_in_lexical_scope(module_, name, TypeNS, true);
1666 match resolve_result {
1667 Success((target, _)) => {
1668 if let Some(module_def) = target.binding.module() {
1669 return Success(module_def)
1671 debug!("!!! (resolving module in lexical scope) module \
1672 wasn't actually a module!");
1673 return Failed(None);
1677 debug!("(resolving module in lexical scope) indeterminate; bailing");
1678 return Indeterminate;
1681 debug!("(resolving module in lexical scope) failed to resolve");
1687 /// Returns the nearest normal module parent of the given module.
1688 fn get_nearest_normal_module_parent(&mut self, module_: Rc<Module>) -> Option<Rc<Module>> {
1689 let mut module_ = module_;
1691 match module_.parent_link.clone() {
1692 NoParentLink => return None,
1693 ModuleParentLink(new_module, _) |
1694 BlockParentLink(new_module, _) => {
1695 let new_module = new_module.upgrade().unwrap();
1696 if new_module.is_normal() {
1697 return Some(new_module);
1699 module_ = new_module;
1705 /// Returns the nearest normal module parent of the given module, or the
1706 /// module itself if it is a normal module.
1707 fn get_nearest_normal_module_parent_or_self(&mut self, module_: Rc<Module>) -> Rc<Module> {
1708 if module_.is_normal() {
1711 match self.get_nearest_normal_module_parent(module_.clone()) {
1713 Some(new_module) => new_module,
1717 /// Resolves a "module prefix". A module prefix is one or both of (a) `self::`;
1718 /// (b) some chain of `super::`.
1719 /// grammar: (SELF MOD_SEP ) ? (SUPER MOD_SEP) *
1720 fn resolve_module_prefix(&mut self,
1721 module_: Rc<Module>,
1722 module_path: &[Name])
1723 -> ResolveResult<ModulePrefixResult> {
1724 // Start at the current module if we see `self` or `super`, or at the
1725 // top of the crate otherwise.
1726 let mut i = match &*module_path[0].as_str() {
1729 _ => return Success(NoPrefixFound),
1731 let mut containing_module = self.get_nearest_normal_module_parent_or_self(module_);
1733 // Now loop through all the `super`s we find.
1734 while i < module_path.len() && "super" == module_path[i].as_str() {
1735 debug!("(resolving module prefix) resolving `super` at {}",
1736 module_to_string(&*containing_module));
1737 match self.get_nearest_normal_module_parent(containing_module) {
1738 None => return Failed(None),
1739 Some(new_module) => {
1740 containing_module = new_module;
1746 debug!("(resolving module prefix) finished resolving prefix at {}",
1747 module_to_string(&*containing_module));
1749 return Success(PrefixFound(containing_module, i));
1752 /// Attempts to resolve the supplied name in the given module for the
1753 /// given namespace. If successful, returns the target corresponding to
1756 /// The boolean returned on success is an indicator of whether this lookup
1757 /// passed through a public re-export proxy.
1758 fn resolve_name_in_module(&mut self,
1759 module_: Rc<Module>,
1761 namespace: Namespace,
1762 name_search_type: NameSearchType,
1763 allow_private_imports: bool)
1764 -> ResolveResult<(Target, bool)> {
1765 debug!("(resolving name in module) resolving `{}` in `{}`",
1767 module_to_string(&*module_));
1769 // First, check the direct children of the module.
1770 build_reduced_graph::populate_module_if_necessary(self, &module_);
1772 match module_.children.borrow().get(&name) {
1773 Some(name_bindings) if name_bindings[namespace].defined() => {
1774 debug!("(resolving name in module) found node as child");
1775 return Success((Target::new(module_.clone(),
1776 name_bindings[namespace].clone(),
1785 // Next, check the module's imports if necessary.
1787 // If this is a search of all imports, we should be done with glob
1788 // resolution at this point.
1789 if name_search_type == PathSearch {
1790 assert_eq!(module_.glob_count.get(), 0);
1793 // Check the list of resolved imports.
1794 match module_.import_resolutions.borrow().get(&name) {
1795 Some(import_resolution) if allow_private_imports ||
1796 import_resolution[namespace].is_public => {
1798 if import_resolution[namespace].is_public &&
1799 import_resolution.outstanding_references != 0 {
1800 debug!("(resolving name in module) import unresolved; bailing out");
1801 return Indeterminate;
1803 match import_resolution[namespace].target.clone() {
1805 debug!("(resolving name in module) name found, but not in namespace {:?}",
1809 debug!("(resolving name in module) resolved to import");
1810 // track used imports and extern crates as well
1811 let id = import_resolution[namespace].id;
1812 self.used_imports.insert((id, namespace));
1813 self.record_import_use(id, name);
1814 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
1815 self.used_crates.insert(kid);
1817 return Success((target, true));
1821 Some(..) | None => {} // Continue.
1824 // Finally, search through external children.
1825 if namespace == TypeNS {
1826 // FIXME (21114): In principle unclear `child` *has* to be lifted.
1827 let child = module_.external_module_children.borrow().get(&name).cloned();
1828 if let Some(module) = child {
1829 let name_binding = NameBinding::create_from_module(module);
1830 return Success((Target::new(module_, name_binding, Shadowable::Never),
1835 // We're out of luck.
1836 debug!("(resolving name in module) failed to resolve `{}`", name);
1837 return Failed(None);
1840 fn report_unresolved_imports(&mut self, module_: Rc<Module>) {
1841 let index = module_.resolved_import_count.get();
1842 let imports = module_.imports.borrow();
1843 let import_count = imports.len();
1844 if index != import_count {
1846 (*imports)[index].span,
1847 ResolutionError::UnresolvedImport(None));
1850 // Descend into children and anonymous children.
1851 build_reduced_graph::populate_module_if_necessary(self, &module_);
1853 for (_, child_node) in module_.children.borrow().iter() {
1854 match child_node.type_ns.module() {
1858 Some(child_module) => {
1859 self.report_unresolved_imports(child_module);
1864 for (_, module_) in module_.anonymous_children.borrow().iter() {
1865 self.report_unresolved_imports(module_.clone());
1871 // We maintain a list of value ribs and type ribs.
1873 // Simultaneously, we keep track of the current position in the module
1874 // graph in the `current_module` pointer. When we go to resolve a name in
1875 // the value or type namespaces, we first look through all the ribs and
1876 // then query the module graph. When we resolve a name in the module
1877 // namespace, we can skip all the ribs (since nested modules are not
1878 // allowed within blocks in Rust) and jump straight to the current module
1881 // Named implementations are handled separately. When we find a method
1882 // call, we consult the module node to find all of the implementations in
1883 // scope. This information is lazily cached in the module node. We then
1884 // generate a fake "implementation scope" containing all the
1885 // implementations thus found, for compatibility with old resolve pass.
1887 fn with_scope<F>(&mut self, name: Option<Name>, f: F)
1888 where F: FnOnce(&mut Resolver)
1890 let orig_module = self.current_module.clone();
1892 // Move down in the graph.
1898 build_reduced_graph::populate_module_if_necessary(self, &orig_module);
1900 match orig_module.children.borrow().get(&name) {
1902 debug!("!!! (with scope) didn't find `{}` in `{}`",
1904 module_to_string(&*orig_module));
1906 Some(name_bindings) => {
1907 match name_bindings.type_ns.module() {
1909 debug!("!!! (with scope) didn't find module for `{}` in `{}`",
1911 module_to_string(&*orig_module));
1914 self.current_module = module_;
1924 self.current_module = orig_module;
1927 /// Searches the current set of local scopes for labels.
1928 /// Stops after meeting a closure.
1929 fn search_label(&self, name: Name) -> Option<DefLike> {
1930 for rib in self.label_ribs.iter().rev() {
1936 // Do not resolve labels across function boundary
1940 let result = rib.bindings.get(&name).cloned();
1941 if result.is_some() {
1948 fn resolve_crate(&mut self, krate: &hir::Crate) {
1949 debug!("(resolving crate) starting");
1951 intravisit::walk_crate(self, krate);
1954 fn check_if_primitive_type_name(&self, name: Name, span: Span) {
1955 if let Some(_) = self.primitive_type_table.primitive_types.get(&name) {
1956 span_err!(self.session,
1959 "user-defined types or type parameters cannot shadow the primitive types");
1963 fn resolve_item(&mut self, item: &Item) {
1964 let name = item.name;
1966 debug!("(resolving item) resolving {}", name);
1969 ItemEnum(_, ref generics) |
1970 ItemTy(_, ref generics) |
1971 ItemStruct(_, ref generics) => {
1972 self.check_if_primitive_type_name(name, item.span);
1974 self.with_type_parameter_rib(HasTypeParameters(generics, TypeSpace, ItemRibKind),
1975 |this| intravisit::walk_item(this, item));
1977 ItemFn(_, _, _, _, ref generics, _) => {
1978 self.with_type_parameter_rib(HasTypeParameters(generics, FnSpace, ItemRibKind),
1979 |this| intravisit::walk_item(this, item));
1982 ItemDefaultImpl(_, ref trait_ref) => {
1983 self.with_optional_trait_ref(Some(trait_ref), |_, _| {});
1985 ItemImpl(_, _, ref generics, ref opt_trait_ref, ref self_type, ref impl_items) => {
1986 self.resolve_implementation(generics,
1993 ItemTrait(_, ref generics, ref bounds, ref trait_items) => {
1994 self.check_if_primitive_type_name(name, item.span);
1996 // Create a new rib for the trait-wide type parameters.
1997 self.with_type_parameter_rib(HasTypeParameters(generics,
2001 let local_def_id = this.ast_map.local_def_id(item.id);
2002 this.with_self_rib(DefSelfTy(Some(local_def_id), None), |this| {
2003 this.visit_generics(generics);
2004 walk_list!(this, visit_ty_param_bound, bounds);
2006 for trait_item in trait_items {
2007 match trait_item.node {
2008 hir::ConstTraitItem(_, ref default) => {
2009 // Only impose the restrictions of
2010 // ConstRibKind if there's an actual constant
2011 // expression in a provided default.
2012 if default.is_some() {
2013 this.with_constant_rib(|this| {
2014 intravisit::walk_trait_item(this, trait_item)
2017 intravisit::walk_trait_item(this, trait_item)
2020 hir::MethodTraitItem(ref sig, _) => {
2021 let type_parameters =
2022 HasTypeParameters(&sig.generics,
2025 this.with_type_parameter_rib(type_parameters, |this| {
2026 intravisit::walk_trait_item(this, trait_item)
2029 hir::TypeTraitItem(..) => {
2030 this.check_if_primitive_type_name(trait_item.name,
2032 this.with_type_parameter_rib(NoTypeParameters, |this| {
2033 intravisit::walk_trait_item(this, trait_item)
2042 ItemMod(_) | ItemForeignMod(_) => {
2043 self.with_scope(Some(name), |this| {
2044 intravisit::walk_item(this, item);
2048 ItemConst(..) | ItemStatic(..) => {
2049 self.with_constant_rib(|this| {
2050 intravisit::walk_item(this, item);
2054 ItemUse(ref view_path) => {
2055 // check for imports shadowing primitive types
2056 let check_rename = |this: &Self, id, name| {
2057 match this.def_map.borrow().get(&id).map(|d| d.full_def()) {
2058 Some(DefTy(..)) | Some(DefStruct(..)) | Some(DefTrait(..)) | None => {
2059 this.check_if_primitive_type_name(name, item.span);
2065 match view_path.node {
2066 hir::ViewPathSimple(name, _) => {
2067 check_rename(self, item.id, name);
2069 hir::ViewPathList(ref prefix, ref items) => {
2071 if let Some(name) = item.node.rename() {
2072 check_rename(self, item.node.id(), name);
2076 // Resolve prefix of an import with empty braces (issue #28388)
2077 if items.is_empty() && !prefix.segments.is_empty() {
2078 match self.resolve_crate_relative_path(prefix.span,
2082 self.record_def(item.id, PathResolution::new(def, lp, 0)),
2086 ResolutionError::FailedToResolve(
2087 &path_names_to_string(prefix, 0)));
2088 self.record_def(item.id, err_path_resolution());
2097 ItemExternCrate(_) => {
2098 // do nothing, these are just around to be encoded
2103 fn with_type_parameter_rib<F>(&mut self, type_parameters: TypeParameters, f: F)
2104 where F: FnOnce(&mut Resolver)
2106 match type_parameters {
2107 HasTypeParameters(generics, space, rib_kind) => {
2108 let mut function_type_rib = Rib::new(rib_kind);
2109 let mut seen_bindings = HashSet::new();
2110 for (index, type_parameter) in generics.ty_params.iter().enumerate() {
2111 let name = type_parameter.name;
2112 debug!("with_type_parameter_rib: {}", type_parameter.id);
2114 if seen_bindings.contains(&name) {
2116 type_parameter.span,
2117 ResolutionError::NameAlreadyUsedInTypeParameterList(name));
2119 seen_bindings.insert(name);
2121 // plain insert (no renaming)
2122 function_type_rib.bindings
2124 DlDef(DefTyParam(space,
2127 .local_def_id(type_parameter.id),
2130 self.type_ribs.push(function_type_rib);
2133 NoTypeParameters => {
2140 match type_parameters {
2141 HasTypeParameters(..) => {
2143 self.type_ribs.pop();
2146 NoTypeParameters => {}
2150 fn with_label_rib<F>(&mut self, f: F)
2151 where F: FnOnce(&mut Resolver)
2153 self.label_ribs.push(Rib::new(NormalRibKind));
2156 self.label_ribs.pop();
2160 fn with_constant_rib<F>(&mut self, f: F)
2161 where F: FnOnce(&mut Resolver)
2163 self.value_ribs.push(Rib::new(ConstantItemRibKind));
2164 self.type_ribs.push(Rib::new(ConstantItemRibKind));
2167 self.type_ribs.pop();
2168 self.value_ribs.pop();
2172 fn resolve_function(&mut self, rib_kind: RibKind, declaration: &FnDecl, block: &Block) {
2173 // Create a value rib for the function.
2174 self.value_ribs.push(Rib::new(rib_kind));
2176 // Create a label rib for the function.
2177 self.label_ribs.push(Rib::new(rib_kind));
2179 // Add each argument to the rib.
2180 let mut bindings_list = HashMap::new();
2181 for argument in &declaration.inputs {
2182 self.resolve_pattern(&*argument.pat, ArgumentIrrefutableMode, &mut bindings_list);
2184 self.visit_ty(&*argument.ty);
2186 debug!("(resolving function) recorded argument");
2188 intravisit::walk_fn_ret_ty(self, &declaration.output);
2190 // Resolve the function body.
2191 self.visit_block(block);
2193 debug!("(resolving function) leaving function");
2196 self.label_ribs.pop();
2197 self.value_ribs.pop();
2201 fn resolve_trait_reference(&mut self,
2205 -> Result<PathResolution, ()> {
2206 if let Some(path_res) = self.resolve_path(id, trait_path, path_depth, TypeNS, true) {
2207 if let DefTrait(_) = path_res.base_def {
2208 debug!("(resolving trait) found trait def: {:?}", path_res);
2212 resolve_struct_error(self,
2214 ResolutionError::IsNotATrait(&*path_names_to_string(trait_path,
2217 // If it's a typedef, give a note
2218 if let DefTy(..) = path_res.base_def {
2219 err.span_note(trait_path.span,
2220 "`type` aliases cannot be used for traits");
2228 ResolutionError::UndeclaredTraitName(&*path_names_to_string(trait_path,
2234 fn resolve_generics(&mut self, generics: &Generics) {
2235 for type_parameter in generics.ty_params.iter() {
2236 self.check_if_primitive_type_name(type_parameter.name, type_parameter.span);
2238 for predicate in &generics.where_clause.predicates {
2240 &hir::WherePredicate::BoundPredicate(_) |
2241 &hir::WherePredicate::RegionPredicate(_) => {}
2242 &hir::WherePredicate::EqPredicate(ref eq_pred) => {
2243 let path_res = self.resolve_path(eq_pred.id, &eq_pred.path, 0, TypeNS, true);
2244 if let Some(PathResolution { base_def: DefTyParam(..), .. }) = path_res {
2245 self.record_def(eq_pred.id, path_res.unwrap());
2249 ResolutionError::UndeclaredAssociatedType);
2250 self.record_def(eq_pred.id, err_path_resolution());
2255 intravisit::walk_generics(self, generics);
2258 fn with_current_self_type<T, F>(&mut self, self_type: &Ty, f: F) -> T
2259 where F: FnOnce(&mut Resolver) -> T
2261 // Handle nested impls (inside fn bodies)
2262 let previous_value = replace(&mut self.current_self_type, Some(self_type.clone()));
2263 let result = f(self);
2264 self.current_self_type = previous_value;
2268 fn with_optional_trait_ref<T, F>(&mut self, opt_trait_ref: Option<&TraitRef>, f: F) -> T
2269 where F: FnOnce(&mut Resolver, Option<DefId>) -> T
2271 let mut new_val = None;
2272 let mut new_id = None;
2273 if let Some(trait_ref) = opt_trait_ref {
2274 if let Ok(path_res) = self.resolve_trait_reference(trait_ref.ref_id,
2277 assert!(path_res.depth == 0);
2278 self.record_def(trait_ref.ref_id, path_res);
2279 new_val = Some((path_res.base_def.def_id(), trait_ref.clone()));
2280 new_id = Some(path_res.base_def.def_id());
2282 self.record_def(trait_ref.ref_id, err_path_resolution());
2284 intravisit::walk_trait_ref(self, trait_ref);
2286 let original_trait_ref = replace(&mut self.current_trait_ref, new_val);
2287 let result = f(self, new_id);
2288 self.current_trait_ref = original_trait_ref;
2292 fn with_self_rib<F>(&mut self, self_def: Def, f: F)
2293 where F: FnOnce(&mut Resolver)
2295 let mut self_type_rib = Rib::new(NormalRibKind);
2297 // plain insert (no renaming, types are not currently hygienic....)
2298 let name = special_names::type_self;
2299 self_type_rib.bindings.insert(name, DlDef(self_def));
2300 self.type_ribs.push(self_type_rib);
2303 self.type_ribs.pop();
2307 fn resolve_implementation(&mut self,
2308 generics: &Generics,
2309 opt_trait_reference: &Option<TraitRef>,
2312 impl_items: &[ImplItem]) {
2313 // If applicable, create a rib for the type parameters.
2314 self.with_type_parameter_rib(HasTypeParameters(generics,
2318 // Resolve the type parameters.
2319 this.visit_generics(generics);
2321 // Resolve the trait reference, if necessary.
2322 this.with_optional_trait_ref(opt_trait_reference.as_ref(), |this, trait_id| {
2323 // Resolve the self type.
2324 this.visit_ty(self_type);
2326 this.with_self_rib(DefSelfTy(trait_id, Some((item_id, self_type.id))), |this| {
2327 this.with_current_self_type(self_type, |this| {
2328 for impl_item in impl_items {
2329 match impl_item.node {
2330 hir::ImplItemKind::Const(..) => {
2331 // If this is a trait impl, ensure the const
2333 this.check_trait_item(impl_item.name,
2335 |n, s| ResolutionError::ConstNotMemberOfTrait(n, s));
2336 this.with_constant_rib(|this| {
2337 intravisit::walk_impl_item(this, impl_item);
2340 hir::ImplItemKind::Method(ref sig, _) => {
2341 // If this is a trait impl, ensure the method
2343 this.check_trait_item(impl_item.name,
2345 |n, s| ResolutionError::MethodNotMemberOfTrait(n, s));
2347 // We also need a new scope for the method-
2348 // specific type parameters.
2349 let type_parameters =
2350 HasTypeParameters(&sig.generics,
2353 this.with_type_parameter_rib(type_parameters, |this| {
2354 intravisit::walk_impl_item(this, impl_item);
2357 hir::ImplItemKind::Type(ref ty) => {
2358 // If this is a trait impl, ensure the type
2360 this.check_trait_item(impl_item.name,
2362 |n, s| ResolutionError::TypeNotMemberOfTrait(n, s));
2374 fn check_trait_item<F>(&self, name: Name, span: Span, err: F)
2375 where F: FnOnce(Name, &str) -> ResolutionError
2377 // If there is a TraitRef in scope for an impl, then the method must be in the
2379 if let Some((did, ref trait_ref)) = self.current_trait_ref {
2380 if !self.trait_item_map.contains_key(&(name, did)) {
2381 let path_str = path_names_to_string(&trait_ref.path, 0);
2382 resolve_error(self, span, err(name, &*path_str));
2387 fn resolve_local(&mut self, local: &Local) {
2388 // Resolve the type.
2389 walk_list!(self, visit_ty, &local.ty);
2391 // Resolve the initializer.
2392 walk_list!(self, visit_expr, &local.init);
2394 // Resolve the pattern.
2395 self.resolve_pattern(&*local.pat, LocalIrrefutableMode, &mut HashMap::new());
2398 // build a map from pattern identifiers to binding-info's.
2399 // this is done hygienically. This could arise for a macro
2400 // that expands into an or-pattern where one 'x' was from the
2401 // user and one 'x' came from the macro.
2402 fn binding_mode_map(&mut self, pat: &Pat) -> BindingMap {
2403 let mut result = HashMap::new();
2404 pat_bindings(&self.def_map, pat, |binding_mode, _id, sp, path1| {
2405 let name = path1.node;
2409 binding_mode: binding_mode,
2415 // check that all of the arms in an or-pattern have exactly the
2416 // same set of bindings, with the same binding modes for each.
2417 fn check_consistent_bindings(&mut self, arm: &Arm) {
2418 if arm.pats.is_empty() {
2421 let map_0 = self.binding_mode_map(&*arm.pats[0]);
2422 for (i, p) in arm.pats.iter().enumerate() {
2423 let map_i = self.binding_mode_map(&**p);
2425 for (&key, &binding_0) in &map_0 {
2426 match map_i.get(&key) {
2430 ResolutionError::VariableNotBoundInPattern(key, i + 1));
2432 Some(binding_i) => {
2433 if binding_0.binding_mode != binding_i.binding_mode {
2436 ResolutionError::VariableBoundWithDifferentMode(key,
2443 for (&key, &binding) in &map_i {
2444 if !map_0.contains_key(&key) {
2447 ResolutionError::VariableNotBoundInParentPattern(key, i + 1));
2453 fn resolve_arm(&mut self, arm: &Arm) {
2454 self.value_ribs.push(Rib::new(NormalRibKind));
2456 let mut bindings_list = HashMap::new();
2457 for pattern in &arm.pats {
2458 self.resolve_pattern(&**pattern, RefutableMode, &mut bindings_list);
2461 // This has to happen *after* we determine which
2462 // pat_idents are variants
2463 self.check_consistent_bindings(arm);
2465 walk_list!(self, visit_expr, &arm.guard);
2466 self.visit_expr(&*arm.body);
2469 self.value_ribs.pop();
2473 fn resolve_block(&mut self, block: &Block) {
2474 debug!("(resolving block) entering block");
2475 self.value_ribs.push(Rib::new(NormalRibKind));
2477 // Move down in the graph, if there's an anonymous module rooted here.
2478 let orig_module = self.current_module.clone();
2479 match orig_module.anonymous_children.borrow().get(&block.id) {
2483 Some(anonymous_module) => {
2484 debug!("(resolving block) found anonymous module, moving down");
2485 self.current_module = anonymous_module.clone();
2489 // Check for imports appearing after non-item statements.
2490 let mut found_non_item = false;
2491 for statement in &block.stmts {
2492 if let hir::StmtDecl(ref declaration, _) = statement.node {
2493 if let hir::DeclItem(i) = declaration.node {
2494 let i = self.ast_map.expect_item(i.id);
2496 ItemExternCrate(_) | ItemUse(_) if found_non_item => {
2497 span_err!(self.session,
2500 "imports are not allowed after non-item statements");
2505 found_non_item = true
2508 found_non_item = true;
2512 // Descend into the block.
2513 intravisit::walk_block(self, block);
2517 self.current_module = orig_module;
2518 self.value_ribs.pop();
2520 debug!("(resolving block) leaving block");
2523 fn resolve_type(&mut self, ty: &Ty) {
2525 TyPath(ref maybe_qself, ref path) => {
2526 let resolution = match self.resolve_possibly_assoc_item(ty.id,
2527 maybe_qself.as_ref(),
2531 // `<T>::a::b::c` is resolved by typeck alone.
2532 TypecheckRequired => {
2533 // Resolve embedded types.
2534 intravisit::walk_ty(self, ty);
2537 ResolveAttempt(resolution) => resolution,
2540 // This is a path in the type namespace. Walk through scopes
2544 // Write the result into the def map.
2545 debug!("(resolving type) writing resolution for `{}` (id {}) = {:?}",
2546 path_names_to_string(path, 0),
2549 self.record_def(ty.id, def);
2552 self.record_def(ty.id, err_path_resolution());
2554 // Keep reporting some errors even if they're ignored above.
2555 self.resolve_path(ty.id, path, 0, TypeNS, true);
2557 let kind = if maybe_qself.is_some() {
2563 let self_type_name = special_idents::type_self.name;
2564 let is_invalid_self_type_name = path.segments.len() > 0 &&
2565 maybe_qself.is_none() &&
2566 path.segments[0].identifier.name ==
2568 if is_invalid_self_type_name {
2571 ResolutionError::SelfUsedOutsideImplOrTrait);
2575 ResolutionError::UseOfUndeclared(
2577 &*path_names_to_string(path,
2586 // Resolve embedded types.
2587 intravisit::walk_ty(self, ty);
2590 fn resolve_pattern(&mut self,
2592 mode: PatternBindingMode,
2593 // Maps idents to the node ID for the (outermost)
2594 // pattern that binds them
2595 bindings_list: &mut HashMap<Name, NodeId>) {
2596 let pat_id = pattern.id;
2597 walk_pat(pattern, |pattern| {
2598 match pattern.node {
2599 PatIdent(binding_mode, ref path1, ref at_rhs) => {
2600 // The meaning of PatIdent with no type parameters
2601 // depends on whether an enum variant or unit-like struct
2602 // with that name is in scope. The probing lookup has to
2603 // be careful not to emit spurious errors. Only matching
2604 // patterns (match) can match nullary variants or
2605 // unit-like structs. For binding patterns (let
2606 // and the LHS of @-patterns), matching such a value is
2607 // simply disallowed (since it's rarely what you want).
2608 let const_ok = mode == RefutableMode && at_rhs.is_none();
2610 let ident = path1.node;
2611 let renamed = ident.name;
2613 match self.resolve_bare_identifier_pattern(ident.unhygienic_name,
2615 FoundStructOrEnumVariant(def, lp) if const_ok => {
2616 debug!("(resolving pattern) resolving `{}` to struct or enum variant",
2619 self.enforce_default_binding_mode(pattern,
2622 self.record_def(pattern.id,
2629 FoundStructOrEnumVariant(..) => {
2633 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(
2636 self.record_def(pattern.id, err_path_resolution());
2638 FoundConst(def, lp, _) if const_ok => {
2639 debug!("(resolving pattern) resolving `{}` to constant", renamed);
2641 self.enforce_default_binding_mode(pattern, binding_mode, "a constant");
2642 self.record_def(pattern.id,
2649 FoundConst(def, _, name) => {
2653 ResolutionError::OnlyIrrefutablePatternsAllowedHere(def.def_id(),
2656 self.record_def(pattern.id, err_path_resolution());
2658 BareIdentifierPatternUnresolved => {
2659 debug!("(resolving pattern) binding `{}`", renamed);
2661 let def_id = self.ast_map.local_def_id(pattern.id);
2662 let def = DefLocal(def_id, pattern.id);
2664 // Record the definition so that later passes
2665 // will be able to distinguish variants from
2666 // locals in patterns.
2668 self.record_def(pattern.id,
2671 last_private: LastMod(AllPublic),
2675 // Add the binding to the local ribs, if it
2676 // doesn't already exist in the bindings list. (We
2677 // must not add it if it's in the bindings list
2678 // because that breaks the assumptions later
2679 // passes make about or-patterns.)
2680 if !bindings_list.contains_key(&renamed) {
2681 let this = &mut *self;
2682 let last_rib = this.value_ribs.last_mut().unwrap();
2683 last_rib.bindings.insert(renamed, DlDef(def));
2684 bindings_list.insert(renamed, pat_id);
2685 } else if mode == ArgumentIrrefutableMode &&
2686 bindings_list.contains_key(&renamed) {
2687 // Forbid duplicate bindings in the same
2692 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(
2693 &ident.name.as_str())
2695 } else if bindings_list.get(&renamed) == Some(&pat_id) {
2696 // Then this is a duplicate variable in the
2697 // same disjunction, which is an error.
2701 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(
2702 &ident.name.as_str())
2705 // Else, not bound in the same pattern: do
2711 PatEnum(ref path, _) => {
2712 // This must be an enum variant, struct or const.
2713 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2718 // The below shouldn't happen because all
2719 // qualified paths should be in PatQPath.
2720 TypecheckRequired =>
2721 self.session.span_bug(path.span,
2722 "resolve_possibly_assoc_item claimed
2724 that a path in PatEnum requires typecheck
2726 to resolve, but qualified paths should be
2729 ResolveAttempt(resolution) => resolution,
2731 if let Some(path_res) = resolution {
2732 match path_res.base_def {
2733 DefVariant(..) | DefStruct(..) | DefConst(..) => {
2734 self.record_def(pattern.id, path_res);
2737 resolve_error(&self,
2739 ResolutionError::StaticVariableReference);
2740 self.record_def(pattern.id, err_path_resolution());
2743 // If anything ends up here entirely resolved,
2744 // it's an error. If anything ends up here
2745 // partially resolved, that's OK, because it may
2746 // be a `T::CONST` that typeck will resolve.
2747 if path_res.depth == 0 {
2751 ResolutionError::NotAnEnumVariantStructOrConst(
2759 self.record_def(pattern.id, err_path_resolution());
2761 let const_name = path.segments
2766 let traits = self.get_traits_containing_item(const_name);
2767 self.trait_map.insert(pattern.id, traits);
2768 self.record_def(pattern.id, path_res);
2776 ResolutionError::UnresolvedEnumVariantStructOrConst(
2777 &path.segments.last().unwrap().identifier.name.as_str())
2779 self.record_def(pattern.id, err_path_resolution());
2781 intravisit::walk_path(self, path);
2784 PatQPath(ref qself, ref path) => {
2785 // Associated constants only.
2786 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2791 TypecheckRequired => {
2792 // All `<T>::CONST` should end up here, and will
2793 // require use of the trait map to resolve
2794 // during typechecking.
2795 let const_name = path.segments
2800 let traits = self.get_traits_containing_item(const_name);
2801 self.trait_map.insert(pattern.id, traits);
2802 intravisit::walk_pat(self, pattern);
2805 ResolveAttempt(resolution) => resolution,
2807 if let Some(path_res) = resolution {
2808 match path_res.base_def {
2809 // All `<T as Trait>::CONST` should end up here, and
2810 // have the trait already selected.
2811 DefAssociatedConst(..) => {
2812 self.record_def(pattern.id, path_res);
2818 ResolutionError::NotAnAssociatedConst(
2819 &path.segments.last().unwrap().identifier.name.as_str()
2822 self.record_def(pattern.id, err_path_resolution());
2828 ResolutionError::UnresolvedAssociatedConst(&path.segments
2834 self.record_def(pattern.id, err_path_resolution());
2836 intravisit::walk_pat(self, pattern);
2839 PatStruct(ref path, _, _) => {
2840 match self.resolve_path(pat_id, path, 0, TypeNS, false) {
2841 Some(definition) => {
2842 self.record_def(pattern.id, definition);
2845 debug!("(resolving pattern) didn't find struct def: {:?}", result);
2849 ResolutionError::DoesNotNameAStruct(
2850 &*path_names_to_string(path, 0))
2852 self.record_def(pattern.id, err_path_resolution());
2855 intravisit::walk_path(self, path);
2858 PatLit(_) | PatRange(..) => {
2859 intravisit::walk_pat(self, pattern);
2870 fn resolve_bare_identifier_pattern(&mut self,
2873 -> BareIdentifierPatternResolution {
2874 let module = self.current_module.clone();
2875 match self.resolve_item_in_lexical_scope(module, name, ValueNS, true) {
2876 Success((target, _)) => {
2877 debug!("(resolve bare identifier pattern) succeeded in finding {} at {:?}",
2879 target.binding.borrow());
2880 match target.binding.def() {
2882 panic!("resolved name in the value namespace to a set of name bindings \
2885 // For the two success cases, this lookup can be
2886 // considered as not having a private component because
2887 // the lookup happened only within the current module.
2888 Some(def @ DefVariant(..)) | Some(def @ DefStruct(..)) => {
2889 return FoundStructOrEnumVariant(def, LastMod(AllPublic));
2891 Some(def @ DefConst(..)) | Some(def @ DefAssociatedConst(..)) => {
2892 return FoundConst(def, LastMod(AllPublic), name);
2894 Some(DefStatic(..)) => {
2895 resolve_error(self, span, ResolutionError::StaticVariableReference);
2896 return BareIdentifierPatternUnresolved;
2898 _ => return BareIdentifierPatternUnresolved
2903 panic!("unexpected indeterminate result");
2907 Some((span, msg)) => {
2908 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
2913 debug!("(resolve bare identifier pattern) failed to find {}", name);
2914 return BareIdentifierPatternUnresolved;
2919 /// Handles paths that may refer to associated items
2920 fn resolve_possibly_assoc_item(&mut self,
2922 maybe_qself: Option<&hir::QSelf>,
2924 namespace: Namespace,
2926 -> AssocItemResolveResult {
2927 let max_assoc_types;
2931 if qself.position == 0 {
2932 return TypecheckRequired;
2934 max_assoc_types = path.segments.len() - qself.position;
2935 // Make sure the trait is valid.
2936 let _ = self.resolve_trait_reference(id, path, max_assoc_types);
2939 max_assoc_types = path.segments.len();
2943 let mut resolution = self.with_no_errors(|this| {
2944 this.resolve_path(id, path, 0, namespace, check_ribs)
2946 for depth in 1..max_assoc_types {
2947 if resolution.is_some() {
2950 self.with_no_errors(|this| {
2951 resolution = this.resolve_path(id, path, depth, TypeNS, true);
2954 if let Some(DefMod(_)) = resolution.map(|r| r.base_def) {
2955 // A module is not a valid type or value.
2958 ResolveAttempt(resolution)
2961 /// If `check_ribs` is true, checks the local definitions first; i.e.
2962 /// doesn't skip straight to the containing module.
2963 /// Skips `path_depth` trailing segments, which is also reflected in the
2964 /// returned value. See `middle::def::PathResolution` for more info.
2965 pub fn resolve_path(&mut self,
2969 namespace: Namespace,
2971 -> Option<PathResolution> {
2972 let span = path.span;
2973 let segments = &path.segments[..path.segments.len() - path_depth];
2975 let mk_res = |(def, lp)| PathResolution::new(def, lp, path_depth);
2978 let def = self.resolve_crate_relative_path(span, segments, namespace);
2979 return def.map(mk_res);
2982 // Try to find a path to an item in a module.
2983 let last_ident = segments.last().unwrap().identifier;
2984 if segments.len() <= 1 {
2985 let unqualified_def = self.resolve_identifier(last_ident, namespace, check_ribs, true);
2986 return unqualified_def.and_then(|def| self.adjust_local_def(def, span))
2988 PathResolution::new(def, LastMod(AllPublic), path_depth)
2992 let unqualified_def = self.resolve_identifier(last_ident, namespace, check_ribs, false);
2993 let def = self.resolve_module_relative_path(span, segments, namespace);
2994 match (def, unqualified_def) {
2995 (Some((ref d, _)), Some(ref ud)) if *d == ud.def => {
2997 .add_lint(lint::builtin::UNUSED_QUALIFICATIONS,
3000 "unnecessary qualification".to_string());
3008 // Resolve a single identifier
3009 fn resolve_identifier(&mut self,
3010 identifier: hir::Ident,
3011 namespace: Namespace,
3014 -> Option<LocalDef> {
3015 // First, check to see whether the name is a primitive type.
3016 if namespace == TypeNS {
3017 if let Some(&prim_ty) = self.primitive_type_table
3019 .get(&identifier.unhygienic_name) {
3020 return Some(LocalDef::from_def(DefPrimTy(prim_ty)));
3025 if let Some(def) = self.resolve_identifier_in_local_ribs(identifier, namespace) {
3030 let name = identifier.unhygienic_name;
3031 self.resolve_item_by_name_in_lexical_scope(name, namespace, record_used)
3032 .map(LocalDef::from_def)
3035 // Resolve a local definition, potentially adjusting for closures.
3036 fn adjust_local_def(&mut self, local_def: LocalDef, span: Span) -> Option<Def> {
3037 let ribs = match local_def.ribs {
3038 Some((TypeNS, i)) => &self.type_ribs[i + 1..],
3039 Some((ValueNS, i)) => &self.value_ribs[i + 1..],
3042 let mut def = local_def.def;
3045 self.session.span_bug(span, &format!("unexpected {:?} in bindings", def))
3047 DefLocal(_, node_id) => {
3051 // Nothing to do. Continue.
3053 ClosureRibKind(function_id) => {
3055 let node_def_id = self.ast_map.local_def_id(node_id);
3057 let seen = self.freevars_seen
3059 .or_insert_with(|| NodeMap());
3060 if let Some(&index) = seen.get(&node_id) {
3061 def = DefUpvar(node_def_id, node_id, index, function_id);
3064 let vec = self.freevars
3066 .or_insert_with(|| vec![]);
3067 let depth = vec.len();
3073 def = DefUpvar(node_def_id, node_id, depth, function_id);
3074 seen.insert(node_id, depth);
3076 ItemRibKind | MethodRibKind => {
3077 // This was an attempt to access an upvar inside a
3078 // named function item. This is not allowed, so we
3082 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem);
3085 ConstantItemRibKind => {
3086 // Still doesn't deal with upvars
3089 ResolutionError::AttemptToUseNonConstantValueInConstant);
3095 DefTyParam(..) | DefSelfTy(..) => {
3098 NormalRibKind | MethodRibKind | ClosureRibKind(..) => {
3099 // Nothing to do. Continue.
3102 // This was an attempt to use a type parameter outside
3107 ResolutionError::TypeParametersFromOuterFunction);
3110 ConstantItemRibKind => {
3112 resolve_error(self, span, ResolutionError::OuterTypeParameterContext);
3123 // resolve a "module-relative" path, e.g. a::b::c
3124 fn resolve_module_relative_path(&mut self,
3126 segments: &[hir::PathSegment],
3127 namespace: Namespace)
3128 -> Option<(Def, LastPrivate)> {
3129 let module_path = segments.split_last()
3133 .map(|ps| ps.identifier.name)
3134 .collect::<Vec<_>>();
3136 let containing_module;
3138 let current_module = self.current_module.clone();
3139 match self.resolve_module_path(current_module,
3145 let (span, msg) = match err {
3146 Some((span, msg)) => (span, msg),
3148 let msg = format!("Use of undeclared type or module `{}`",
3149 names_to_string(&module_path));
3154 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
3157 Indeterminate => panic!("indeterminate unexpected"),
3158 Success((resulting_module, resulting_last_private)) => {
3159 containing_module = resulting_module;
3160 last_private = resulting_last_private;
3164 let name = segments.last().unwrap().identifier.name;
3165 let def = match self.resolve_name_in_module(containing_module.clone(),
3168 NameSearchType::PathSearch,
3170 Success((Target { binding, .. }, _)) => {
3171 let (def, lp) = binding.def_and_lp();
3172 (def, last_private.or(lp))
3176 if let Some(DefId{krate: kid, ..}) = containing_module.def_id() {
3177 self.used_crates.insert(kid);
3182 /// Invariant: This must be called only during main resolution, not during
3183 /// import resolution.
3184 fn resolve_crate_relative_path(&mut self,
3186 segments: &[hir::PathSegment],
3187 namespace: Namespace)
3188 -> Option<(Def, LastPrivate)> {
3189 let module_path = segments.split_last()
3193 .map(|ps| ps.identifier.name)
3194 .collect::<Vec<_>>();
3196 let root_module = self.graph_root.clone();
3198 let containing_module;
3200 match self.resolve_module_path_from_root(root_module,
3205 LastMod(AllPublic)) {
3207 let (span, msg) = match err {
3208 Some((span, msg)) => (span, msg),
3210 let msg = format!("Use of undeclared module `::{}`",
3211 names_to_string(&module_path[..]));
3216 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg));
3221 panic!("indeterminate unexpected");
3224 Success((resulting_module, resulting_last_private)) => {
3225 containing_module = resulting_module;
3226 last_private = resulting_last_private;
3230 let name = segments.last().unwrap().identifier.name;
3231 match self.resolve_name_in_module(containing_module,
3234 NameSearchType::PathSearch,
3236 Success((Target { binding, .. }, _)) => {
3237 let (def, lp) = binding.def_and_lp();
3238 Some((def, last_private.or(lp)))
3244 fn resolve_identifier_in_local_ribs(&mut self,
3246 namespace: Namespace)
3247 -> Option<LocalDef> {
3248 // Check the local set of ribs.
3249 let (name, ribs) = match namespace {
3250 ValueNS => (ident.name, &self.value_ribs),
3251 TypeNS => (ident.unhygienic_name, &self.type_ribs),
3254 for (i, rib) in ribs.iter().enumerate().rev() {
3255 if let Some(def_like) = rib.bindings.get(&name).cloned() {
3258 debug!("(resolving path in local ribs) resolved `{}` to {:?} at {}",
3262 return Some(LocalDef {
3263 ribs: Some((namespace, i)),
3268 debug!("(resolving path in local ribs) resolved `{}` to pseudo-def {:?}",
3280 fn resolve_item_by_name_in_lexical_scope(&mut self,
3282 namespace: Namespace,
3286 let module = self.current_module.clone();
3287 match self.resolve_item_in_lexical_scope(module, name, namespace, record_used) {
3288 Success((target, _)) => {
3289 match target.binding.def() {
3291 // This can happen if we were looking for a type and
3292 // found a module instead. Modules don't have defs.
3293 debug!("(resolving item path by identifier in lexical scope) failed to \
3294 resolve {} after success...",
3299 debug!("(resolving item path in lexical scope) resolved `{}` to item",
3301 // This lookup is "all public" because it only searched
3302 // for one identifier in the current module (couldn't
3303 // have passed through reexports or anything like that.
3309 panic!("unexpected indeterminate result");
3312 debug!("(resolving item path by identifier in lexical scope) failed to resolve {}",
3315 if let Some((span, msg)) = err {
3316 resolve_error(self, span, ResolutionError::FailedToResolve(&*msg))
3324 fn with_no_errors<T, F>(&mut self, f: F) -> T
3325 where F: FnOnce(&mut Resolver) -> T
3327 self.emit_errors = false;
3329 self.emit_errors = true;
3333 fn find_fallback_in_self_type(&mut self, name: Name) -> FallbackSuggestion {
3334 fn extract_path_and_node_id(t: &Ty,
3335 allow: FallbackChecks)
3336 -> Option<(Path, NodeId, FallbackChecks)> {
3338 TyPath(None, ref path) => Some((path.clone(), t.id, allow)),
3339 TyPtr(ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, OnlyTraitAndStatics),
3340 TyRptr(_, ref mut_ty) => extract_path_and_node_id(&*mut_ty.ty, allow),
3341 // This doesn't handle the remaining `Ty` variants as they are not
3342 // that commonly the self_type, it might be interesting to provide
3343 // support for those in future.
3348 fn get_module(this: &mut Resolver,
3350 name_path: &[ast::Name])
3351 -> Option<Rc<Module>> {
3352 let root = this.current_module.clone();
3353 let last_name = name_path.last().unwrap();
3355 if name_path.len() == 1 {
3356 match this.primitive_type_table.primitive_types.get(last_name) {
3359 match this.current_module.children.borrow().get(last_name) {
3360 Some(child) => child.type_ns.module(),
3366 match this.resolve_module_path(root,
3371 Success((module, _)) => Some(module),
3377 fn is_static_method(this: &Resolver, did: DefId) -> bool {
3378 if let Some(node_id) = this.ast_map.as_local_node_id(did) {
3379 let sig = match this.ast_map.get(node_id) {
3380 hir_map::NodeTraitItem(trait_item) => match trait_item.node {
3381 hir::MethodTraitItem(ref sig, _) => sig,
3384 hir_map::NodeImplItem(impl_item) => match impl_item.node {
3385 hir::ImplItemKind::Method(ref sig, _) => sig,
3390 sig.explicit_self.node == hir::SelfStatic
3392 this.session.cstore.is_static_method(did)
3396 let (path, node_id, allowed) = match self.current_self_type {
3397 Some(ref ty) => match extract_path_and_node_id(ty, Everything) {
3399 None => return NoSuggestion,
3401 None => return NoSuggestion,
3404 if allowed == Everything {
3405 // Look for a field with the same name in the current self_type.
3406 match self.def_map.borrow().get(&node_id).map(|d| d.full_def()) {
3407 Some(DefTy(did, _)) |
3408 Some(DefStruct(did)) |
3409 Some(DefVariant(_, did, _)) => match self.structs.get(&did) {
3412 if fields.iter().any(|&field_name| name == field_name) {
3417 _ => {} // Self type didn't resolve properly
3421 let name_path = path.segments.iter().map(|seg| seg.identifier.name).collect::<Vec<_>>();
3423 // Look for a method in the current self type's impl module.
3424 if let Some(module) = get_module(self, path.span, &name_path) {
3425 if let Some(binding) = module.children.borrow().get(&name) {
3426 if let Some(DefMethod(did)) = binding.value_ns.def() {
3427 if is_static_method(self, did) {
3428 return StaticMethod(path_names_to_string(&path, 0));
3430 if self.current_trait_ref.is_some() {
3432 } else if allowed == Everything {
3439 // Look for a method in the current trait.
3440 if let Some((trait_did, ref trait_ref)) = self.current_trait_ref {
3441 if let Some(&did) = self.trait_item_map.get(&(name, trait_did)) {
3442 if is_static_method(self, did) {
3443 return TraitMethod(path_names_to_string(&trait_ref.path, 0));
3453 fn find_best_match(&mut self, name: &str) -> SuggestionType {
3454 if let Some(macro_name) = self.session.available_macros
3455 .borrow().iter().find(|n| n.as_str() == name) {
3456 return SuggestionType::Macro(format!("{}!", macro_name));
3459 let names = self.value_ribs
3462 .flat_map(|rib| rib.bindings.keys());
3464 if let Some(found) = find_best_match_for_name(names, name, None) {
3465 if name != &*found {
3466 return SuggestionType::Function(found);
3468 } SuggestionType::NotFound
3471 fn resolve_expr(&mut self, expr: &Expr) {
3472 // First, record candidate traits for this expression if it could
3473 // result in the invocation of a method call.
3475 self.record_candidate_traits_for_expr_if_necessary(expr);
3477 // Next, resolve the node.
3479 ExprPath(ref maybe_qself, ref path) => {
3480 let resolution = match self.resolve_possibly_assoc_item(expr.id,
3481 maybe_qself.as_ref(),
3485 // `<T>::a::b::c` is resolved by typeck alone.
3486 TypecheckRequired => {
3487 let method_name = path.segments.last().unwrap().identifier.name;
3488 let traits = self.get_traits_containing_item(method_name);
3489 self.trait_map.insert(expr.id, traits);
3490 intravisit::walk_expr(self, expr);
3493 ResolveAttempt(resolution) => resolution,
3496 // This is a local path in the value namespace. Walk through
3497 // scopes looking for it.
3498 if let Some(path_res) = resolution {
3499 // Check if struct variant
3500 if let DefVariant(_, _, true) = path_res.base_def {
3501 let path_name = path_names_to_string(path, 0);
3503 let mut err = resolve_struct_error(self,
3505 ResolutionError::StructVariantUsedAsFunction(&*path_name));
3507 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3509 if self.emit_errors {
3510 err.fileline_help(expr.span, &msg);
3512 err.span_help(expr.span, &msg);
3515 self.record_def(expr.id, err_path_resolution());
3517 // Write the result into the def map.
3518 debug!("(resolving expr) resolved `{}`",
3519 path_names_to_string(path, 0));
3521 // Partial resolutions will need the set of traits in scope,
3522 // so they can be completed during typeck.
3523 if path_res.depth != 0 {
3524 let method_name = path.segments.last().unwrap().identifier.name;
3525 let traits = self.get_traits_containing_item(method_name);
3526 self.trait_map.insert(expr.id, traits);
3529 self.record_def(expr.id, path_res);
3532 // Be helpful if the name refers to a struct
3533 // (The pattern matching def_tys where the id is in self.structs
3534 // matches on regular structs while excluding tuple- and enum-like
3535 // structs, which wouldn't result in this error.)
3536 let path_name = path_names_to_string(path, 0);
3537 let type_res = self.with_no_errors(|this| {
3538 this.resolve_path(expr.id, path, 0, TypeNS, false)
3541 self.record_def(expr.id, err_path_resolution());
3542 match type_res.map(|r| r.base_def) {
3543 Some(DefTy(struct_id, _)) if self.structs.contains_key(&struct_id) => {
3544 let mut err = resolve_struct_error(self,
3546 ResolutionError::StructVariantUsedAsFunction(&*path_name));
3548 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3550 if self.emit_errors {
3551 err.fileline_help(expr.span, &msg);
3553 err.span_help(expr.span, &msg);
3558 // Keep reporting some errors even if they're ignored above.
3559 self.resolve_path(expr.id, path, 0, ValueNS, true);
3561 let mut method_scope = false;
3562 self.value_ribs.iter().rev().all(|rib| {
3563 method_scope = match rib.kind {
3564 MethodRibKind => true,
3565 ItemRibKind | ConstantItemRibKind => false,
3566 _ => return true, // Keep advancing
3568 false // Stop advancing
3571 if method_scope && special_names::self_.as_str() == &path_name[..] {
3574 ResolutionError::SelfNotAvailableInStaticMethod);
3576 let last_name = path.segments.last().unwrap().identifier.name;
3577 let mut msg = match self.find_fallback_in_self_type(last_name) {
3579 // limit search to 5 to reduce the number
3580 // of stupid suggestions
3581 match self.find_best_match(&path_name) {
3582 SuggestionType::Macro(s) => {
3583 format!("the macro `{}`", s)
3585 SuggestionType::Function(s) => format!("`{}`", s),
3586 SuggestionType::NotFound => "".to_string(),
3589 Field => format!("`self.{}`", path_name),
3591 TraitItem => format!("to call `self.{}`", path_name),
3592 TraitMethod(path_str) |
3593 StaticMethod(path_str) =>
3594 format!("to call `{}::{}`", path_str, path_name),
3597 let mut context = UnresolvedNameContext::Other;
3598 if !msg.is_empty() {
3599 msg = format!(". Did you mean {}?", msg);
3601 // we check if this a module and if so, we display a help
3603 let name_path = path.segments.iter()
3604 .map(|seg| seg.identifier.name)
3605 .collect::<Vec<_>>();
3606 let current_module = self.current_module.clone();
3608 match self.resolve_module_path(current_module,
3614 context = UnresolvedNameContext::PathIsMod(expr.id);
3622 ResolutionError::UnresolvedName(
3623 &*path_name, &*msg, context));
3629 intravisit::walk_expr(self, expr);
3632 ExprStruct(ref path, _, _) => {
3633 // Resolve the path to the structure it goes to. We don't
3634 // check to ensure that the path is actually a structure; that
3635 // is checked later during typeck.
3636 match self.resolve_path(expr.id, path, 0, TypeNS, false) {
3637 Some(definition) => self.record_def(expr.id, definition),
3639 debug!("(resolving expression) didn't find struct def",);
3643 ResolutionError::DoesNotNameAStruct(
3644 &*path_names_to_string(path, 0))
3646 self.record_def(expr.id, err_path_resolution());
3650 intravisit::walk_expr(self, expr);
3653 ExprLoop(_, Some(label)) | ExprWhile(_, _, Some(label)) => {
3654 self.with_label_rib(|this| {
3655 let def_like = DlDef(DefLabel(expr.id));
3658 let rib = this.label_ribs.last_mut().unwrap();
3659 rib.bindings.insert(label.name, def_like);
3662 intravisit::walk_expr(this, expr);
3666 ExprBreak(Some(label)) | ExprAgain(Some(label)) => {
3667 match self.search_label(label.node.name) {
3669 self.record_def(expr.id, err_path_resolution());
3672 ResolutionError::UndeclaredLabel(&label.node.name.as_str()))
3674 Some(DlDef(def @ DefLabel(_))) => {
3675 // Since this def is a label, it is never read.
3676 self.record_def(expr.id,
3679 last_private: LastMod(AllPublic),
3684 self.session.span_bug(expr.span, "label wasn't mapped to a label def!")
3690 intravisit::walk_expr(self, expr);
3695 fn record_candidate_traits_for_expr_if_necessary(&mut self, expr: &Expr) {
3697 ExprField(_, name) => {
3698 // FIXME(#6890): Even though you can't treat a method like a
3699 // field, we need to add any trait methods we find that match
3700 // the field name so that we can do some nice error reporting
3701 // later on in typeck.
3702 let traits = self.get_traits_containing_item(name.node);
3703 self.trait_map.insert(expr.id, traits);
3705 ExprMethodCall(name, _, _) => {
3706 debug!("(recording candidate traits for expr) recording traits for {}",
3708 let traits = self.get_traits_containing_item(name.node);
3709 self.trait_map.insert(expr.id, traits);
3717 fn get_traits_containing_item(&mut self, name: Name) -> Vec<DefId> {
3718 debug!("(getting traits containing item) looking for '{}'", name);
3720 fn add_trait_info(found_traits: &mut Vec<DefId>, trait_def_id: DefId, name: Name) {
3721 debug!("(adding trait info) found trait {:?} for method '{}'",
3724 found_traits.push(trait_def_id);
3727 let mut found_traits = Vec::new();
3728 let mut search_module = self.current_module.clone();
3730 // Look for the current trait.
3731 match self.current_trait_ref {
3732 Some((trait_def_id, _)) => {
3733 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3734 add_trait_info(&mut found_traits, trait_def_id, name);
3737 None => {} // Nothing to do.
3740 // Look for trait children.
3741 build_reduced_graph::populate_module_if_necessary(self, &search_module);
3744 for (_, child_names) in search_module.children.borrow().iter() {
3745 let def = match child_names.type_ns.def() {
3749 let trait_def_id = match def {
3750 DefTrait(trait_def_id) => trait_def_id,
3753 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3754 add_trait_info(&mut found_traits, trait_def_id, name);
3759 // Look for imports.
3760 for (_, import) in search_module.import_resolutions.borrow().iter() {
3761 let target = match import.type_ns.target {
3763 Some(ref target) => target,
3765 let did = match target.binding.def() {
3766 Some(DefTrait(trait_def_id)) => trait_def_id,
3767 Some(..) | None => continue,
3769 if self.trait_item_map.contains_key(&(name, did)) {
3770 add_trait_info(&mut found_traits, did, name);
3771 let id = import.type_ns.id;
3772 self.used_imports.insert((id, TypeNS));
3773 let trait_name = self.get_trait_name(did);
3774 self.record_import_use(id, trait_name);
3775 if let Some(DefId{krate: kid, ..}) = target.target_module.def_id() {
3776 self.used_crates.insert(kid);
3781 match search_module.parent_link.clone() {
3782 NoParentLink | ModuleParentLink(..) => break,
3783 BlockParentLink(parent_module, _) => {
3784 search_module = parent_module.upgrade().unwrap();
3792 fn record_def(&mut self, node_id: NodeId, resolution: PathResolution) {
3793 debug!("(recording def) recording {:?} for {}", resolution, node_id);
3794 assert!(match resolution.last_private {
3795 LastImport{..} => false,
3798 "Import should only be used for `use` directives");
3800 if let Some(prev_res) = self.def_map.borrow_mut().insert(node_id, resolution) {
3801 let span = self.ast_map.opt_span(node_id).unwrap_or(codemap::DUMMY_SP);
3802 self.session.span_bug(span,
3803 &format!("path resolved multiple times ({:?} before, {:?} now)",
3809 fn enforce_default_binding_mode(&mut self,
3811 pat_binding_mode: BindingMode,
3813 match pat_binding_mode {
3814 BindByValue(_) => {}
3818 ResolutionError::CannotUseRefBindingModeWith(descr));
3826 // Diagnostics are not particularly efficient, because they're rarely
3830 #[allow(dead_code)] // useful for debugging
3831 fn dump_module(&mut self, module_: Rc<Module>) {
3832 debug!("Dump of module `{}`:", module_to_string(&*module_));
3834 debug!("Children:");
3835 build_reduced_graph::populate_module_if_necessary(self, &module_);
3836 for (&name, _) in module_.children.borrow().iter() {
3837 debug!("* {}", name);
3840 debug!("Import resolutions:");
3841 let import_resolutions = module_.import_resolutions.borrow();
3842 for (&name, import_resolution) in import_resolutions.iter() {
3844 match import_resolution.value_ns.target {
3846 value_repr = "".to_string();
3849 value_repr = " value:?".to_string();
3855 match import_resolution.type_ns.target {
3857 type_repr = "".to_string();
3860 type_repr = " type:?".to_string();
3865 debug!("* {}:{}{}", name, value_repr, type_repr);
3871 fn names_to_string(names: &[Name]) -> String {
3872 let mut first = true;
3873 let mut result = String::new();
3878 result.push_str("::")
3880 result.push_str(&name.as_str());
3885 fn path_names_to_string(path: &Path, depth: usize) -> String {
3886 let names: Vec<ast::Name> = path.segments[..path.segments.len() - depth]
3888 .map(|seg| seg.identifier.name)
3890 names_to_string(&names[..])
3893 /// A somewhat inefficient routine to obtain the name of a module.
3894 fn module_to_string(module: &Module) -> String {
3895 let mut names = Vec::new();
3897 fn collect_mod(names: &mut Vec<ast::Name>, module: &Module) {
3898 match module.parent_link {
3900 ModuleParentLink(ref module, name) => {
3902 collect_mod(names, &*module.upgrade().unwrap());
3904 BlockParentLink(ref module, _) => {
3905 // danger, shouldn't be ident?
3906 names.push(special_idents::opaque.name);
3907 collect_mod(names, &*module.upgrade().unwrap());
3911 collect_mod(&mut names, module);
3913 if names.is_empty() {
3914 return "???".to_string();
3916 names_to_string(&names.into_iter().rev().collect::<Vec<ast::Name>>())
3919 fn err_path_resolution() -> PathResolution {
3922 last_private: LastMod(AllPublic),
3928 pub struct CrateMap {
3929 pub def_map: RefCell<DefMap>,
3930 pub freevars: FreevarMap,
3931 pub export_map: ExportMap,
3932 pub trait_map: TraitMap,
3933 pub external_exports: ExternalExports,
3934 pub glob_map: Option<GlobMap>,
3937 #[derive(PartialEq,Copy, Clone)]
3938 pub enum MakeGlobMap {
3943 /// Entry point to crate resolution.
3944 pub fn resolve_crate<'a, 'tcx>(session: &'a Session,
3945 ast_map: &'a hir_map::Map<'tcx>,
3946 make_glob_map: MakeGlobMap)
3948 let krate = ast_map.krate();
3949 let mut resolver = create_resolver(session, ast_map, krate, make_glob_map, None);
3951 resolver.resolve_crate(krate);
3953 check_unused::check_crate(&mut resolver, krate);
3956 def_map: resolver.def_map,
3957 freevars: resolver.freevars,
3958 export_map: resolver.export_map,
3959 trait_map: resolver.trait_map,
3960 external_exports: resolver.external_exports,
3961 glob_map: if resolver.make_glob_map {
3962 Some(resolver.glob_map)
3969 /// Builds a name resolution walker to be used within this module,
3970 /// or used externally, with an optional callback function.
3972 /// The callback takes a &mut bool which allows callbacks to end a
3973 /// walk when set to true, passing through the rest of the walk, while
3974 /// preserving the ribs + current module. This allows resolve_path
3975 /// calls to be made with the correct scope info. The node in the
3976 /// callback corresponds to the current node in the walk.
3977 pub fn create_resolver<'a, 'tcx>(session: &'a Session,
3978 ast_map: &'a hir_map::Map<'tcx>,
3980 make_glob_map: MakeGlobMap,
3981 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>)
3982 -> Resolver<'a, 'tcx> {
3983 let mut resolver = Resolver::new(session, ast_map, make_glob_map);
3985 resolver.callback = callback;
3987 build_reduced_graph::build_reduced_graph(&mut resolver, krate);
3988 session.abort_if_errors();
3990 resolve_imports::resolve_imports(&mut resolver);
3991 session.abort_if_errors();
3993 record_exports::record(&mut resolver);
3994 session.abort_if_errors();
3999 __build_diagnostic_array! { librustc_resolve, DIAGNOSTICS }