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/")]
18 #![cfg_attr(not(stage0), deny(warnings))]
20 #![feature(associated_consts)]
21 #![feature(borrow_state)]
22 #![feature(rustc_diagnostic_macros)]
23 #![feature(rustc_private)]
24 #![feature(staged_api)]
33 extern crate rustc_bitflags;
34 extern crate rustc_front;
37 use self::PatternBindingMode::*;
38 use self::Namespace::*;
39 use self::ResolveResult::*;
40 use self::FallbackSuggestion::*;
41 use self::TypeParameters::*;
43 use self::UseLexicalScopeFlag::*;
44 use self::ModulePrefixResult::*;
45 use self::AssocItemResolveResult::*;
46 use self::BareIdentifierPatternResolution::*;
47 use self::ParentLink::*;
48 use self::FallbackChecks::*;
50 use rustc::dep_graph::DepNode;
51 use rustc::front::map as hir_map;
52 use rustc::session::Session;
54 use rustc::middle::cstore::{CrateStore, DefLike, DlDef};
55 use rustc::middle::def::*;
56 use rustc::middle::def_id::DefId;
57 use rustc::middle::pat_util::pat_bindings;
58 use rustc::middle::privacy::*;
59 use rustc::middle::subst::{ParamSpace, FnSpace, TypeSpace};
60 use rustc::middle::ty::{Freevar, FreevarMap, TraitMap, GlobMap};
61 use rustc::util::nodemap::{NodeMap, DefIdSet, FnvHashMap};
63 use syntax::ast::{self, FloatTy};
64 use syntax::ast::{CRATE_NODE_ID, Name, NodeId, CrateNum, IntTy, UintTy};
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;
94 use resolve_imports::{ImportDirective, NameResolution};
96 // NB: This module needs to be declared first so diagnostics are
97 // registered before they are used.
101 mod build_reduced_graph;
104 // Perform the callback, not walking deeper if the return is true
105 macro_rules! execute_callback {
106 ($node: expr, $walker: expr) => (
107 if let Some(ref callback) = $walker.callback {
108 if callback($node, &mut $walker.resolved) {
115 enum SuggestionType {
117 Function(token::InternedString),
121 pub enum ResolutionError<'a> {
122 /// error E0401: can't use type parameters from outer function
123 TypeParametersFromOuterFunction,
124 /// error E0402: cannot use an outer type parameter in this context
125 OuterTypeParameterContext,
126 /// error E0403: the name is already used for a type parameter in this type parameter list
127 NameAlreadyUsedInTypeParameterList(Name),
128 /// error E0404: is not a trait
129 IsNotATrait(&'a str),
130 /// error E0405: use of undeclared trait name
131 UndeclaredTraitName(&'a str),
132 /// error E0406: undeclared associated type
133 UndeclaredAssociatedType,
134 /// error E0407: method is not a member of trait
135 MethodNotMemberOfTrait(Name, &'a str),
136 /// error E0437: type is not a member of trait
137 TypeNotMemberOfTrait(Name, &'a str),
138 /// error E0438: const is not a member of trait
139 ConstNotMemberOfTrait(Name, &'a str),
140 /// error E0408: variable `{}` from pattern #1 is not bound in pattern
141 VariableNotBoundInPattern(Name, usize),
142 /// error E0409: variable is bound with different mode in pattern #{} than in pattern #1
143 VariableBoundWithDifferentMode(Name, usize),
144 /// error E0410: variable from pattern is not bound in pattern #1
145 VariableNotBoundInParentPattern(Name, usize),
146 /// error E0411: use of `Self` outside of an impl or trait
147 SelfUsedOutsideImplOrTrait,
148 /// error E0412: use of undeclared
149 UseOfUndeclared(&'a str, &'a str),
150 /// error E0413: declaration shadows an enum variant or unit-like struct in scope
151 DeclarationShadowsEnumVariantOrUnitLikeStruct(Name),
152 /// error E0414: only irrefutable patterns allowed here
153 OnlyIrrefutablePatternsAllowedHere(DefId, Name),
154 /// error E0415: identifier is bound more than once in this parameter list
155 IdentifierBoundMoreThanOnceInParameterList(&'a str),
156 /// error E0416: identifier is bound more than once in the same pattern
157 IdentifierBoundMoreThanOnceInSamePattern(&'a str),
158 /// error E0417: static variables cannot be referenced in a pattern
159 StaticVariableReference,
160 /// error E0418: is not an enum variant, struct or const
161 NotAnEnumVariantStructOrConst(&'a str),
162 /// error E0419: unresolved enum variant, struct or const
163 UnresolvedEnumVariantStructOrConst(&'a str),
164 /// error E0420: is not an associated const
165 NotAnAssociatedConst(&'a str),
166 /// error E0421: unresolved associated const
167 UnresolvedAssociatedConst(&'a str),
168 /// error E0422: does not name a struct
169 DoesNotNameAStruct(&'a str),
170 /// error E0423: is a struct variant name, but this expression uses it like a function name
171 StructVariantUsedAsFunction(&'a str),
172 /// error E0424: `self` is not available in a static method
173 SelfNotAvailableInStaticMethod,
174 /// error E0425: unresolved name
175 UnresolvedName(&'a str, &'a str, UnresolvedNameContext),
176 /// error E0426: use of undeclared label
177 UndeclaredLabel(&'a str),
178 /// error E0427: cannot use `ref` binding mode with ...
179 CannotUseRefBindingModeWith(&'a str),
180 /// error E0428: duplicate definition
181 DuplicateDefinition(&'a str, Name),
182 /// error E0429: `self` imports are only allowed within a { } list
183 SelfImportsOnlyAllowedWithin,
184 /// error E0430: `self` import can only appear once in the list
185 SelfImportCanOnlyAppearOnceInTheList,
186 /// error E0431: `self` import can only appear in an import list with a non-empty prefix
187 SelfImportOnlyInImportListWithNonEmptyPrefix,
188 /// error E0432: unresolved import
189 UnresolvedImport(Option<(&'a str, &'a str)>),
190 /// error E0433: failed to resolve
191 FailedToResolve(&'a str),
192 /// error E0434: can't capture dynamic environment in a fn item
193 CannotCaptureDynamicEnvironmentInFnItem,
194 /// error E0435: attempt to use a non-constant value in a constant
195 AttemptToUseNonConstantValueInConstant,
198 /// Context of where `ResolutionError::UnresolvedName` arose.
199 #[derive(Clone, PartialEq, Eq, Debug)]
200 pub enum UnresolvedNameContext {
201 /// `PathIsMod(id)` indicates that a given path, used in
202 /// expression context, actually resolved to a module rather than
203 /// a value. The `id` attached to the variant is the node id of
204 /// the erroneous path expression.
205 PathIsMod(ast::NodeId),
207 /// `Other` means we have no extra information about the context
208 /// of the unresolved name error. (Maybe we could eliminate all
209 /// such cases; but for now, this is an information-free default.)
213 fn resolve_error<'b, 'a: 'b, 'tcx: 'a>(resolver: &'b Resolver<'a, 'tcx>,
214 span: syntax::codemap::Span,
215 resolution_error: ResolutionError<'b>) {
216 resolve_struct_error(resolver, span, resolution_error).emit();
219 fn resolve_struct_error<'b, 'a: 'b, 'tcx: 'a>(resolver: &'b Resolver<'a, 'tcx>,
220 span: syntax::codemap::Span,
221 resolution_error: ResolutionError<'b>)
222 -> DiagnosticBuilder<'a> {
223 if !resolver.emit_errors {
224 return resolver.session.diagnostic().struct_dummy();
227 match resolution_error {
228 ResolutionError::TypeParametersFromOuterFunction => {
229 struct_span_err!(resolver.session,
232 "can't use type parameters from outer function; try using a local \
233 type parameter instead")
235 ResolutionError::OuterTypeParameterContext => {
236 struct_span_err!(resolver.session,
239 "cannot use an outer type parameter in this context")
241 ResolutionError::NameAlreadyUsedInTypeParameterList(name) => {
242 struct_span_err!(resolver.session,
245 "the name `{}` is already used for a type parameter in this type \
249 ResolutionError::IsNotATrait(name) => {
250 struct_span_err!(resolver.session, span, E0404, "`{}` is not a trait", name)
252 ResolutionError::UndeclaredTraitName(name) => {
253 struct_span_err!(resolver.session,
256 "use of undeclared trait name `{}`",
259 ResolutionError::UndeclaredAssociatedType => {
260 struct_span_err!(resolver.session, span, E0406, "undeclared associated type")
262 ResolutionError::MethodNotMemberOfTrait(method, trait_) => {
263 struct_span_err!(resolver.session,
266 "method `{}` is not a member of trait `{}`",
270 ResolutionError::TypeNotMemberOfTrait(type_, trait_) => {
271 struct_span_err!(resolver.session,
274 "type `{}` is not a member of trait `{}`",
278 ResolutionError::ConstNotMemberOfTrait(const_, trait_) => {
279 struct_span_err!(resolver.session,
282 "const `{}` is not a member of trait `{}`",
286 ResolutionError::VariableNotBoundInPattern(variable_name, pattern_number) => {
287 struct_span_err!(resolver.session,
290 "variable `{}` from pattern #1 is not bound in pattern #{}",
294 ResolutionError::VariableBoundWithDifferentMode(variable_name, pattern_number) => {
295 struct_span_err!(resolver.session,
298 "variable `{}` is bound with different mode in pattern #{} than in \
303 ResolutionError::VariableNotBoundInParentPattern(variable_name, pattern_number) => {
304 struct_span_err!(resolver.session,
307 "variable `{}` from pattern #{} is not bound in pattern #1",
311 ResolutionError::SelfUsedOutsideImplOrTrait => {
312 struct_span_err!(resolver.session,
315 "use of `Self` outside of an impl or trait")
317 ResolutionError::UseOfUndeclared(kind, name) => {
318 struct_span_err!(resolver.session,
321 "use of undeclared {} `{}`",
325 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(name) => {
326 struct_span_err!(resolver.session,
329 "declaration of `{}` shadows an enum variant \
330 or unit-like struct in scope",
333 ResolutionError::OnlyIrrefutablePatternsAllowedHere(did, name) => {
334 let mut err = struct_span_err!(resolver.session,
337 "only irrefutable patterns allowed here");
339 "there already is a constant in scope sharing the same \
340 name as this pattern");
341 if let Some(sp) = resolver.ast_map.span_if_local(did) {
342 err.span_note(sp, "constant defined here");
344 if let Success(binding) = resolver.current_module.resolve_name(name, ValueNS, true) {
345 if binding.is_import() {
346 err.span_note(binding.span.unwrap(), "constant imported here");
351 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(identifier) => {
352 struct_span_err!(resolver.session,
355 "identifier `{}` is bound more than once in this parameter list",
358 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(identifier) => {
359 struct_span_err!(resolver.session,
362 "identifier `{}` is bound more than once in the same pattern",
365 ResolutionError::StaticVariableReference => {
366 struct_span_err!(resolver.session,
369 "static variables cannot be referenced in a pattern, use a \
372 ResolutionError::NotAnEnumVariantStructOrConst(name) => {
373 struct_span_err!(resolver.session,
376 "`{}` is not an enum variant, struct or const",
379 ResolutionError::UnresolvedEnumVariantStructOrConst(name) => {
380 struct_span_err!(resolver.session,
383 "unresolved enum variant, struct or const `{}`",
386 ResolutionError::NotAnAssociatedConst(name) => {
387 struct_span_err!(resolver.session,
390 "`{}` is not an associated const",
393 ResolutionError::UnresolvedAssociatedConst(name) => {
394 struct_span_err!(resolver.session,
397 "unresolved associated const `{}`",
400 ResolutionError::DoesNotNameAStruct(name) => {
401 struct_span_err!(resolver.session,
404 "`{}` does not name a structure",
407 ResolutionError::StructVariantUsedAsFunction(path_name) => {
408 struct_span_err!(resolver.session,
411 "`{}` is the name of a struct or struct variant, but this expression \
412 uses it like a function name",
415 ResolutionError::SelfNotAvailableInStaticMethod => {
416 struct_span_err!(resolver.session,
419 "`self` is not available in a static method. Maybe a `self` \
420 argument is missing?")
422 ResolutionError::UnresolvedName(path, msg, context) => {
423 let mut err = struct_span_err!(resolver.session,
426 "unresolved name `{}`{}",
431 UnresolvedNameContext::Other => { } // no help available
432 UnresolvedNameContext::PathIsMod(id) => {
433 let mut help_msg = String::new();
434 let parent_id = resolver.ast_map.get_parent_node(id);
435 if let Some(hir_map::Node::NodeExpr(e)) = resolver.ast_map.find(parent_id) {
437 ExprField(_, ident) => {
438 help_msg = format!("To reference an item from the \
439 `{module}` module, use \
440 `{module}::{ident}`",
444 ExprMethodCall(ident, _, _) => {
445 help_msg = format!("To call a function from the \
446 `{module}` module, use \
447 `{module}::{ident}(..)`",
452 help_msg = format!("No function corresponds to `{module}(..)`",
455 _ => { } // no help available
458 help_msg = format!("Module `{module}` cannot be the value of an expression",
462 if !help_msg.is_empty() {
463 err.fileline_help(span, &help_msg);
469 ResolutionError::UndeclaredLabel(name) => {
470 struct_span_err!(resolver.session,
473 "use of undeclared label `{}`",
476 ResolutionError::CannotUseRefBindingModeWith(descr) => {
477 struct_span_err!(resolver.session,
480 "cannot use `ref` binding mode with {}",
483 ResolutionError::DuplicateDefinition(namespace, name) => {
484 struct_span_err!(resolver.session,
487 "duplicate definition of {} `{}`",
491 ResolutionError::SelfImportsOnlyAllowedWithin => {
492 struct_span_err!(resolver.session,
496 "`self` imports are only allowed within a { } list")
498 ResolutionError::SelfImportCanOnlyAppearOnceInTheList => {
499 struct_span_err!(resolver.session,
502 "`self` import can only appear once in the list")
504 ResolutionError::SelfImportOnlyInImportListWithNonEmptyPrefix => {
505 struct_span_err!(resolver.session,
508 "`self` import can only appear in an import list with a \
511 ResolutionError::UnresolvedImport(name) => {
512 let msg = match name {
513 Some((n, p)) => format!("unresolved import `{}`{}", n, p),
514 None => "unresolved import".to_owned(),
516 struct_span_err!(resolver.session, span, E0432, "{}", msg)
518 ResolutionError::FailedToResolve(msg) => {
519 struct_span_err!(resolver.session, span, E0433, "failed to resolve. {}", msg)
521 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem => {
522 struct_span_err!(resolver.session,
526 "can't capture dynamic environment in a fn item; use the || { ... } \
527 closure form instead")
529 ResolutionError::AttemptToUseNonConstantValueInConstant => {
530 struct_span_err!(resolver.session,
533 "attempt to use a non-constant value in a constant")
538 #[derive(Copy, Clone)]
541 binding_mode: BindingMode,
544 // Map from the name in a pattern to its binding mode.
545 type BindingMap = HashMap<Name, BindingInfo>;
547 #[derive(Copy, Clone, PartialEq)]
548 enum PatternBindingMode {
550 LocalIrrefutableMode,
551 ArgumentIrrefutableMode,
554 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
560 impl<'a, 'v, 'tcx> Visitor<'v> for Resolver<'a, 'tcx> {
561 fn visit_nested_item(&mut self, item: hir::ItemId) {
562 self.visit_item(self.ast_map.expect_item(item.id))
564 fn visit_item(&mut self, item: &Item) {
565 execute_callback!(hir_map::Node::NodeItem(item), self);
566 self.resolve_item(item);
568 fn visit_arm(&mut self, arm: &Arm) {
569 self.resolve_arm(arm);
571 fn visit_block(&mut self, block: &Block) {
572 execute_callback!(hir_map::Node::NodeBlock(block), self);
573 self.resolve_block(block);
575 fn visit_expr(&mut self, expr: &Expr) {
576 execute_callback!(hir_map::Node::NodeExpr(expr), self);
577 self.resolve_expr(expr);
579 fn visit_local(&mut self, local: &Local) {
580 execute_callback!(hir_map::Node::NodeLocal(&local.pat), self);
581 self.resolve_local(local);
583 fn visit_ty(&mut self, ty: &Ty) {
584 self.resolve_type(ty);
586 fn visit_generics(&mut self, generics: &Generics) {
587 self.resolve_generics(generics);
589 fn visit_poly_trait_ref(&mut self, tref: &hir::PolyTraitRef, m: &hir::TraitBoundModifier) {
590 match self.resolve_trait_reference(tref.trait_ref.ref_id, &tref.trait_ref.path, 0) {
591 Ok(def) => self.record_def(tref.trait_ref.ref_id, def),
593 // error already reported
594 self.record_def(tref.trait_ref.ref_id, err_path_resolution())
597 intravisit::walk_poly_trait_ref(self, tref, m);
599 fn visit_variant(&mut self,
600 variant: &hir::Variant,
602 item_id: ast::NodeId) {
603 execute_callback!(hir_map::Node::NodeVariant(variant), self);
604 if let Some(ref dis_expr) = variant.node.disr_expr {
605 // resolve the discriminator expr as a constant
606 self.with_constant_rib(|this| {
607 this.visit_expr(dis_expr);
611 // `intravisit::walk_variant` without the discriminant expression.
612 self.visit_variant_data(&variant.node.data,
618 fn visit_foreign_item(&mut self, foreign_item: &hir::ForeignItem) {
619 execute_callback!(hir_map::Node::NodeForeignItem(foreign_item), self);
620 let type_parameters = match foreign_item.node {
621 ForeignItemFn(_, ref generics) => {
622 HasTypeParameters(generics, FnSpace, ItemRibKind)
624 ForeignItemStatic(..) => NoTypeParameters,
626 self.with_type_parameter_rib(type_parameters, |this| {
627 intravisit::walk_foreign_item(this, foreign_item);
630 fn visit_fn(&mut self,
631 function_kind: FnKind<'v>,
632 declaration: &'v FnDecl,
636 let rib_kind = match function_kind {
637 FnKind::ItemFn(_, generics, _, _, _, _) => {
638 self.visit_generics(generics);
641 FnKind::Method(_, sig, _) => {
642 self.visit_generics(&sig.generics);
643 self.visit_explicit_self(&sig.explicit_self);
646 FnKind::Closure => ClosureRibKind(node_id),
648 self.resolve_function(rib_kind, declaration, block);
652 pub type ErrorMessage = Option<(Span, String)>;
654 #[derive(Clone, PartialEq, Eq)]
655 pub enum ResolveResult<T> {
656 Failed(ErrorMessage), // Failed to resolve the name, optional helpful error message.
657 Indeterminate, // Couldn't determine due to unresolved globs.
658 Success(T), // Successfully resolved the import.
661 impl<T> ResolveResult<T> {
662 fn and_then<U, F: FnOnce(T) -> ResolveResult<U>>(self, f: F) -> ResolveResult<U> {
664 Failed(msg) => Failed(msg),
665 Indeterminate => Indeterminate,
670 fn success(self) -> Option<T> {
672 Success(t) => Some(t),
678 enum FallbackSuggestion {
683 StaticMethod(String),
687 #[derive(Copy, Clone)]
688 enum TypeParameters<'tcx, 'a> {
690 HasTypeParameters(// Type parameters.
693 // Identifies the things that these parameters
694 // were declared on (type, fn, etc)
697 // The kind of the rib used for type parameters.
701 // The rib kind controls the translation of local
702 // definitions (`Def::Local`) to upvars (`Def::Upvar`).
703 #[derive(Copy, Clone, Debug)]
705 // No translation needs to be applied.
708 // We passed through a closure scope at the given node ID.
709 // Translate upvars as appropriate.
710 ClosureRibKind(NodeId /* func id */),
712 // We passed through an impl or trait and are now in one of its
713 // methods. Allow references to ty params that impl or trait
714 // binds. Disallow any other upvars (including other ty params that are
718 // We passed through an item scope. Disallow upvars.
721 // We're in a constant item. Can't refer to dynamic stuff.
724 // We passed through an anonymous module.
725 AnonymousModuleRibKind(Module<'a>),
728 #[derive(Copy, Clone)]
729 enum UseLexicalScopeFlag {
734 enum ModulePrefixResult<'a> {
736 PrefixFound(Module<'a>, usize),
739 #[derive(Copy, Clone)]
740 enum AssocItemResolveResult {
741 /// Syntax such as `<T>::item`, which can't be resolved until type
744 /// We should have been able to resolve the associated item.
745 ResolveAttempt(Option<PathResolution>),
748 #[derive(Copy, Clone)]
749 enum BareIdentifierPatternResolution {
750 FoundStructOrEnumVariant(Def, LastPrivate),
751 FoundConst(Def, LastPrivate, Name),
752 BareIdentifierPatternUnresolved,
758 bindings: HashMap<Name, DefLike>,
763 fn new(kind: RibKind<'a>) -> Rib<'a> {
765 bindings: HashMap::new(),
771 /// A definition along with the index of the rib it was found on
773 ribs: Option<(Namespace, usize)>,
778 fn from_def(def: Def) -> Self {
786 /// The link from a module up to its nearest parent node.
787 #[derive(Clone,Debug)]
788 enum ParentLink<'a> {
790 ModuleParentLink(Module<'a>, Name),
791 BlockParentLink(Module<'a>, NodeId),
794 /// One node in the tree of modules.
795 pub struct ModuleS<'a> {
796 parent_link: ParentLink<'a>,
799 is_extern_crate: bool,
801 resolutions: RefCell<HashMap<(Name, Namespace), NameResolution<'a>>>,
802 imports: RefCell<Vec<ImportDirective>>,
804 // The anonymous children of this node. Anonymous children are pseudo-
805 // modules that are implicitly created around items contained within
808 // For example, if we have this:
816 // There will be an anonymous module created around `g` with the ID of the
817 // entry block for `f`.
818 anonymous_children: RefCell<NodeMap<Module<'a>>>,
820 shadowed_traits: RefCell<Vec<&'a NameBinding<'a>>>,
822 // The number of unresolved globs that this module exports.
823 glob_count: Cell<usize>,
825 // The number of unresolved pub imports (both regular and globs) in this module
826 pub_count: Cell<usize>,
828 // The number of unresolved pub glob imports in this module
829 pub_glob_count: Cell<usize>,
831 // The index of the import we're resolving.
832 resolved_import_count: Cell<usize>,
834 // Whether this module is populated. If not populated, any attempt to
835 // access the children must be preceded with a
836 // `populate_module_if_necessary` call.
837 populated: Cell<bool>,
840 pub type Module<'a> = &'a ModuleS<'a>;
842 impl<'a> ModuleS<'a> {
843 fn new(parent_link: ParentLink<'a>, def: Option<Def>, external: bool, is_public: bool) -> Self {
845 parent_link: parent_link,
847 is_public: is_public,
848 is_extern_crate: false,
849 resolutions: RefCell::new(HashMap::new()),
850 imports: RefCell::new(Vec::new()),
851 anonymous_children: RefCell::new(NodeMap()),
852 shadowed_traits: RefCell::new(Vec::new()),
853 glob_count: Cell::new(0),
854 pub_count: Cell::new(0),
855 pub_glob_count: Cell::new(0),
856 resolved_import_count: Cell::new(0),
857 populated: Cell::new(!external),
861 fn resolve_name(&self, name: Name, ns: Namespace, allow_private_imports: bool)
862 -> ResolveResult<&'a NameBinding<'a>> {
864 if allow_private_imports { self.glob_count.get() } else { self.pub_glob_count.get() };
866 self.resolutions.borrow().get(&(name, ns)).cloned().unwrap_or_default().result(glob_count)
867 .and_then(|binding| {
868 let allowed = allow_private_imports || !binding.is_import() || binding.is_public();
869 if allowed { Success(binding) } else { Failed(None) }
873 // Define the name or return the existing binding if there is a collision.
874 fn try_define_child(&self, name: Name, ns: Namespace, binding: &'a NameBinding<'a>)
875 -> Result<(), &'a NameBinding<'a>> {
876 let mut children = self.resolutions.borrow_mut();
877 let resolution = children.entry((name, ns)).or_insert_with(Default::default);
879 // FIXME #31379: We can use methods from imported traits shadowed by non-import items
880 if let Some(old_binding) = resolution.binding {
881 if !old_binding.is_import() && binding.is_import() {
882 if let Some(Def::Trait(_)) = binding.def() {
883 self.shadowed_traits.borrow_mut().push(binding);
888 resolution.try_define(binding)
891 fn increment_outstanding_references_for(&self, name: Name, ns: Namespace) {
892 let mut children = self.resolutions.borrow_mut();
893 children.entry((name, ns)).or_insert_with(Default::default).outstanding_references += 1;
896 fn decrement_outstanding_references_for(&self, name: Name, ns: Namespace) {
897 match self.resolutions.borrow_mut().get_mut(&(name, ns)).unwrap().outstanding_references {
898 0 => panic!("No more outstanding references!"),
899 ref mut outstanding_references => { *outstanding_references -= 1; }
903 fn for_each_child<F: FnMut(Name, Namespace, &'a NameBinding<'a>)>(&self, mut f: F) {
904 for (&(name, ns), name_resolution) in self.resolutions.borrow().iter() {
905 name_resolution.binding.map(|binding| f(name, ns, binding));
909 fn for_each_local_child<F: FnMut(Name, Namespace, &'a NameBinding<'a>)>(&self, mut f: F) {
910 self.for_each_child(|name, ns, name_binding| {
911 if !name_binding.is_import() && !name_binding.is_extern_crate() {
912 f(name, ns, name_binding)
917 fn def_id(&self) -> Option<DefId> {
918 self.def.as_ref().map(Def::def_id)
921 fn is_normal(&self) -> bool {
923 Some(Def::Mod(_)) | Some(Def::ForeignMod(_)) => true,
928 fn is_trait(&self) -> bool {
930 Some(Def::Trait(_)) => true,
935 fn all_imports_resolved(&self) -> bool {
936 if self.imports.borrow_state() == ::std::cell::BorrowState::Writing {
937 // it is currently being resolved ! so nope
940 self.imports.borrow().len() == self.resolved_import_count.get()
944 pub fn inc_glob_count(&self) {
945 self.glob_count.set(self.glob_count.get() + 1);
947 pub fn dec_glob_count(&self) {
948 assert!(self.glob_count.get() > 0);
949 self.glob_count.set(self.glob_count.get() - 1);
951 pub fn inc_pub_count(&self) {
952 self.pub_count.set(self.pub_count.get() + 1);
954 pub fn dec_pub_count(&self) {
955 assert!(self.pub_count.get() > 0);
956 self.pub_count.set(self.pub_count.get() - 1);
958 pub fn inc_pub_glob_count(&self) {
959 self.pub_glob_count.set(self.pub_glob_count.get() + 1);
961 pub fn dec_pub_glob_count(&self) {
962 assert!(self.pub_glob_count.get() > 0);
963 self.pub_glob_count.set(self.pub_glob_count.get() - 1);
967 impl<'a> fmt::Debug for ModuleS<'a> {
968 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
982 flags DefModifiers: u8 {
983 // Enum variants are always considered `PUBLIC`, this is needed for `use Enum::Variant`
984 // or `use Enum::*` to work on private enums.
985 const PUBLIC = 1 << 0,
986 const IMPORTABLE = 1 << 1,
987 // Variants are considered `PUBLIC`, but some of them live in private enums.
988 // We need to track them to prohibit reexports like `pub use PrivEnum::Variant`.
989 const PRIVATE_VARIANT = 1 << 2,
990 const PRELUDE = 1 << 3,
991 const GLOB_IMPORTED = 1 << 4,
995 // Records a possibly-private value, type, or module definition.
997 pub struct NameBinding<'a> {
998 modifiers: DefModifiers,
999 kind: NameBindingKind<'a>,
1004 enum NameBindingKind<'a> {
1008 binding: &'a NameBinding<'a>,
1013 impl<'a> NameBinding<'a> {
1014 fn create_from_module(module: Module<'a>, span: Option<Span>) -> Self {
1015 let modifiers = if module.is_public {
1016 DefModifiers::PUBLIC
1018 DefModifiers::empty()
1019 } | DefModifiers::IMPORTABLE;
1021 NameBinding { modifiers: modifiers, kind: NameBindingKind::Module(module), span: span }
1024 fn module(&self) -> Option<Module<'a>> {
1026 NameBindingKind::Module(module) => Some(module),
1027 NameBindingKind::Def(_) => None,
1028 NameBindingKind::Import { binding, .. } => binding.module(),
1032 fn def(&self) -> Option<Def> {
1034 NameBindingKind::Def(def) => Some(def),
1035 NameBindingKind::Module(module) => module.def,
1036 NameBindingKind::Import { binding, .. } => binding.def(),
1040 fn defined_with(&self, modifiers: DefModifiers) -> bool {
1041 self.modifiers.contains(modifiers)
1044 fn is_public(&self) -> bool {
1045 self.defined_with(DefModifiers::PUBLIC)
1048 fn def_and_lp(&self) -> (Def, LastPrivate) {
1049 let def = self.def().unwrap();
1050 (def, LastMod(if self.is_public() { AllPublic } else { DependsOn(def.def_id()) }))
1053 fn is_extern_crate(&self) -> bool {
1054 self.module().map(|module| module.is_extern_crate).unwrap_or(false)
1057 fn is_import(&self) -> bool {
1059 NameBindingKind::Import { .. } => true,
1065 /// Interns the names of the primitive types.
1066 struct PrimitiveTypeTable {
1067 primitive_types: HashMap<Name, PrimTy>,
1070 impl PrimitiveTypeTable {
1071 fn new() -> PrimitiveTypeTable {
1072 let mut table = PrimitiveTypeTable { primitive_types: HashMap::new() };
1074 table.intern("bool", TyBool);
1075 table.intern("char", TyChar);
1076 table.intern("f32", TyFloat(FloatTy::F32));
1077 table.intern("f64", TyFloat(FloatTy::F64));
1078 table.intern("isize", TyInt(IntTy::Is));
1079 table.intern("i8", TyInt(IntTy::I8));
1080 table.intern("i16", TyInt(IntTy::I16));
1081 table.intern("i32", TyInt(IntTy::I32));
1082 table.intern("i64", TyInt(IntTy::I64));
1083 table.intern("str", TyStr);
1084 table.intern("usize", TyUint(UintTy::Us));
1085 table.intern("u8", TyUint(UintTy::U8));
1086 table.intern("u16", TyUint(UintTy::U16));
1087 table.intern("u32", TyUint(UintTy::U32));
1088 table.intern("u64", TyUint(UintTy::U64));
1093 fn intern(&mut self, string: &str, primitive_type: PrimTy) {
1094 self.primitive_types.insert(token::intern(string), primitive_type);
1098 /// The main resolver class.
1099 pub struct Resolver<'a, 'tcx: 'a> {
1100 session: &'a Session,
1102 ast_map: &'a hir_map::Map<'tcx>,
1104 graph_root: Module<'a>,
1106 trait_item_map: FnvHashMap<(Name, DefId), DefId>,
1108 structs: FnvHashMap<DefId, Vec<Name>>,
1110 // The number of imports that are currently unresolved.
1111 unresolved_imports: usize,
1113 // The module that represents the current item scope.
1114 current_module: Module<'a>,
1116 // The current set of local scopes, for values.
1117 // FIXME #4948: Reuse ribs to avoid allocation.
1118 value_ribs: Vec<Rib<'a>>,
1120 // The current set of local scopes, for types.
1121 type_ribs: Vec<Rib<'a>>,
1123 // The current set of local scopes, for labels.
1124 label_ribs: Vec<Rib<'a>>,
1126 // The trait that the current context can refer to.
1127 current_trait_ref: Option<(DefId, TraitRef)>,
1129 // The current self type if inside an impl (used for better errors).
1130 current_self_type: Option<Ty>,
1132 // The idents for the primitive types.
1133 primitive_type_table: PrimitiveTypeTable,
1135 def_map: RefCell<DefMap>,
1136 freevars: FreevarMap,
1137 freevars_seen: NodeMap<NodeMap<usize>>,
1138 export_map: ExportMap,
1139 trait_map: TraitMap,
1140 external_exports: ExternalExports,
1142 // Whether or not to print error messages. Can be set to true
1143 // when getting additional info for error message suggestions,
1144 // so as to avoid printing duplicate errors
1147 make_glob_map: bool,
1148 // Maps imports to the names of items actually imported (this actually maps
1149 // all imports, but only glob imports are actually interesting).
1152 used_imports: HashSet<(NodeId, Namespace)>,
1153 used_crates: HashSet<CrateNum>,
1155 // Callback function for intercepting walks
1156 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>,
1157 // The intention is that the callback modifies this flag.
1158 // Once set, the resolver falls out of the walk, preserving the ribs.
1161 arenas: &'a ResolverArenas<'a>,
1164 pub struct ResolverArenas<'a> {
1165 modules: arena::TypedArena<ModuleS<'a>>,
1166 name_bindings: arena::TypedArena<NameBinding<'a>>,
1169 #[derive(PartialEq)]
1170 enum FallbackChecks {
1172 OnlyTraitAndStatics,
1175 impl<'a, 'tcx> Resolver<'a, 'tcx> {
1176 fn new(session: &'a Session,
1177 ast_map: &'a hir_map::Map<'tcx>,
1178 make_glob_map: MakeGlobMap,
1179 arenas: &'a ResolverArenas<'a>)
1180 -> Resolver<'a, 'tcx> {
1181 let root_def_id = ast_map.local_def_id(CRATE_NODE_ID);
1182 let graph_root = ModuleS::new(NoParentLink, Some(Def::Mod(root_def_id)), false, true);
1183 let graph_root = arenas.modules.alloc(graph_root);
1190 // The outermost module has def ID 0; this is not reflected in the
1192 graph_root: graph_root,
1194 trait_item_map: FnvHashMap(),
1195 structs: FnvHashMap(),
1197 unresolved_imports: 0,
1199 current_module: graph_root,
1200 value_ribs: Vec::new(),
1201 type_ribs: Vec::new(),
1202 label_ribs: Vec::new(),
1204 current_trait_ref: None,
1205 current_self_type: None,
1207 primitive_type_table: PrimitiveTypeTable::new(),
1209 def_map: RefCell::new(NodeMap()),
1210 freevars: NodeMap(),
1211 freevars_seen: NodeMap(),
1212 export_map: NodeMap(),
1213 trait_map: NodeMap(),
1214 used_imports: HashSet::new(),
1215 used_crates: HashSet::new(),
1216 external_exports: DefIdSet(),
1219 make_glob_map: make_glob_map == MakeGlobMap::Yes,
1220 glob_map: HashMap::new(),
1229 fn arenas() -> ResolverArenas<'a> {
1231 modules: arena::TypedArena::new(),
1232 name_bindings: arena::TypedArena::new(),
1236 fn new_module(&self,
1237 parent_link: ParentLink<'a>,
1240 is_public: bool) -> Module<'a> {
1241 self.arenas.modules.alloc(ModuleS::new(parent_link, def, external, is_public))
1244 fn new_name_binding(&self, name_binding: NameBinding<'a>) -> &'a NameBinding<'a> {
1245 self.arenas.name_bindings.alloc(name_binding)
1248 fn new_extern_crate_module(&self, parent_link: ParentLink<'a>, def: Def) -> Module<'a> {
1249 let mut module = ModuleS::new(parent_link, Some(def), false, true);
1250 module.is_extern_crate = true;
1251 self.arenas.modules.alloc(module)
1254 fn get_ribs<'b>(&'b mut self, ns: Namespace) -> &'b mut Vec<Rib<'a>> {
1255 match ns { ValueNS => &mut self.value_ribs, TypeNS => &mut self.type_ribs }
1259 fn record_use(&mut self, name: Name, ns: Namespace, binding: &'a NameBinding<'a>) {
1260 // track extern crates for unused_extern_crate lint
1261 if let Some(DefId { krate, .. }) = binding.module().and_then(ModuleS::def_id) {
1262 self.used_crates.insert(krate);
1265 let import_id = match binding.kind {
1266 NameBindingKind::Import { id, .. } => id,
1270 self.used_imports.insert((import_id, ns));
1272 if !self.make_glob_map {
1275 if self.glob_map.contains_key(&import_id) {
1276 self.glob_map.get_mut(&import_id).unwrap().insert(name);
1280 let mut new_set = HashSet::new();
1281 new_set.insert(name);
1282 self.glob_map.insert(import_id, new_set);
1285 fn get_trait_name(&self, did: DefId) -> Name {
1286 if let Some(node_id) = self.ast_map.as_local_node_id(did) {
1287 self.ast_map.expect_item(node_id).name
1289 self.session.cstore.item_name(did)
1293 /// Resolves the given module path from the given root `module_`.
1294 fn resolve_module_path_from_root(&mut self,
1295 module_: Module<'a>,
1296 module_path: &[Name],
1300 -> ResolveResult<(Module<'a>, LastPrivate)> {
1301 fn search_parent_externals<'a>(needle: Name, module: Module<'a>) -> Option<Module<'a>> {
1302 match module.resolve_name(needle, TypeNS, false) {
1303 Success(binding) if binding.is_extern_crate() => Some(module),
1304 _ => match module.parent_link {
1305 ModuleParentLink(ref parent, _) => {
1306 search_parent_externals(needle, parent)
1313 let mut search_module = module_;
1314 let mut index = index;
1315 let module_path_len = module_path.len();
1316 let mut closest_private = lp;
1318 // Resolve the module part of the path. This does not involve looking
1319 // upward though scope chains; we simply resolve names directly in
1320 // modules as we go.
1321 while index < module_path_len {
1322 let name = module_path[index];
1323 match self.resolve_name_in_module(search_module, name, TypeNS, false, true) {
1325 let segment_name = name.as_str();
1326 let module_name = module_to_string(search_module);
1327 let mut span = span;
1328 let msg = if "???" == &module_name {
1329 span.hi = span.lo + Pos::from_usize(segment_name.len());
1331 match search_parent_externals(name, &self.current_module) {
1333 let path_str = names_to_string(module_path);
1334 let target_mod_str = module_to_string(&module);
1335 let current_mod_str = module_to_string(&self.current_module);
1337 let prefix = if target_mod_str == current_mod_str {
1338 "self::".to_string()
1340 format!("{}::", target_mod_str)
1343 format!("Did you mean `{}{}`?", prefix, path_str)
1345 None => format!("Maybe a missing `extern crate {}`?", segment_name),
1348 format!("Could not find `{}` in `{}`", segment_name, module_name)
1351 return Failed(Some((span, msg)));
1353 Failed(err) => return Failed(err),
1355 debug!("(resolving module path for import) module resolution is \
1358 return Indeterminate;
1360 Success(binding) => {
1361 // Check to see whether there are type bindings, and, if
1362 // so, whether there is a module within.
1363 if let Some(module_def) = binding.module() {
1364 search_module = module_def;
1366 // Keep track of the closest private module used
1367 // when resolving this import chain.
1368 if !binding.is_public() {
1369 if let Some(did) = search_module.def_id() {
1370 closest_private = LastMod(DependsOn(did));
1374 let msg = format!("Not a module `{}`", name);
1375 return Failed(Some((span, msg)));
1383 return Success((search_module, closest_private));
1386 /// Attempts to resolve the module part of an import directive or path
1387 /// rooted at the given module.
1389 /// On success, returns the resolved module, and the closest *private*
1390 /// module found to the destination when resolving this path.
1391 fn resolve_module_path(&mut self,
1392 module_: Module<'a>,
1393 module_path: &[Name],
1394 use_lexical_scope: UseLexicalScopeFlag,
1396 -> ResolveResult<(Module<'a>, LastPrivate)> {
1397 if module_path.len() == 0 {
1398 return Success((self.graph_root, LastMod(AllPublic))) // Use the crate root
1401 debug!("(resolving module path for import) processing `{}` rooted at `{}`",
1402 names_to_string(module_path),
1403 module_to_string(&module_));
1405 // Resolve the module prefix, if any.
1406 let module_prefix_result = self.resolve_module_prefix(module_, module_path);
1411 match module_prefix_result {
1413 let mpath = names_to_string(module_path);
1414 let mpath = &mpath[..];
1415 match mpath.rfind(':') {
1417 let msg = format!("Could not find `{}` in `{}`",
1418 // idx +- 1 to account for the
1419 // colons on either side
1422 return Failed(Some((span, msg)));
1425 return Failed(None);
1429 Failed(err) => return Failed(err),
1431 debug!("(resolving module path for import) indeterminate; bailing");
1432 return Indeterminate;
1434 Success(NoPrefixFound) => {
1435 // There was no prefix, so we're considering the first element
1436 // of the path. How we handle this depends on whether we were
1437 // instructed to use lexical scope or not.
1438 match use_lexical_scope {
1439 DontUseLexicalScope => {
1440 // This is a crate-relative path. We will start the
1441 // resolution process at index zero.
1442 search_module = self.graph_root;
1444 last_private = LastMod(AllPublic);
1446 UseLexicalScope => {
1447 // This is not a crate-relative path. We resolve the
1448 // first component of the path in the current lexical
1449 // scope and then proceed to resolve below that.
1450 match self.resolve_item_in_lexical_scope(module_,
1454 Failed(err) => return Failed(err),
1456 debug!("(resolving module path for import) indeterminate; bailing");
1457 return Indeterminate;
1459 Success(binding) => match binding.module() {
1460 Some(containing_module) => {
1461 search_module = containing_module;
1463 last_private = LastMod(AllPublic);
1465 None => return Failed(None),
1471 Success(PrefixFound(ref containing_module, index)) => {
1472 search_module = containing_module;
1473 start_index = index;
1474 last_private = LastMod(DependsOn(containing_module.def_id()
1479 self.resolve_module_path_from_root(search_module,
1486 /// Invariant: This must only be called during main resolution, not during
1487 /// import resolution.
1488 fn resolve_item_in_lexical_scope(&mut self,
1489 module_: Module<'a>,
1491 namespace: Namespace,
1493 -> ResolveResult<&'a NameBinding<'a>> {
1494 debug!("(resolving item in lexical scope) resolving `{}` in namespace {:?} in `{}`",
1497 module_to_string(&module_));
1499 // Proceed up the scope chain looking for parent modules.
1500 let mut search_module = module_;
1502 // Resolve the name in the parent module.
1503 match self.resolve_name_in_module(search_module, name, namespace, true, record_used) {
1504 Failed(Some((span, msg))) => {
1505 resolve_error(self, span, ResolutionError::FailedToResolve(&msg));
1507 Failed(None) => (), // Continue up the search chain.
1509 // We couldn't see through the higher scope because of an
1510 // unresolved import higher up. Bail.
1512 debug!("(resolving item in lexical scope) indeterminate higher scope; bailing");
1513 return Indeterminate;
1515 Success(binding) => {
1516 // We found the module.
1517 debug!("(resolving item in lexical scope) found name in module, done");
1518 return Success(binding);
1522 // Go to the next parent.
1523 match search_module.parent_link {
1525 // No more parents. This module was unresolved.
1526 debug!("(resolving item in lexical scope) unresolved module: no parent module");
1527 return Failed(None);
1529 ModuleParentLink(parent_module_node, _) => {
1530 if search_module.is_normal() {
1531 // We stop the search here.
1532 debug!("(resolving item in lexical scope) unresolved module: not \
1533 searching through module parents");
1534 return Failed(None);
1536 search_module = parent_module_node;
1539 BlockParentLink(parent_module_node, _) => {
1540 search_module = parent_module_node;
1546 /// Returns the nearest normal module parent of the given module.
1547 fn get_nearest_normal_module_parent(&mut self, module_: Module<'a>) -> Option<Module<'a>> {
1548 let mut module_ = module_;
1550 match module_.parent_link {
1551 NoParentLink => return None,
1552 ModuleParentLink(new_module, _) |
1553 BlockParentLink(new_module, _) => {
1554 let new_module = new_module;
1555 if new_module.is_normal() {
1556 return Some(new_module);
1558 module_ = new_module;
1564 /// Returns the nearest normal module parent of the given module, or the
1565 /// module itself if it is a normal module.
1566 fn get_nearest_normal_module_parent_or_self(&mut self, module_: Module<'a>) -> Module<'a> {
1567 if module_.is_normal() {
1570 match self.get_nearest_normal_module_parent(module_) {
1572 Some(new_module) => new_module,
1576 /// Resolves a "module prefix". A module prefix is one or both of (a) `self::`;
1577 /// (b) some chain of `super::`.
1578 /// grammar: (SELF MOD_SEP ) ? (SUPER MOD_SEP) *
1579 fn resolve_module_prefix(&mut self,
1580 module_: Module<'a>,
1581 module_path: &[Name])
1582 -> ResolveResult<ModulePrefixResult<'a>> {
1583 // Start at the current module if we see `self` or `super`, or at the
1584 // top of the crate otherwise.
1585 let mut i = match &*module_path[0].as_str() {
1588 _ => return Success(NoPrefixFound),
1590 let mut containing_module = self.get_nearest_normal_module_parent_or_self(module_);
1592 // Now loop through all the `super`s we find.
1593 while i < module_path.len() && "super" == module_path[i].as_str() {
1594 debug!("(resolving module prefix) resolving `super` at {}",
1595 module_to_string(&containing_module));
1596 match self.get_nearest_normal_module_parent(containing_module) {
1597 None => return Failed(None),
1598 Some(new_module) => {
1599 containing_module = new_module;
1605 debug!("(resolving module prefix) finished resolving prefix at {}",
1606 module_to_string(&containing_module));
1608 return Success(PrefixFound(containing_module, i));
1611 /// Attempts to resolve the supplied name in the given module for the
1612 /// given namespace. If successful, returns the binding corresponding to
1614 fn resolve_name_in_module(&mut self,
1617 namespace: Namespace,
1618 allow_private_imports: bool,
1620 -> ResolveResult<&'a NameBinding<'a>> {
1621 debug!("(resolving name in module) resolving `{}` in `{}`", name, module_to_string(module));
1623 build_reduced_graph::populate_module_if_necessary(self, module);
1624 module.resolve_name(name, namespace, allow_private_imports).and_then(|binding| {
1626 self.record_use(name, namespace, binding);
1632 fn report_unresolved_imports(&mut self, module_: Module<'a>) {
1633 let index = module_.resolved_import_count.get();
1634 let imports = module_.imports.borrow();
1635 let import_count = imports.len();
1636 if index != import_count {
1638 (*imports)[index].span,
1639 ResolutionError::UnresolvedImport(None));
1642 // Descend into children and anonymous children.
1643 build_reduced_graph::populate_module_if_necessary(self, module_);
1645 module_.for_each_local_child(|_, _, child_node| {
1646 match child_node.module() {
1650 Some(child_module) => {
1651 self.report_unresolved_imports(child_module);
1656 for (_, module_) in module_.anonymous_children.borrow().iter() {
1657 self.report_unresolved_imports(module_);
1663 // We maintain a list of value ribs and type ribs.
1665 // Simultaneously, we keep track of the current position in the module
1666 // graph in the `current_module` pointer. When we go to resolve a name in
1667 // the value or type namespaces, we first look through all the ribs and
1668 // then query the module graph. When we resolve a name in the module
1669 // namespace, we can skip all the ribs (since nested modules are not
1670 // allowed within blocks in Rust) and jump straight to the current module
1673 // Named implementations are handled separately. When we find a method
1674 // call, we consult the module node to find all of the implementations in
1675 // scope. This information is lazily cached in the module node. We then
1676 // generate a fake "implementation scope" containing all the
1677 // implementations thus found, for compatibility with old resolve pass.
1679 fn with_scope<F>(&mut self, name: Option<Name>, f: F)
1680 where F: FnOnce(&mut Resolver)
1682 let orig_module = self.current_module;
1684 // Move down in the graph.
1690 build_reduced_graph::populate_module_if_necessary(self, &orig_module);
1692 if let Success(name_binding) = orig_module.resolve_name(name, TypeNS, false) {
1693 match name_binding.module() {
1695 debug!("!!! (with scope) didn't find module for `{}` in `{}`",
1697 module_to_string(orig_module));
1700 self.current_module = module;
1709 self.current_module = orig_module;
1712 /// Searches the current set of local scopes for labels.
1713 /// Stops after meeting a closure.
1714 fn search_label(&self, name: Name) -> Option<DefLike> {
1715 for rib in self.label_ribs.iter().rev() {
1721 // Do not resolve labels across function boundary
1725 let result = rib.bindings.get(&name).cloned();
1726 if result.is_some() {
1733 fn resolve_crate(&mut self, krate: &hir::Crate) {
1734 debug!("(resolving crate) starting");
1736 intravisit::walk_crate(self, krate);
1739 fn check_if_primitive_type_name(&self, name: Name, span: Span) {
1740 if let Some(_) = self.primitive_type_table.primitive_types.get(&name) {
1741 span_err!(self.session,
1744 "user-defined types or type parameters cannot shadow the primitive types");
1748 fn resolve_item(&mut self, item: &Item) {
1749 let name = item.name;
1751 debug!("(resolving item) resolving {}", name);
1754 ItemEnum(_, ref generics) |
1755 ItemTy(_, ref generics) |
1756 ItemStruct(_, ref generics) => {
1757 self.check_if_primitive_type_name(name, item.span);
1759 self.with_type_parameter_rib(HasTypeParameters(generics, TypeSpace, ItemRibKind),
1760 |this| intravisit::walk_item(this, item));
1762 ItemFn(_, _, _, _, ref generics, _) => {
1763 self.with_type_parameter_rib(HasTypeParameters(generics, FnSpace, ItemRibKind),
1764 |this| intravisit::walk_item(this, item));
1767 ItemDefaultImpl(_, ref trait_ref) => {
1768 self.with_optional_trait_ref(Some(trait_ref), |_, _| {});
1770 ItemImpl(_, _, ref generics, ref opt_trait_ref, ref self_type, ref impl_items) => {
1771 self.resolve_implementation(generics,
1778 ItemTrait(_, ref generics, ref bounds, ref trait_items) => {
1779 self.check_if_primitive_type_name(name, item.span);
1781 // Create a new rib for the trait-wide type parameters.
1782 self.with_type_parameter_rib(HasTypeParameters(generics,
1786 let local_def_id = this.ast_map.local_def_id(item.id);
1787 this.with_self_rib(Def::SelfTy(Some(local_def_id), None), |this| {
1788 this.visit_generics(generics);
1789 walk_list!(this, visit_ty_param_bound, bounds);
1791 for trait_item in trait_items {
1792 match trait_item.node {
1793 hir::ConstTraitItem(_, ref default) => {
1794 // Only impose the restrictions of
1795 // ConstRibKind if there's an actual constant
1796 // expression in a provided default.
1797 if default.is_some() {
1798 this.with_constant_rib(|this| {
1799 intravisit::walk_trait_item(this, trait_item)
1802 intravisit::walk_trait_item(this, trait_item)
1805 hir::MethodTraitItem(ref sig, _) => {
1806 let type_parameters =
1807 HasTypeParameters(&sig.generics,
1810 this.with_type_parameter_rib(type_parameters, |this| {
1811 intravisit::walk_trait_item(this, trait_item)
1814 hir::TypeTraitItem(..) => {
1815 this.check_if_primitive_type_name(trait_item.name,
1817 this.with_type_parameter_rib(NoTypeParameters, |this| {
1818 intravisit::walk_trait_item(this, trait_item)
1827 ItemMod(_) | ItemForeignMod(_) => {
1828 self.with_scope(Some(name), |this| {
1829 intravisit::walk_item(this, item);
1833 ItemConst(..) | ItemStatic(..) => {
1834 self.with_constant_rib(|this| {
1835 intravisit::walk_item(this, item);
1839 ItemUse(ref view_path) => {
1840 // check for imports shadowing primitive types
1841 let check_rename = |this: &Self, id, name| {
1842 match this.def_map.borrow().get(&id).map(|d| d.full_def()) {
1843 Some(Def::Enum(..)) | Some(Def::TyAlias(..)) | Some(Def::Struct(..)) |
1844 Some(Def::Trait(..)) | None => {
1845 this.check_if_primitive_type_name(name, item.span);
1851 match view_path.node {
1852 hir::ViewPathSimple(name, _) => {
1853 check_rename(self, item.id, name);
1855 hir::ViewPathList(ref prefix, ref items) => {
1857 if let Some(name) = item.node.rename() {
1858 check_rename(self, item.node.id(), name);
1862 // Resolve prefix of an import with empty braces (issue #28388)
1863 if items.is_empty() && !prefix.segments.is_empty() {
1864 match self.resolve_crate_relative_path(prefix.span,
1868 self.record_def(item.id, PathResolution::new(def, lp, 0)),
1872 ResolutionError::FailedToResolve(
1873 &path_names_to_string(prefix, 0)));
1874 self.record_def(item.id, err_path_resolution());
1883 ItemExternCrate(_) => {
1884 // do nothing, these are just around to be encoded
1889 fn with_type_parameter_rib<'b, F>(&'b mut self, type_parameters: TypeParameters<'a, 'b>, f: F)
1890 where F: FnOnce(&mut Resolver)
1892 match type_parameters {
1893 HasTypeParameters(generics, space, rib_kind) => {
1894 let mut function_type_rib = Rib::new(rib_kind);
1895 let mut seen_bindings = HashSet::new();
1896 for (index, type_parameter) in generics.ty_params.iter().enumerate() {
1897 let name = type_parameter.name;
1898 debug!("with_type_parameter_rib: {}", type_parameter.id);
1900 if seen_bindings.contains(&name) {
1902 type_parameter.span,
1903 ResolutionError::NameAlreadyUsedInTypeParameterList(name));
1905 seen_bindings.insert(name);
1907 // plain insert (no renaming)
1908 function_type_rib.bindings
1910 DlDef(Def::TyParam(space,
1913 .local_def_id(type_parameter.id),
1916 self.type_ribs.push(function_type_rib);
1919 NoTypeParameters => {
1926 match type_parameters {
1927 HasTypeParameters(..) => {
1929 self.type_ribs.pop();
1932 NoTypeParameters => {}
1936 fn with_label_rib<F>(&mut self, f: F)
1937 where F: FnOnce(&mut Resolver)
1939 self.label_ribs.push(Rib::new(NormalRibKind));
1942 self.label_ribs.pop();
1946 fn with_constant_rib<F>(&mut self, f: F)
1947 where F: FnOnce(&mut Resolver)
1949 self.value_ribs.push(Rib::new(ConstantItemRibKind));
1950 self.type_ribs.push(Rib::new(ConstantItemRibKind));
1953 self.type_ribs.pop();
1954 self.value_ribs.pop();
1958 fn resolve_function(&mut self, rib_kind: RibKind<'a>, declaration: &FnDecl, block: &Block) {
1959 // Create a value rib for the function.
1960 self.value_ribs.push(Rib::new(rib_kind));
1962 // Create a label rib for the function.
1963 self.label_ribs.push(Rib::new(rib_kind));
1965 // Add each argument to the rib.
1966 let mut bindings_list = HashMap::new();
1967 for argument in &declaration.inputs {
1968 self.resolve_pattern(&argument.pat, ArgumentIrrefutableMode, &mut bindings_list);
1970 self.visit_ty(&argument.ty);
1972 debug!("(resolving function) recorded argument");
1974 intravisit::walk_fn_ret_ty(self, &declaration.output);
1976 // Resolve the function body.
1977 self.visit_block(block);
1979 debug!("(resolving function) leaving function");
1982 self.label_ribs.pop();
1983 self.value_ribs.pop();
1987 fn resolve_trait_reference(&mut self,
1991 -> Result<PathResolution, ()> {
1992 if let Some(path_res) = self.resolve_path(id, trait_path, path_depth, TypeNS, true) {
1993 if let Def::Trait(_) = path_res.base_def {
1994 debug!("(resolving trait) found trait def: {:?}", path_res);
1998 resolve_struct_error(self,
2000 ResolutionError::IsNotATrait(&path_names_to_string(trait_path,
2003 // If it's a typedef, give a note
2004 if let Def::TyAlias(..) = path_res.base_def {
2005 err.span_note(trait_path.span,
2006 "`type` aliases cannot be used for traits");
2014 ResolutionError::UndeclaredTraitName(&path_names_to_string(trait_path,
2020 fn resolve_generics(&mut self, generics: &Generics) {
2021 for type_parameter in generics.ty_params.iter() {
2022 self.check_if_primitive_type_name(type_parameter.name, type_parameter.span);
2024 for predicate in &generics.where_clause.predicates {
2026 &hir::WherePredicate::BoundPredicate(_) |
2027 &hir::WherePredicate::RegionPredicate(_) => {}
2028 &hir::WherePredicate::EqPredicate(ref eq_pred) => {
2029 let path_res = self.resolve_path(eq_pred.id, &eq_pred.path, 0, TypeNS, true);
2030 if let Some(PathResolution { base_def: Def::TyParam(..), .. }) = path_res {
2031 self.record_def(eq_pred.id, path_res.unwrap());
2035 ResolutionError::UndeclaredAssociatedType);
2036 self.record_def(eq_pred.id, err_path_resolution());
2041 intravisit::walk_generics(self, generics);
2044 fn with_current_self_type<T, F>(&mut self, self_type: &Ty, f: F) -> T
2045 where F: FnOnce(&mut Resolver) -> T
2047 // Handle nested impls (inside fn bodies)
2048 let previous_value = replace(&mut self.current_self_type, Some(self_type.clone()));
2049 let result = f(self);
2050 self.current_self_type = previous_value;
2054 fn with_optional_trait_ref<T, F>(&mut self, opt_trait_ref: Option<&TraitRef>, f: F) -> T
2055 where F: FnOnce(&mut Resolver, Option<DefId>) -> T
2057 let mut new_val = None;
2058 let mut new_id = None;
2059 if let Some(trait_ref) = opt_trait_ref {
2060 if let Ok(path_res) = self.resolve_trait_reference(trait_ref.ref_id,
2063 assert!(path_res.depth == 0);
2064 self.record_def(trait_ref.ref_id, path_res);
2065 new_val = Some((path_res.base_def.def_id(), trait_ref.clone()));
2066 new_id = Some(path_res.base_def.def_id());
2068 self.record_def(trait_ref.ref_id, err_path_resolution());
2070 intravisit::walk_trait_ref(self, trait_ref);
2072 let original_trait_ref = replace(&mut self.current_trait_ref, new_val);
2073 let result = f(self, new_id);
2074 self.current_trait_ref = original_trait_ref;
2078 fn with_self_rib<F>(&mut self, self_def: Def, f: F)
2079 where F: FnOnce(&mut Resolver)
2081 let mut self_type_rib = Rib::new(NormalRibKind);
2083 // plain insert (no renaming, types are not currently hygienic....)
2084 let name = special_names::type_self;
2085 self_type_rib.bindings.insert(name, DlDef(self_def));
2086 self.type_ribs.push(self_type_rib);
2089 self.type_ribs.pop();
2093 fn resolve_implementation(&mut self,
2094 generics: &Generics,
2095 opt_trait_reference: &Option<TraitRef>,
2098 impl_items: &[ImplItem]) {
2099 // If applicable, create a rib for the type parameters.
2100 self.with_type_parameter_rib(HasTypeParameters(generics,
2104 // Resolve the type parameters.
2105 this.visit_generics(generics);
2107 // Resolve the trait reference, if necessary.
2108 this.with_optional_trait_ref(opt_trait_reference.as_ref(), |this, trait_id| {
2109 // Resolve the self type.
2110 this.visit_ty(self_type);
2112 this.with_self_rib(Def::SelfTy(trait_id, Some((item_id, self_type.id))), |this| {
2113 this.with_current_self_type(self_type, |this| {
2114 for impl_item in impl_items {
2115 match impl_item.node {
2116 hir::ImplItemKind::Const(..) => {
2117 // If this is a trait impl, ensure the const
2119 this.check_trait_item(impl_item.name,
2121 |n, s| ResolutionError::ConstNotMemberOfTrait(n, s));
2122 this.with_constant_rib(|this| {
2123 intravisit::walk_impl_item(this, impl_item);
2126 hir::ImplItemKind::Method(ref sig, _) => {
2127 // If this is a trait impl, ensure the method
2129 this.check_trait_item(impl_item.name,
2131 |n, s| ResolutionError::MethodNotMemberOfTrait(n, s));
2133 // We also need a new scope for the method-
2134 // specific type parameters.
2135 let type_parameters =
2136 HasTypeParameters(&sig.generics,
2139 this.with_type_parameter_rib(type_parameters, |this| {
2140 intravisit::walk_impl_item(this, impl_item);
2143 hir::ImplItemKind::Type(ref ty) => {
2144 // If this is a trait impl, ensure the type
2146 this.check_trait_item(impl_item.name,
2148 |n, s| ResolutionError::TypeNotMemberOfTrait(n, s));
2160 fn check_trait_item<F>(&self, name: Name, span: Span, err: F)
2161 where F: FnOnce(Name, &str) -> ResolutionError
2163 // If there is a TraitRef in scope for an impl, then the method must be in the
2165 if let Some((did, ref trait_ref)) = self.current_trait_ref {
2166 if !self.trait_item_map.contains_key(&(name, did)) {
2167 let path_str = path_names_to_string(&trait_ref.path, 0);
2168 resolve_error(self, span, err(name, &path_str));
2173 fn resolve_local(&mut self, local: &Local) {
2174 // Resolve the type.
2175 walk_list!(self, visit_ty, &local.ty);
2177 // Resolve the initializer.
2178 walk_list!(self, visit_expr, &local.init);
2180 // Resolve the pattern.
2181 self.resolve_pattern(&local.pat, LocalIrrefutableMode, &mut HashMap::new());
2184 // build a map from pattern identifiers to binding-info's.
2185 // this is done hygienically. This could arise for a macro
2186 // that expands into an or-pattern where one 'x' was from the
2187 // user and one 'x' came from the macro.
2188 fn binding_mode_map(&mut self, pat: &Pat) -> BindingMap {
2189 let mut result = HashMap::new();
2190 pat_bindings(&self.def_map, pat, |binding_mode, _id, sp, path1| {
2191 let name = path1.node;
2195 binding_mode: binding_mode,
2201 // check that all of the arms in an or-pattern have exactly the
2202 // same set of bindings, with the same binding modes for each.
2203 fn check_consistent_bindings(&mut self, arm: &Arm) {
2204 if arm.pats.is_empty() {
2207 let map_0 = self.binding_mode_map(&arm.pats[0]);
2208 for (i, p) in arm.pats.iter().enumerate() {
2209 let map_i = self.binding_mode_map(&p);
2211 for (&key, &binding_0) in &map_0 {
2212 match map_i.get(&key) {
2216 ResolutionError::VariableNotBoundInPattern(key, i + 1));
2218 Some(binding_i) => {
2219 if binding_0.binding_mode != binding_i.binding_mode {
2222 ResolutionError::VariableBoundWithDifferentMode(key,
2229 for (&key, &binding) in &map_i {
2230 if !map_0.contains_key(&key) {
2233 ResolutionError::VariableNotBoundInParentPattern(key, i + 1));
2239 fn resolve_arm(&mut self, arm: &Arm) {
2240 self.value_ribs.push(Rib::new(NormalRibKind));
2242 let mut bindings_list = HashMap::new();
2243 for pattern in &arm.pats {
2244 self.resolve_pattern(&pattern, RefutableMode, &mut bindings_list);
2247 // This has to happen *after* we determine which
2248 // pat_idents are variants
2249 self.check_consistent_bindings(arm);
2251 walk_list!(self, visit_expr, &arm.guard);
2252 self.visit_expr(&arm.body);
2255 self.value_ribs.pop();
2259 fn resolve_block(&mut self, block: &Block) {
2260 debug!("(resolving block) entering block");
2261 // Move down in the graph, if there's an anonymous module rooted here.
2262 let orig_module = self.current_module;
2263 let anonymous_module =
2264 orig_module.anonymous_children.borrow().get(&block.id).map(|module| *module);
2266 if let Some(anonymous_module) = anonymous_module {
2267 debug!("(resolving block) found anonymous module, moving down");
2268 self.value_ribs.push(Rib::new(AnonymousModuleRibKind(anonymous_module)));
2269 self.type_ribs.push(Rib::new(AnonymousModuleRibKind(anonymous_module)));
2270 self.current_module = anonymous_module;
2272 self.value_ribs.push(Rib::new(NormalRibKind));
2275 // Descend into the block.
2276 intravisit::walk_block(self, block);
2280 self.current_module = orig_module;
2281 self.value_ribs.pop();
2282 if let Some(_) = anonymous_module {
2283 self.type_ribs.pop();
2286 debug!("(resolving block) leaving block");
2289 fn resolve_type(&mut self, ty: &Ty) {
2291 TyPath(ref maybe_qself, ref path) => {
2292 let resolution = match self.resolve_possibly_assoc_item(ty.id,
2293 maybe_qself.as_ref(),
2297 // `<T>::a::b::c` is resolved by typeck alone.
2298 TypecheckRequired => {
2299 // Resolve embedded types.
2300 intravisit::walk_ty(self, ty);
2303 ResolveAttempt(resolution) => resolution,
2306 // This is a path in the type namespace. Walk through scopes
2310 // Write the result into the def map.
2311 debug!("(resolving type) writing resolution for `{}` (id {}) = {:?}",
2312 path_names_to_string(path, 0),
2315 self.record_def(ty.id, def);
2318 self.record_def(ty.id, err_path_resolution());
2320 // Keep reporting some errors even if they're ignored above.
2321 self.resolve_path(ty.id, path, 0, TypeNS, true);
2323 let kind = if maybe_qself.is_some() {
2329 let self_type_name = special_idents::type_self.name;
2330 let is_invalid_self_type_name = path.segments.len() > 0 &&
2331 maybe_qself.is_none() &&
2332 path.segments[0].identifier.name ==
2334 if is_invalid_self_type_name {
2337 ResolutionError::SelfUsedOutsideImplOrTrait);
2341 ResolutionError::UseOfUndeclared(
2343 &path_names_to_string(path,
2352 // Resolve embedded types.
2353 intravisit::walk_ty(self, ty);
2356 fn resolve_pattern(&mut self,
2358 mode: PatternBindingMode,
2359 // Maps idents to the node ID for the (outermost)
2360 // pattern that binds them
2361 bindings_list: &mut HashMap<Name, NodeId>) {
2362 let pat_id = pattern.id;
2363 walk_pat(pattern, |pattern| {
2364 match pattern.node {
2365 PatIdent(binding_mode, ref path1, ref at_rhs) => {
2366 // The meaning of PatIdent with no type parameters
2367 // depends on whether an enum variant or unit-like struct
2368 // with that name is in scope. The probing lookup has to
2369 // be careful not to emit spurious errors. Only matching
2370 // patterns (match) can match nullary variants or
2371 // unit-like structs. For binding patterns (let
2372 // and the LHS of @-patterns), matching such a value is
2373 // simply disallowed (since it's rarely what you want).
2374 let const_ok = mode == RefutableMode && at_rhs.is_none();
2376 let ident = path1.node;
2377 let renamed = ident.name;
2379 match self.resolve_bare_identifier_pattern(ident.unhygienic_name,
2381 FoundStructOrEnumVariant(def, lp) if const_ok => {
2382 debug!("(resolving pattern) resolving `{}` to struct or enum variant",
2385 self.enforce_default_binding_mode(pattern,
2388 self.record_def(pattern.id,
2395 FoundStructOrEnumVariant(..) => {
2399 ResolutionError::DeclarationShadowsEnumVariantOrUnitLikeStruct(
2402 self.record_def(pattern.id, err_path_resolution());
2404 FoundConst(def, lp, _) if const_ok => {
2405 debug!("(resolving pattern) resolving `{}` to constant", renamed);
2407 self.enforce_default_binding_mode(pattern, binding_mode, "a constant");
2408 self.record_def(pattern.id,
2415 FoundConst(def, _, name) => {
2419 ResolutionError::OnlyIrrefutablePatternsAllowedHere(def.def_id(),
2422 self.record_def(pattern.id, err_path_resolution());
2424 BareIdentifierPatternUnresolved => {
2425 debug!("(resolving pattern) binding `{}`", renamed);
2427 let def_id = self.ast_map.local_def_id(pattern.id);
2428 let def = Def::Local(def_id, pattern.id);
2430 // Record the definition so that later passes
2431 // will be able to distinguish variants from
2432 // locals in patterns.
2434 self.record_def(pattern.id,
2437 last_private: LastMod(AllPublic),
2441 // Add the binding to the local ribs, if it
2442 // doesn't already exist in the bindings list. (We
2443 // must not add it if it's in the bindings list
2444 // because that breaks the assumptions later
2445 // passes make about or-patterns.)
2446 if !bindings_list.contains_key(&renamed) {
2447 let this = &mut *self;
2448 let last_rib = this.value_ribs.last_mut().unwrap();
2449 last_rib.bindings.insert(renamed, DlDef(def));
2450 bindings_list.insert(renamed, pat_id);
2451 } else if mode == ArgumentIrrefutableMode &&
2452 bindings_list.contains_key(&renamed) {
2453 // Forbid duplicate bindings in the same
2458 ResolutionError::IdentifierBoundMoreThanOnceInParameterList(
2459 &ident.name.as_str())
2461 } else if bindings_list.get(&renamed) == Some(&pat_id) {
2462 // Then this is a duplicate variable in the
2463 // same disjunction, which is an error.
2467 ResolutionError::IdentifierBoundMoreThanOnceInSamePattern(
2468 &ident.name.as_str())
2471 // Else, not bound in the same pattern: do
2477 PatEnum(ref path, _) => {
2478 // This must be an enum variant, struct or const.
2479 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2484 // The below shouldn't happen because all
2485 // qualified paths should be in PatQPath.
2486 TypecheckRequired =>
2487 self.session.span_bug(path.span,
2488 "resolve_possibly_assoc_item claimed
2490 that a path in PatEnum requires typecheck
2492 to resolve, but qualified paths should be
2495 ResolveAttempt(resolution) => resolution,
2497 if let Some(path_res) = resolution {
2498 match path_res.base_def {
2499 Def::Struct(..) if path_res.depth == 0 => {
2500 self.record_def(pattern.id, path_res);
2502 Def::Variant(..) | Def::Const(..) => {
2503 self.record_def(pattern.id, path_res);
2505 Def::Static(..) => {
2506 resolve_error(&self,
2508 ResolutionError::StaticVariableReference);
2509 self.record_def(pattern.id, err_path_resolution());
2512 // If anything ends up here entirely resolved,
2513 // it's an error. If anything ends up here
2514 // partially resolved, that's OK, because it may
2515 // be a `T::CONST` that typeck will resolve.
2516 if path_res.depth == 0 {
2520 ResolutionError::NotAnEnumVariantStructOrConst(
2528 self.record_def(pattern.id, err_path_resolution());
2530 let const_name = path.segments
2535 let traits = self.get_traits_containing_item(const_name);
2536 self.trait_map.insert(pattern.id, traits);
2537 self.record_def(pattern.id, path_res);
2545 ResolutionError::UnresolvedEnumVariantStructOrConst(
2546 &path.segments.last().unwrap().identifier.name.as_str())
2548 self.record_def(pattern.id, err_path_resolution());
2550 intravisit::walk_path(self, path);
2553 PatQPath(ref qself, ref path) => {
2554 // Associated constants only.
2555 let resolution = match self.resolve_possibly_assoc_item(pat_id,
2560 TypecheckRequired => {
2561 // All `<T>::CONST` should end up here, and will
2562 // require use of the trait map to resolve
2563 // during typechecking.
2564 let const_name = path.segments
2569 let traits = self.get_traits_containing_item(const_name);
2570 self.trait_map.insert(pattern.id, traits);
2571 intravisit::walk_pat(self, pattern);
2574 ResolveAttempt(resolution) => resolution,
2576 if let Some(path_res) = resolution {
2577 match path_res.base_def {
2578 // All `<T as Trait>::CONST` should end up here, and
2579 // have the trait already selected.
2580 Def::AssociatedConst(..) => {
2581 self.record_def(pattern.id, path_res);
2587 ResolutionError::NotAnAssociatedConst(
2588 &path.segments.last().unwrap().identifier.name.as_str()
2591 self.record_def(pattern.id, err_path_resolution());
2597 ResolutionError::UnresolvedAssociatedConst(&path.segments
2603 self.record_def(pattern.id, err_path_resolution());
2605 intravisit::walk_pat(self, pattern);
2608 PatStruct(ref path, _, _) => {
2609 match self.resolve_path(pat_id, path, 0, TypeNS, false) {
2610 Some(definition) => {
2611 self.record_def(pattern.id, definition);
2614 debug!("(resolving pattern) didn't find struct def: {:?}", result);
2618 ResolutionError::DoesNotNameAStruct(
2619 &path_names_to_string(path, 0))
2621 self.record_def(pattern.id, err_path_resolution());
2624 intravisit::walk_path(self, path);
2627 PatLit(_) | PatRange(..) => {
2628 intravisit::walk_pat(self, pattern);
2639 fn resolve_bare_identifier_pattern(&mut self,
2642 -> BareIdentifierPatternResolution {
2643 let module = self.current_module;
2644 match self.resolve_item_in_lexical_scope(module, name, ValueNS, true) {
2645 Success(binding) => {
2646 debug!("(resolve bare identifier pattern) succeeded in finding {} at {:?}",
2649 match binding.def() {
2651 panic!("resolved name in the value namespace to a set of name bindings \
2654 // For the two success cases, this lookup can be
2655 // considered as not having a private component because
2656 // the lookup happened only within the current module.
2657 Some(def @ Def::Variant(..)) | Some(def @ Def::Struct(..)) => {
2658 return FoundStructOrEnumVariant(def, LastMod(AllPublic));
2660 Some(def @ Def::Const(..)) | Some(def @ Def::AssociatedConst(..)) => {
2661 return FoundConst(def, LastMod(AllPublic), name);
2663 Some(Def::Static(..)) => {
2664 resolve_error(self, span, ResolutionError::StaticVariableReference);
2665 return BareIdentifierPatternUnresolved;
2667 _ => return BareIdentifierPatternUnresolved
2671 Indeterminate => return BareIdentifierPatternUnresolved,
2674 Some((span, msg)) => {
2675 resolve_error(self, span, ResolutionError::FailedToResolve(&msg));
2680 debug!("(resolve bare identifier pattern) failed to find {}", name);
2681 return BareIdentifierPatternUnresolved;
2686 /// Handles paths that may refer to associated items
2687 fn resolve_possibly_assoc_item(&mut self,
2689 maybe_qself: Option<&hir::QSelf>,
2691 namespace: Namespace,
2693 -> AssocItemResolveResult {
2694 let max_assoc_types;
2698 if qself.position == 0 {
2699 return TypecheckRequired;
2701 max_assoc_types = path.segments.len() - qself.position;
2702 // Make sure the trait is valid.
2703 let _ = self.resolve_trait_reference(id, path, max_assoc_types);
2706 max_assoc_types = path.segments.len();
2710 let mut resolution = self.with_no_errors(|this| {
2711 this.resolve_path(id, path, 0, namespace, check_ribs)
2713 for depth in 1..max_assoc_types {
2714 if resolution.is_some() {
2717 self.with_no_errors(|this| {
2718 resolution = this.resolve_path(id, path, depth, TypeNS, true);
2721 if let Some(Def::Mod(_)) = resolution.map(|r| r.base_def) {
2722 // A module is not a valid type or value.
2725 ResolveAttempt(resolution)
2728 /// If `check_ribs` is true, checks the local definitions first; i.e.
2729 /// doesn't skip straight to the containing module.
2730 /// Skips `path_depth` trailing segments, which is also reflected in the
2731 /// returned value. See `middle::def::PathResolution` for more info.
2732 pub fn resolve_path(&mut self,
2736 namespace: Namespace,
2738 -> Option<PathResolution> {
2739 let span = path.span;
2740 let segments = &path.segments[..path.segments.len() - path_depth];
2742 let mk_res = |(def, lp)| PathResolution::new(def, lp, path_depth);
2745 let def = self.resolve_crate_relative_path(span, segments, namespace);
2746 return def.map(mk_res);
2749 // Try to find a path to an item in a module.
2750 let last_ident = segments.last().unwrap().identifier;
2751 if segments.len() <= 1 {
2752 let unqualified_def = self.resolve_identifier(last_ident, namespace, check_ribs, true);
2753 return unqualified_def.and_then(|def| self.adjust_local_def(def, span))
2755 PathResolution::new(def, LastMod(AllPublic), path_depth)
2759 let unqualified_def = self.resolve_identifier(last_ident, namespace, check_ribs, false);
2760 let def = self.resolve_module_relative_path(span, segments, namespace);
2761 match (def, unqualified_def) {
2762 (Some((ref d, _)), Some(ref ud)) if *d == ud.def => {
2764 .add_lint(lint::builtin::UNUSED_QUALIFICATIONS,
2767 "unnecessary qualification".to_string());
2775 // Resolve a single identifier
2776 fn resolve_identifier(&mut self,
2777 identifier: hir::Ident,
2778 namespace: Namespace,
2781 -> Option<LocalDef> {
2782 if identifier.name == special_idents::invalid.name {
2783 return Some(LocalDef::from_def(Def::Err));
2786 // First, check to see whether the name is a primitive type.
2787 if namespace == TypeNS {
2788 if let Some(&prim_ty) = self.primitive_type_table
2790 .get(&identifier.unhygienic_name) {
2791 return Some(LocalDef::from_def(Def::PrimTy(prim_ty)));
2796 if let Some(def) = self.resolve_identifier_in_local_ribs(identifier, namespace) {
2802 let module = self.current_module;
2803 let name = identifier.unhygienic_name;
2804 match self.resolve_item_in_lexical_scope(module, name, namespace, record_used) {
2805 Success(binding) => binding.def().map(LocalDef::from_def),
2806 Failed(Some((span, msg))) => {
2807 resolve_error(self, span, ResolutionError::FailedToResolve(&msg));
2814 // Resolve a local definition, potentially adjusting for closures.
2815 fn adjust_local_def(&mut self, local_def: LocalDef, span: Span) -> Option<Def> {
2816 let ribs = match local_def.ribs {
2817 Some((TypeNS, i)) => &self.type_ribs[i + 1..],
2818 Some((ValueNS, i)) => &self.value_ribs[i + 1..],
2821 let mut def = local_def.def;
2824 self.session.span_bug(span, &format!("unexpected {:?} in bindings", def))
2826 Def::Local(_, node_id) => {
2829 NormalRibKind | AnonymousModuleRibKind(..) => {
2830 // Nothing to do. Continue.
2832 ClosureRibKind(function_id) => {
2834 let node_def_id = self.ast_map.local_def_id(node_id);
2836 let seen = self.freevars_seen
2838 .or_insert_with(|| NodeMap());
2839 if let Some(&index) = seen.get(&node_id) {
2840 def = Def::Upvar(node_def_id, node_id, index, function_id);
2843 let vec = self.freevars
2845 .or_insert_with(|| vec![]);
2846 let depth = vec.len();
2852 def = Def::Upvar(node_def_id, node_id, depth, function_id);
2853 seen.insert(node_id, depth);
2855 ItemRibKind | MethodRibKind => {
2856 // This was an attempt to access an upvar inside a
2857 // named function item. This is not allowed, so we
2861 ResolutionError::CannotCaptureDynamicEnvironmentInFnItem);
2864 ConstantItemRibKind => {
2865 // Still doesn't deal with upvars
2868 ResolutionError::AttemptToUseNonConstantValueInConstant);
2874 Def::TyParam(..) | Def::SelfTy(..) => {
2877 NormalRibKind | MethodRibKind | ClosureRibKind(..) |
2878 AnonymousModuleRibKind(..) => {
2879 // Nothing to do. Continue.
2882 // This was an attempt to use a type parameter outside
2887 ResolutionError::TypeParametersFromOuterFunction);
2890 ConstantItemRibKind => {
2892 resolve_error(self, span, ResolutionError::OuterTypeParameterContext);
2903 // resolve a "module-relative" path, e.g. a::b::c
2904 fn resolve_module_relative_path(&mut self,
2906 segments: &[hir::PathSegment],
2907 namespace: Namespace)
2908 -> Option<(Def, LastPrivate)> {
2909 let module_path = segments.split_last()
2913 .map(|ps| ps.identifier.name)
2914 .collect::<Vec<_>>();
2916 let containing_module;
2918 let current_module = self.current_module;
2919 match self.resolve_module_path(current_module, &module_path, UseLexicalScope, span) {
2921 let (span, msg) = match err {
2922 Some((span, msg)) => (span, msg),
2924 let msg = format!("Use of undeclared type or module `{}`",
2925 names_to_string(&module_path));
2930 resolve_error(self, span, ResolutionError::FailedToResolve(&msg));
2933 Indeterminate => return None,
2934 Success((resulting_module, resulting_last_private)) => {
2935 containing_module = resulting_module;
2936 last_private = resulting_last_private;
2940 let name = segments.last().unwrap().identifier.name;
2941 let result = self.resolve_name_in_module(containing_module, name, namespace, false, true);
2942 let def = match result {
2943 Success(binding) => {
2944 let (def, lp) = binding.def_and_lp();
2945 (def, last_private.or(lp))
2952 /// Invariant: This must be called only during main resolution, not during
2953 /// import resolution.
2954 fn resolve_crate_relative_path(&mut self,
2956 segments: &[hir::PathSegment],
2957 namespace: Namespace)
2958 -> Option<(Def, LastPrivate)> {
2959 let module_path = segments.split_last()
2963 .map(|ps| ps.identifier.name)
2964 .collect::<Vec<_>>();
2966 let root_module = self.graph_root;
2968 let containing_module;
2970 match self.resolve_module_path_from_root(root_module,
2974 LastMod(AllPublic)) {
2976 let (span, msg) = match err {
2977 Some((span, msg)) => (span, msg),
2979 let msg = format!("Use of undeclared module `::{}`",
2980 names_to_string(&module_path));
2985 resolve_error(self, span, ResolutionError::FailedToResolve(&msg));
2989 Indeterminate => return None,
2991 Success((resulting_module, resulting_last_private)) => {
2992 containing_module = resulting_module;
2993 last_private = resulting_last_private;
2997 let name = segments.last().unwrap().identifier.name;
2998 match self.resolve_name_in_module(containing_module, name, namespace, false, true) {
2999 Success(binding) => {
3000 let (def, lp) = binding.def_and_lp();
3001 Some((def, last_private.or(lp)))
3007 fn resolve_identifier_in_local_ribs(&mut self,
3009 namespace: Namespace)
3010 -> Option<LocalDef> {
3011 // Check the local set of ribs.
3012 let name = match namespace { ValueNS => ident.name, TypeNS => ident.unhygienic_name };
3014 for i in (0 .. self.get_ribs(namespace).len()).rev() {
3015 if let Some(def_like) = self.get_ribs(namespace)[i].bindings.get(&name).cloned() {
3018 debug!("(resolving path in local ribs) resolved `{}` to {:?} at {}",
3022 return Some(LocalDef {
3023 ribs: Some((namespace, i)),
3028 debug!("(resolving path in local ribs) resolved `{}` to pseudo-def {:?}",
3036 if let AnonymousModuleRibKind(module) = self.get_ribs(namespace)[i].kind {
3037 if let Success(binding) = self.resolve_name_in_module(module,
3038 ident.unhygienic_name,
3042 if let Some(def) = binding.def() {
3043 return Some(LocalDef::from_def(def));
3052 fn with_no_errors<T, F>(&mut self, f: F) -> T
3053 where F: FnOnce(&mut Resolver) -> T
3055 self.emit_errors = false;
3057 self.emit_errors = true;
3061 fn find_fallback_in_self_type(&mut self, name: Name) -> FallbackSuggestion {
3062 fn extract_path_and_node_id(t: &Ty,
3063 allow: FallbackChecks)
3064 -> Option<(Path, NodeId, FallbackChecks)> {
3066 TyPath(None, ref path) => Some((path.clone(), t.id, allow)),
3067 TyPtr(ref mut_ty) => extract_path_and_node_id(&mut_ty.ty, OnlyTraitAndStatics),
3068 TyRptr(_, ref mut_ty) => extract_path_and_node_id(&mut_ty.ty, allow),
3069 // This doesn't handle the remaining `Ty` variants as they are not
3070 // that commonly the self_type, it might be interesting to provide
3071 // support for those in future.
3076 fn get_module<'a, 'tcx>(this: &mut Resolver<'a, 'tcx>,
3078 name_path: &[ast::Name])
3079 -> Option<Module<'a>> {
3080 let root = this.current_module;
3081 let last_name = name_path.last().unwrap();
3083 if name_path.len() == 1 {
3084 match this.primitive_type_table.primitive_types.get(last_name) {
3086 None => this.current_module.resolve_name(*last_name, TypeNS, true).success()
3087 .and_then(NameBinding::module)
3090 match this.resolve_module_path(root, &name_path, UseLexicalScope, span) {
3091 Success((module, _)) => Some(module),
3097 fn is_static_method(this: &Resolver, did: DefId) -> bool {
3098 if let Some(node_id) = this.ast_map.as_local_node_id(did) {
3099 let sig = match this.ast_map.get(node_id) {
3100 hir_map::NodeTraitItem(trait_item) => match trait_item.node {
3101 hir::MethodTraitItem(ref sig, _) => sig,
3104 hir_map::NodeImplItem(impl_item) => match impl_item.node {
3105 hir::ImplItemKind::Method(ref sig, _) => sig,
3110 sig.explicit_self.node == hir::SelfStatic
3112 this.session.cstore.is_static_method(did)
3116 let (path, node_id, allowed) = match self.current_self_type {
3117 Some(ref ty) => match extract_path_and_node_id(ty, Everything) {
3119 None => return NoSuggestion,
3121 None => return NoSuggestion,
3124 if allowed == Everything {
3125 // Look for a field with the same name in the current self_type.
3126 match self.def_map.borrow().get(&node_id).map(|d| d.full_def()) {
3127 Some(Def::Enum(did)) |
3128 Some(Def::TyAlias(did)) |
3129 Some(Def::Struct(did)) |
3130 Some(Def::Variant(_, did)) => match self.structs.get(&did) {
3133 if fields.iter().any(|&field_name| name == field_name) {
3138 _ => {} // Self type didn't resolve properly
3142 let name_path = path.segments.iter().map(|seg| seg.identifier.name).collect::<Vec<_>>();
3144 // Look for a method in the current self type's impl module.
3145 if let Some(module) = get_module(self, path.span, &name_path) {
3146 if let Success(binding) = module.resolve_name(name, ValueNS, true) {
3147 if let Some(Def::Method(did)) = binding.def() {
3148 if is_static_method(self, did) {
3149 return StaticMethod(path_names_to_string(&path, 0));
3151 if self.current_trait_ref.is_some() {
3153 } else if allowed == Everything {
3160 // Look for a method in the current trait.
3161 if let Some((trait_did, ref trait_ref)) = self.current_trait_ref {
3162 if let Some(&did) = self.trait_item_map.get(&(name, trait_did)) {
3163 if is_static_method(self, did) {
3164 return TraitMethod(path_names_to_string(&trait_ref.path, 0));
3174 fn find_best_match(&mut self, name: &str) -> SuggestionType {
3175 if let Some(macro_name) = self.session.available_macros
3176 .borrow().iter().find(|n| n.as_str() == name) {
3177 return SuggestionType::Macro(format!("{}!", macro_name));
3180 let names = self.value_ribs
3183 .flat_map(|rib| rib.bindings.keys());
3185 if let Some(found) = find_best_match_for_name(names, name, None) {
3187 return SuggestionType::Function(found);
3189 } SuggestionType::NotFound
3192 fn resolve_expr(&mut self, expr: &Expr) {
3193 // First, record candidate traits for this expression if it could
3194 // result in the invocation of a method call.
3196 self.record_candidate_traits_for_expr_if_necessary(expr);
3198 // Next, resolve the node.
3200 ExprPath(ref maybe_qself, ref path) => {
3201 let resolution = match self.resolve_possibly_assoc_item(expr.id,
3202 maybe_qself.as_ref(),
3206 // `<T>::a::b::c` is resolved by typeck alone.
3207 TypecheckRequired => {
3208 let method_name = path.segments.last().unwrap().identifier.name;
3209 let traits = self.get_traits_containing_item(method_name);
3210 self.trait_map.insert(expr.id, traits);
3211 intravisit::walk_expr(self, expr);
3214 ResolveAttempt(resolution) => resolution,
3217 // This is a local path in the value namespace. Walk through
3218 // scopes looking for it.
3219 if let Some(path_res) = resolution {
3220 // Check if struct variant
3221 let is_struct_variant = if let Def::Variant(_, variant_id) = path_res.base_def {
3222 self.structs.contains_key(&variant_id)
3226 if is_struct_variant {
3227 let _ = self.structs.contains_key(&path_res.base_def.def_id());
3228 let path_name = path_names_to_string(path, 0);
3230 let mut err = resolve_struct_error(self,
3232 ResolutionError::StructVariantUsedAsFunction(&path_name));
3234 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3236 if self.emit_errors {
3237 err.fileline_help(expr.span, &msg);
3239 err.span_help(expr.span, &msg);
3242 self.record_def(expr.id, err_path_resolution());
3244 // Write the result into the def map.
3245 debug!("(resolving expr) resolved `{}`",
3246 path_names_to_string(path, 0));
3248 // Partial resolutions will need the set of traits in scope,
3249 // so they can be completed during typeck.
3250 if path_res.depth != 0 {
3251 let method_name = path.segments.last().unwrap().identifier.name;
3252 let traits = self.get_traits_containing_item(method_name);
3253 self.trait_map.insert(expr.id, traits);
3256 self.record_def(expr.id, path_res);
3259 // Be helpful if the name refers to a struct
3260 // (The pattern matching def_tys where the id is in self.structs
3261 // matches on regular structs while excluding tuple- and enum-like
3262 // structs, which wouldn't result in this error.)
3263 let path_name = path_names_to_string(path, 0);
3264 let type_res = self.with_no_errors(|this| {
3265 this.resolve_path(expr.id, path, 0, TypeNS, false)
3268 self.record_def(expr.id, err_path_resolution());
3269 match type_res.map(|r| r.base_def) {
3270 Some(Def::Struct(..)) => {
3271 let mut err = resolve_struct_error(self,
3273 ResolutionError::StructVariantUsedAsFunction(&path_name));
3275 let msg = format!("did you mean to write: `{} {{ /* fields */ }}`?",
3277 if self.emit_errors {
3278 err.fileline_help(expr.span, &msg);
3280 err.span_help(expr.span, &msg);
3285 // Keep reporting some errors even if they're ignored above.
3286 self.resolve_path(expr.id, path, 0, ValueNS, true);
3288 let mut method_scope = false;
3289 self.value_ribs.iter().rev().all(|rib| {
3290 method_scope = match rib.kind {
3291 MethodRibKind => true,
3292 ItemRibKind | ConstantItemRibKind => false,
3293 _ => return true, // Keep advancing
3295 false // Stop advancing
3298 if method_scope && special_names::self_.as_str() == &path_name[..] {
3301 ResolutionError::SelfNotAvailableInStaticMethod);
3303 let last_name = path.segments.last().unwrap().identifier.name;
3304 let mut msg = match self.find_fallback_in_self_type(last_name) {
3306 // limit search to 5 to reduce the number
3307 // of stupid suggestions
3308 match self.find_best_match(&path_name) {
3309 SuggestionType::Macro(s) => {
3310 format!("the macro `{}`", s)
3312 SuggestionType::Function(s) => format!("`{}`", s),
3313 SuggestionType::NotFound => "".to_string(),
3316 Field => format!("`self.{}`", path_name),
3318 TraitItem => format!("to call `self.{}`", path_name),
3319 TraitMethod(path_str) |
3320 StaticMethod(path_str) =>
3321 format!("to call `{}::{}`", path_str, path_name),
3324 let mut context = UnresolvedNameContext::Other;
3325 if !msg.is_empty() {
3326 msg = format!(". Did you mean {}?", msg);
3328 // we check if this a module and if so, we display a help
3330 let name_path = path.segments.iter()
3331 .map(|seg| seg.identifier.name)
3332 .collect::<Vec<_>>();
3333 let current_module = self.current_module;
3335 match self.resolve_module_path(current_module,
3340 context = UnresolvedNameContext::PathIsMod(expr.id);
3348 ResolutionError::UnresolvedName(
3349 &path_name, &msg, context));
3355 intravisit::walk_expr(self, expr);
3358 ExprStruct(ref path, _, _) => {
3359 // Resolve the path to the structure it goes to. We don't
3360 // check to ensure that the path is actually a structure; that
3361 // is checked later during typeck.
3362 match self.resolve_path(expr.id, path, 0, TypeNS, false) {
3363 Some(definition) => self.record_def(expr.id, definition),
3365 debug!("(resolving expression) didn't find struct def",);
3369 ResolutionError::DoesNotNameAStruct(
3370 &path_names_to_string(path, 0))
3372 self.record_def(expr.id, err_path_resolution());
3376 intravisit::walk_expr(self, expr);
3379 ExprLoop(_, Some(label)) | ExprWhile(_, _, Some(label)) => {
3380 self.with_label_rib(|this| {
3381 let def_like = DlDef(Def::Label(expr.id));
3384 let rib = this.label_ribs.last_mut().unwrap();
3385 rib.bindings.insert(label.name, def_like);
3388 intravisit::walk_expr(this, expr);
3392 ExprBreak(Some(label)) | ExprAgain(Some(label)) => {
3393 match self.search_label(label.node.name) {
3395 self.record_def(expr.id, err_path_resolution());
3398 ResolutionError::UndeclaredLabel(&label.node.name.as_str()))
3400 Some(DlDef(def @ Def::Label(_))) => {
3401 // Since this def is a label, it is never read.
3402 self.record_def(expr.id,
3405 last_private: LastMod(AllPublic),
3410 self.session.span_bug(expr.span, "label wasn't mapped to a label def!")
3416 intravisit::walk_expr(self, expr);
3421 fn record_candidate_traits_for_expr_if_necessary(&mut self, expr: &Expr) {
3423 ExprField(_, name) => {
3424 // FIXME(#6890): Even though you can't treat a method like a
3425 // field, we need to add any trait methods we find that match
3426 // the field name so that we can do some nice error reporting
3427 // later on in typeck.
3428 let traits = self.get_traits_containing_item(name.node);
3429 self.trait_map.insert(expr.id, traits);
3431 ExprMethodCall(name, _, _) => {
3432 debug!("(recording candidate traits for expr) recording traits for {}",
3434 let traits = self.get_traits_containing_item(name.node);
3435 self.trait_map.insert(expr.id, traits);
3443 fn get_traits_containing_item(&mut self, name: Name) -> Vec<DefId> {
3444 debug!("(getting traits containing item) looking for '{}'", name);
3446 fn add_trait_info(found_traits: &mut Vec<DefId>, trait_def_id: DefId, name: Name) {
3447 debug!("(adding trait info) found trait {:?} for method '{}'",
3450 found_traits.push(trait_def_id);
3453 let mut found_traits = Vec::new();
3454 let mut search_module = self.current_module;
3456 // Look for the current trait.
3457 match self.current_trait_ref {
3458 Some((trait_def_id, _)) => {
3459 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3460 add_trait_info(&mut found_traits, trait_def_id, name);
3463 None => {} // Nothing to do.
3466 // Look for trait children.
3467 build_reduced_graph::populate_module_if_necessary(self, &search_module);
3469 search_module.for_each_child(|_, ns, name_binding| {
3470 if ns != TypeNS { return }
3471 let trait_def_id = match name_binding.def() {
3472 Some(Def::Trait(trait_def_id)) => trait_def_id,
3473 Some(..) | None => return,
3475 if self.trait_item_map.contains_key(&(name, trait_def_id)) {
3476 add_trait_info(&mut found_traits, trait_def_id, name);
3477 let trait_name = self.get_trait_name(trait_def_id);
3478 self.record_use(trait_name, TypeNS, name_binding);
3482 // Look for shadowed traits.
3483 for binding in search_module.shadowed_traits.borrow().iter() {
3484 let did = binding.def().unwrap().def_id();
3485 if self.trait_item_map.contains_key(&(name, did)) {
3486 add_trait_info(&mut found_traits, did, name);
3487 let trait_name = self.get_trait_name(did);
3488 self.record_use(trait_name, TypeNS, binding);
3492 match search_module.parent_link {
3493 NoParentLink | ModuleParentLink(..) => break,
3494 BlockParentLink(parent_module, _) => {
3495 search_module = parent_module;
3503 fn record_def(&mut self, node_id: NodeId, resolution: PathResolution) {
3504 debug!("(recording def) recording {:?} for {}", resolution, node_id);
3505 assert!(match resolution.last_private {
3506 LastImport{..} => false,
3509 "Import should only be used for `use` directives");
3511 if let Some(prev_res) = self.def_map.borrow_mut().insert(node_id, resolution) {
3512 let span = self.ast_map.opt_span(node_id).unwrap_or(codemap::DUMMY_SP);
3513 self.session.span_bug(span,
3514 &format!("path resolved multiple times ({:?} before, {:?} now)",
3520 fn enforce_default_binding_mode(&mut self,
3522 pat_binding_mode: BindingMode,
3524 match pat_binding_mode {
3525 BindByValue(_) => {}
3529 ResolutionError::CannotUseRefBindingModeWith(descr));
3536 fn names_to_string(names: &[Name]) -> String {
3537 let mut first = true;
3538 let mut result = String::new();
3543 result.push_str("::")
3545 result.push_str(&name.as_str());
3550 fn path_names_to_string(path: &Path, depth: usize) -> String {
3551 let names: Vec<ast::Name> = path.segments[..path.segments.len() - depth]
3553 .map(|seg| seg.identifier.name)
3555 names_to_string(&names[..])
3558 /// A somewhat inefficient routine to obtain the name of a module.
3559 fn module_to_string<'a>(module: Module<'a>) -> String {
3560 let mut names = Vec::new();
3562 fn collect_mod<'a>(names: &mut Vec<ast::Name>, module: Module<'a>) {
3563 match module.parent_link {
3565 ModuleParentLink(ref module, name) => {
3567 collect_mod(names, module);
3569 BlockParentLink(ref module, _) => {
3570 // danger, shouldn't be ident?
3571 names.push(special_idents::opaque.name);
3572 collect_mod(names, module);
3576 collect_mod(&mut names, module);
3578 if names.is_empty() {
3579 return "???".to_string();
3581 names_to_string(&names.into_iter().rev().collect::<Vec<ast::Name>>())
3584 fn err_path_resolution() -> PathResolution {
3587 last_private: LastMod(AllPublic),
3593 pub struct CrateMap {
3594 pub def_map: RefCell<DefMap>,
3595 pub freevars: FreevarMap,
3596 pub export_map: ExportMap,
3597 pub trait_map: TraitMap,
3598 pub external_exports: ExternalExports,
3599 pub glob_map: Option<GlobMap>,
3602 #[derive(PartialEq,Copy, Clone)]
3603 pub enum MakeGlobMap {
3608 /// Entry point to crate resolution.
3609 pub fn resolve_crate<'a, 'tcx>(session: &'a Session,
3610 ast_map: &'a hir_map::Map<'tcx>,
3611 make_glob_map: MakeGlobMap)
3613 // Currently, we ignore the name resolution data structures for
3614 // the purposes of dependency tracking. Instead we will run name
3615 // resolution and include its output in the hash of each item,
3616 // much like we do for macro expansion. In other words, the hash
3617 // reflects not just its contents but the results of name
3618 // resolution on those contents. Hopefully we'll push this back at
3620 let _task = ast_map.dep_graph.in_task(DepNode::Resolve);
3622 let krate = ast_map.krate();
3623 let arenas = Resolver::arenas();
3624 let mut resolver = create_resolver(session, ast_map, krate, make_glob_map, &arenas, None);
3626 resolver.resolve_crate(krate);
3628 check_unused::check_crate(&mut resolver, krate);
3631 def_map: resolver.def_map,
3632 freevars: resolver.freevars,
3633 export_map: resolver.export_map,
3634 trait_map: resolver.trait_map,
3635 external_exports: resolver.external_exports,
3636 glob_map: if resolver.make_glob_map {
3637 Some(resolver.glob_map)
3644 /// Builds a name resolution walker to be used within this module,
3645 /// or used externally, with an optional callback function.
3647 /// The callback takes a &mut bool which allows callbacks to end a
3648 /// walk when set to true, passing through the rest of the walk, while
3649 /// preserving the ribs + current module. This allows resolve_path
3650 /// calls to be made with the correct scope info. The node in the
3651 /// callback corresponds to the current node in the walk.
3652 pub fn create_resolver<'a, 'tcx>(session: &'a Session,
3653 ast_map: &'a hir_map::Map<'tcx>,
3655 make_glob_map: MakeGlobMap,
3656 arenas: &'a ResolverArenas<'a>,
3657 callback: Option<Box<Fn(hir_map::Node, &mut bool) -> bool>>)
3658 -> Resolver<'a, 'tcx> {
3659 let mut resolver = Resolver::new(session, ast_map, make_glob_map, arenas);
3661 resolver.callback = callback;
3663 build_reduced_graph::build_reduced_graph(&mut resolver, krate);
3665 resolve_imports::resolve_imports(&mut resolver);
3670 __build_diagnostic_array! { librustc_resolve, DIAGNOSTICS }