1 // Copyright 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 use self::ImportDirectiveSubclass::*;
13 use {AmbiguityError, Module, PerNS};
14 use Namespace::{self, TypeNS, MacroNS};
15 use {NameBinding, NameBindingKind, PathResult, PrivacyError};
17 use {names_to_string, module_to_string};
18 use {resolve_error, ResolutionError};
21 use rustc::lint::builtin::PRIVATE_IN_PUBLIC;
22 use rustc::hir::def_id::DefId;
23 use rustc::hir::def::*;
24 use rustc::util::nodemap::FxHashMap;
26 use syntax::ast::{Ident, NodeId};
27 use syntax::ext::base::Determinacy::{self, Determined, Undetermined};
28 use syntax::ext::hygiene::Mark;
29 use syntax::parse::token;
30 use syntax::symbol::keywords;
31 use syntax::util::lev_distance::find_best_match_for_name;
34 use std::cell::{Cell, RefCell};
37 /// Contains data for specific types of import directives.
38 #[derive(Clone, Debug)]
39 pub enum ImportDirectiveSubclass<'a> {
43 result: PerNS<Cell<Result<&'a NameBinding<'a>, Determinacy>>>,
48 max_vis: Cell<ty::Visibility>, // The visibility of the greatest reexport.
49 // n.b. `max_vis` is only used in `finalize_import` to check for reexport errors.
55 /// One import directive.
56 #[derive(Debug,Clone)]
57 pub struct ImportDirective<'a> {
59 pub parent: Module<'a>,
60 pub module_path: Vec<Ident>,
61 pub imported_module: Cell<Option<Module<'a>>>, // the resolution of `module_path`
62 pub subclass: ImportDirectiveSubclass<'a>,
64 pub vis: Cell<ty::Visibility>,
69 impl<'a> ImportDirective<'a> {
70 pub fn is_glob(&self) -> bool {
71 match self.subclass { ImportDirectiveSubclass::GlobImport { .. } => true, _ => false }
75 #[derive(Clone, Default)]
76 /// Records information about the resolution of a name in a namespace of a module.
77 pub struct NameResolution<'a> {
78 /// The single imports that define the name in the namespace.
79 single_imports: SingleImports<'a>,
80 /// The least shadowable known binding for this name, or None if there are no known bindings.
81 pub binding: Option<&'a NameBinding<'a>>,
82 shadows_glob: Option<&'a NameBinding<'a>>,
85 #[derive(Clone, Debug)]
86 enum SingleImports<'a> {
87 /// No single imports can define the name in the namespace.
89 /// Only the given single import can define the name in the namespace.
90 MaybeOne(&'a ImportDirective<'a>),
91 /// At least one single import will define the name in the namespace.
95 impl<'a> Default for SingleImports<'a> {
96 /// Creates a `SingleImports<'a>` of None type.
97 fn default() -> Self {
102 impl<'a> SingleImports<'a> {
103 fn add_directive(&mut self, directive: &'a ImportDirective<'a>) {
105 SingleImports::None => *self = SingleImports::MaybeOne(directive),
106 // If two single imports can define the name in the namespace, we can assume that at
107 // least one of them will define it since otherwise both would have to define only one
108 // namespace, leading to a duplicate error.
109 SingleImports::MaybeOne(_) => *self = SingleImports::AtLeastOne,
110 SingleImports::AtLeastOne => {}
114 fn directive_failed(&mut self) {
116 SingleImports::None => unreachable!(),
117 SingleImports::MaybeOne(_) => *self = SingleImports::None,
118 SingleImports::AtLeastOne => {}
123 impl<'a> NameResolution<'a> {
124 // Returns the binding for the name if it is known or None if it not known.
125 fn binding(&self) -> Option<&'a NameBinding<'a>> {
126 self.binding.and_then(|binding| match self.single_imports {
127 SingleImports::None => Some(binding),
128 _ if !binding.is_glob_import() => Some(binding),
129 _ => None, // The binding could be shadowed by a single import, so it is not known.
134 impl<'a> Resolver<'a> {
135 fn resolution(&self, module: Module<'a>, ident: Ident, ns: Namespace)
136 -> &'a RefCell<NameResolution<'a>> {
137 *module.resolutions.borrow_mut().entry((ident.modern(), ns))
138 .or_insert_with(|| self.arenas.alloc_name_resolution())
141 /// Attempts to resolve `ident` in namespaces `ns` of `module`.
142 /// Invariant: if `record_used` is `Some`, import resolution must be complete.
143 pub fn resolve_ident_in_module_unadjusted(&mut self,
147 restricted_shadowing: bool,
150 -> Result<&'a NameBinding<'a>, Determinacy> {
151 self.populate_module_if_necessary(module);
153 let resolution = self.resolution(module, ident, ns)
155 .map_err(|_| Determined)?; // This happens when there is a cycle of imports
158 if let Some(binding) = resolution.binding {
159 if let Some(shadowed_glob) = resolution.shadows_glob {
160 let name = ident.name;
161 // Forbid expanded shadowing to avoid time travel.
162 if restricted_shadowing &&
163 binding.expansion != Mark::root() &&
164 ns != MacroNS && // In MacroNS, `try_define` always forbids this shadowing
165 binding.def() != shadowed_glob.def() {
166 self.ambiguity_errors.push(AmbiguityError {
176 if self.record_use(ident, ns, binding, path_span) {
177 return Ok(self.dummy_binding);
179 if !self.is_accessible(binding.vis) {
180 self.privacy_errors.push(PrivacyError(path_span, ident.name, binding));
184 return resolution.binding.ok_or(Determined);
187 let check_usable = |this: &mut Self, binding: &'a NameBinding<'a>| {
188 // `extern crate` are always usable for backwards compatability, see issue #37020.
189 let usable = this.is_accessible(binding.vis) || binding.is_extern_crate();
190 if usable { Ok(binding) } else { Err(Determined) }
193 // Items and single imports are not shadowable.
194 if let Some(binding) = resolution.binding {
195 if !binding.is_glob_import() {
196 return check_usable(self, binding);
200 // Check if a single import can still define the name.
201 match resolution.single_imports {
202 SingleImports::AtLeastOne => return Err(Undetermined),
203 SingleImports::MaybeOne(directive) if self.is_accessible(directive.vis.get()) => {
204 let module = match directive.imported_module.get() {
205 Some(module) => module,
206 None => return Err(Undetermined),
208 let ident = match directive.subclass {
209 SingleImport { source, .. } => source,
212 match self.resolve_ident_in_module(module, ident, ns, false, false, path_span) {
213 Err(Determined) => {}
214 _ => return Err(Undetermined),
217 SingleImports::MaybeOne(_) | SingleImports::None => {},
220 let no_unresolved_invocations =
221 restricted_shadowing || module.unresolved_invocations.borrow().is_empty();
222 match resolution.binding {
223 // In `MacroNS`, expanded bindings do not shadow (enforced in `try_define`).
224 Some(binding) if no_unresolved_invocations || ns == MacroNS =>
225 return check_usable(self, binding),
226 None if no_unresolved_invocations => {}
227 _ => return Err(Undetermined),
230 // Check if the globs are determined
231 if restricted_shadowing && module.def().is_some() {
232 return Err(Determined);
234 for directive in module.globs.borrow().iter() {
235 if !self.is_accessible(directive.vis.get()) {
238 let module = unwrap_or!(directive.imported_module.get(), return Err(Undetermined));
239 let (orig_current_module, mut ident) = (self.current_module, ident.modern());
240 match ident.ctxt.glob_adjust(module.expansion, directive.span.ctxt.modern()) {
241 Some(Some(def)) => self.current_module = self.macro_def_scope(def),
245 let result = self.resolve_ident_in_module_unadjusted(
246 module, ident, ns, false, false, path_span,
248 self.current_module = orig_current_module;
249 if let Err(Undetermined) = result {
250 return Err(Undetermined);
257 // Add an import directive to the current module.
258 pub fn add_import_directive(&mut self,
259 module_path: Vec<Ident>,
260 subclass: ImportDirectiveSubclass<'a>,
265 let current_module = self.current_module;
266 let directive = self.arenas.alloc_import_directive(ImportDirective {
267 parent: current_module,
268 module_path: module_path,
269 imported_module: Cell::new(None),
274 expansion: expansion,
275 used: Cell::new(false),
278 self.indeterminate_imports.push(directive);
279 match directive.subclass {
280 SingleImport { target, .. } => {
281 self.per_ns(|this, ns| {
282 let mut resolution = this.resolution(current_module, target, ns).borrow_mut();
283 resolution.single_imports.add_directive(directive);
286 // We don't add prelude imports to the globs since they only affect lexical scopes,
287 // which are not relevant to import resolution.
288 GlobImport { is_prelude: true, .. } => {}
289 GlobImport { .. } => self.current_module.globs.borrow_mut().push(directive),
294 // Given a binding and an import directive that resolves to it,
295 // return the corresponding binding defined by the import directive.
296 pub fn import(&self, binding: &'a NameBinding<'a>, directive: &'a ImportDirective<'a>)
297 -> &'a NameBinding<'a> {
298 let vis = if binding.pseudo_vis().is_at_least(directive.vis.get(), self) ||
299 !directive.is_glob() && binding.is_extern_crate() { // c.f. `PRIVATE_IN_PUBLIC`
305 if let GlobImport { ref max_vis, .. } = directive.subclass {
306 if vis == directive.vis.get() || vis.is_at_least(max_vis.get(), self) {
311 self.arenas.alloc_name_binding(NameBinding {
312 kind: NameBindingKind::Import {
314 directive: directive,
315 used: Cell::new(false),
316 legacy_self_import: false,
318 span: directive.span,
320 expansion: directive.expansion,
324 // Define the name or return the existing binding if there is a collision.
325 pub fn try_define(&mut self,
329 binding: &'a NameBinding<'a>)
330 -> Result<(), &'a NameBinding<'a>> {
331 self.update_resolution(module, ident, ns, |this, resolution| {
332 if let Some(old_binding) = resolution.binding {
333 if binding.is_glob_import() {
334 if !old_binding.is_glob_import() &&
335 !(ns == MacroNS && old_binding.expansion != Mark::root()) {
336 resolution.shadows_glob = Some(binding);
337 } else if binding.def() != old_binding.def() {
338 resolution.binding = Some(this.ambiguity(old_binding, binding));
339 } else if !old_binding.vis.is_at_least(binding.vis, &*this) {
340 // We are glob-importing the same item but with greater visibility.
341 resolution.binding = Some(binding);
343 } else if old_binding.is_glob_import() {
344 if ns == MacroNS && binding.expansion != Mark::root() &&
345 binding.def() != old_binding.def() {
346 resolution.binding = Some(this.ambiguity(binding, old_binding));
348 resolution.binding = Some(binding);
349 resolution.shadows_glob = Some(old_binding);
352 return Err(old_binding);
355 resolution.binding = Some(binding);
362 pub fn ambiguity(&self, b1: &'a NameBinding<'a>, b2: &'a NameBinding<'a>)
363 -> &'a NameBinding<'a> {
364 self.arenas.alloc_name_binding(NameBinding {
365 kind: NameBindingKind::Ambiguity { b1: b1, b2: b2, legacy: false },
366 vis: if b1.vis.is_at_least(b2.vis, self) { b1.vis } else { b2.vis },
368 expansion: Mark::root(),
372 // Use `f` to mutate the resolution of the name in the module.
373 // If the resolution becomes a success, define it in the module's glob importers.
374 fn update_resolution<T, F>(&mut self, module: Module<'a>, ident: Ident, ns: Namespace, f: F)
376 where F: FnOnce(&mut Resolver<'a>, &mut NameResolution<'a>) -> T
378 // Ensure that `resolution` isn't borrowed when defining in the module's glob importers,
379 // during which the resolution might end up getting re-defined via a glob cycle.
381 let mut resolution = &mut *self.resolution(module, ident, ns).borrow_mut();
382 let old_binding = resolution.binding();
384 let t = f(self, resolution);
386 match resolution.binding() {
387 _ if old_binding.is_some() => return t,
389 Some(binding) => match old_binding {
390 Some(old_binding) if old_binding as *const _ == binding as *const _ => return t,
396 // Define `binding` in `module`s glob importers.
397 for directive in module.glob_importers.borrow_mut().iter() {
398 let mut ident = ident.modern();
399 let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
400 directive.span.ctxt.modern()) {
401 Some(Some(def)) => self.macro_def_scope(def),
402 Some(None) => directive.parent,
405 if self.is_accessible_from(binding.vis, scope) {
406 let imported_binding = self.import(binding, directive);
407 let _ = self.try_define(directive.parent, ident, ns, imported_binding);
414 // Define a "dummy" resolution containing a Def::Err as a placeholder for a
416 fn import_dummy_binding(&mut self, directive: &'a ImportDirective<'a>) {
417 if let SingleImport { target, .. } = directive.subclass {
418 let dummy_binding = self.dummy_binding;
419 let dummy_binding = self.import(dummy_binding, directive);
420 self.per_ns(|this, ns| {
421 let _ = this.try_define(directive.parent, target, ns, dummy_binding);
427 pub struct ImportResolver<'a, 'b: 'a> {
428 pub resolver: &'a mut Resolver<'b>,
431 impl<'a, 'b: 'a> ::std::ops::Deref for ImportResolver<'a, 'b> {
432 type Target = Resolver<'b>;
433 fn deref(&self) -> &Resolver<'b> {
438 impl<'a, 'b: 'a> ::std::ops::DerefMut for ImportResolver<'a, 'b> {
439 fn deref_mut(&mut self) -> &mut Resolver<'b> {
444 impl<'a, 'b: 'a> ty::DefIdTree for &'a ImportResolver<'a, 'b> {
445 fn parent(self, id: DefId) -> Option<DefId> {
446 self.resolver.parent(id)
450 impl<'a, 'b:'a> ImportResolver<'a, 'b> {
453 // This is a fixed-point algorithm. We resolve imports until our efforts
454 // are stymied by an unresolved import; then we bail out of the current
455 // module and continue. We terminate successfully once no more imports
456 // remain or unsuccessfully when no forward progress in resolving imports
459 /// Resolves all imports for the crate. This method performs the fixed-
461 pub fn resolve_imports(&mut self) {
462 let mut prev_num_indeterminates = self.indeterminate_imports.len() + 1;
463 while self.indeterminate_imports.len() < prev_num_indeterminates {
464 prev_num_indeterminates = self.indeterminate_imports.len();
465 for import in mem::replace(&mut self.indeterminate_imports, Vec::new()) {
466 match self.resolve_import(&import) {
467 true => self.determined_imports.push(import),
468 false => self.indeterminate_imports.push(import),
474 pub fn finalize_imports(&mut self) {
475 for module in self.arenas.local_modules().iter() {
476 self.finalize_resolutions_in(module);
479 let mut errors = false;
480 for i in 0 .. self.determined_imports.len() {
481 let import = self.determined_imports[i];
482 if let Some(err) = self.finalize_import(import) {
485 // If the error is a single failed import then create a "fake" import
486 // resolution for it so that later resolve stages won't complain.
487 self.import_dummy_binding(import);
488 let path = import_path_to_string(&import.module_path, &import.subclass);
489 let error = ResolutionError::UnresolvedImport(Some((&path, &err)));
490 resolve_error(self.resolver, import.span, error);
494 // Report unresolved imports only if no hard error was already reported
495 // to avoid generating multiple errors on the same import.
497 if let Some(import) = self.indeterminate_imports.iter().next() {
498 let error = ResolutionError::UnresolvedImport(None);
499 resolve_error(self.resolver, import.span, error);
504 /// Attempts to resolve the given import, returning true if its resolution is determined.
505 /// If successful, the resolved bindings are written into the module.
506 fn resolve_import(&mut self, directive: &'b ImportDirective<'b>) -> bool {
507 debug!("(resolving import for module) resolving import `{}::...` in `{}`",
508 names_to_string(&directive.module_path),
509 module_to_string(self.current_module));
511 self.current_module = directive.parent;
513 let module = if let Some(module) = directive.imported_module.get() {
516 let vis = directive.vis.get();
517 // For better failure detection, pretend that the import will not define any names
518 // while resolving its module path.
519 directive.vis.set(ty::Visibility::Invisible);
520 let result = self.resolve_path(&directive.module_path, None, false, directive.span);
521 directive.vis.set(vis);
524 PathResult::Module(module) => module,
525 PathResult::Indeterminate => return false,
530 directive.imported_module.set(Some(module));
531 let (source, target, result, type_ns_only) = match directive.subclass {
532 SingleImport { source, target, ref result, type_ns_only } =>
533 (source, target, result, type_ns_only),
534 GlobImport { .. } => {
535 self.resolve_glob_import(directive);
541 let mut indeterminate = false;
542 self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
543 if let Err(Undetermined) = result[ns].get() {
544 result[ns].set(this.resolve_ident_in_module(module,
554 let parent = directive.parent;
555 match result[ns].get() {
556 Err(Undetermined) => indeterminate = true,
558 this.update_resolution(parent, target, ns, |_, resolution| {
559 resolution.single_imports.directive_failed()
562 Ok(binding) if !binding.is_importable() => {
563 let msg = format!("`{}` is not directly importable", target);
564 struct_span_err!(this.session, directive.span, E0253, "{}", &msg)
565 .span_label(directive.span, "cannot be imported directly")
567 // Do not import this illegal binding. Import a dummy binding and pretend
568 // everything is fine
569 this.import_dummy_binding(directive);
572 let imported_binding = this.import(binding, directive);
573 let conflict = this.try_define(parent, target, ns, imported_binding);
574 if let Err(old_binding) = conflict {
575 this.report_conflict(parent, target, ns, imported_binding, old_binding);
584 // If appropriate, returns an error to report.
585 fn finalize_import(&mut self, directive: &'b ImportDirective<'b>) -> Option<String> {
586 self.current_module = directive.parent;
588 let ImportDirective { ref module_path, span, .. } = *directive;
589 let module_result = self.resolve_path(&module_path, None, true, span);
590 let module = match module_result {
591 PathResult::Module(module) => module,
592 PathResult::Failed(msg, _) => {
593 let (mut self_path, mut self_result) = (module_path.clone(), None);
594 if !self_path.is_empty() && !token::Ident(self_path[0]).is_path_segment_keyword() {
595 self_path[0].name = keywords::SelfValue.name();
596 self_result = Some(self.resolve_path(&self_path, None, false, span));
598 return if let Some(PathResult::Module(..)) = self_result {
599 Some(format!("Did you mean `{}`?", names_to_string(&self_path)))
607 let (ident, result, type_ns_only) = match directive.subclass {
608 SingleImport { source, ref result, type_ns_only, .. } => (source, result, type_ns_only),
609 GlobImport { .. } if module.def_id() == directive.parent.def_id() => {
610 // Importing a module into itself is not allowed.
611 return Some("Cannot glob-import a module into itself.".to_string());
613 GlobImport { is_prelude, ref max_vis } => {
615 max_vis.get() != ty::Visibility::Invisible && // Allow empty globs.
616 !max_vis.get().is_at_least(directive.vis.get(), &*self) {
617 let msg = "A non-empty glob must import something with the glob's visibility";
618 self.session.span_err(directive.span, msg);
625 let mut all_ns_err = true;
626 let mut legacy_self_import = None;
627 self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
628 if let Ok(binding) = result[ns].get() {
630 if this.record_use(ident, ns, binding, directive.span) {
631 this.resolution(module, ident, ns).borrow_mut().binding =
632 Some(this.dummy_binding);
635 } else if let Ok(binding) = this.resolve_ident_in_module(module,
641 legacy_self_import = Some(directive);
642 let binding = this.arenas.alloc_name_binding(NameBinding {
643 kind: NameBindingKind::Import {
645 directive: directive,
646 used: Cell::new(false),
647 legacy_self_import: true,
651 let _ = this.try_define(directive.parent, ident, ns, binding);
655 if let Some(directive) = legacy_self_import {
656 self.warn_legacy_self_import(directive);
659 let mut all_ns_failed = true;
660 self.per_ns(|this, ns| if !type_ns_only || ns == TypeNS {
661 match this.resolve_ident_in_module(module, ident, ns, false, true, span) {
662 Ok(_) => all_ns_failed = false,
667 return if all_ns_failed {
668 let resolutions = module.resolutions.borrow();
669 let names = resolutions.iter().filter_map(|(&(ref i, _), resolution)| {
670 if *i == ident { return None; } // Never suggest the same name
671 match *resolution.borrow() {
672 NameResolution { binding: Some(name_binding), .. } => {
673 match name_binding.kind {
674 NameBindingKind::Import { binding, .. } => {
676 // Never suggest the name that has binding error
677 // i.e. the name that cannot be previously resolved
678 NameBindingKind::Def(Def::Err) => return None,
685 NameResolution { single_imports: SingleImports::None, .. } => None,
690 match find_best_match_for_name(names, &ident.name.as_str(), None) {
691 Some(name) => format!(". Did you mean to use `{}`?", name),
692 None => "".to_owned(),
694 let module_str = module_to_string(module);
695 let msg = if &module_str == "???" {
696 format!("no `{}` in the root{}", ident, lev_suggestion)
698 format!("no `{}` in `{}`{}", ident, module_str, lev_suggestion)
702 // `resolve_ident_in_module` reported a privacy error.
703 self.import_dummy_binding(directive);
708 let mut reexport_error = None;
709 let mut any_successful_reexport = false;
710 self.per_ns(|this, ns| {
711 if let Ok(binding) = result[ns].get() {
712 let vis = directive.vis.get();
713 if !binding.pseudo_vis().is_at_least(vis, &*this) {
714 reexport_error = Some((ns, binding));
716 any_successful_reexport = true;
721 // All namespaces must be re-exported with extra visibility for an error to occur.
722 if !any_successful_reexport {
723 let (ns, binding) = reexport_error.unwrap();
724 if ns == TypeNS && binding.is_extern_crate() {
725 let msg = format!("extern crate `{}` is private, and cannot be reexported \
726 (error E0365), consider declaring with `pub`",
728 self.session.add_lint(PRIVATE_IN_PUBLIC, directive.id, directive.span, msg);
729 } else if ns == TypeNS {
730 struct_span_err!(self.session, directive.span, E0365,
731 "`{}` is private, and cannot be reexported", ident)
732 .span_label(directive.span, format!("reexport of private `{}`", ident))
733 .note(&format!("consider declaring type or module `{}` with `pub`", ident))
736 let msg = format!("`{}` is private, and cannot be reexported", ident);
738 format!("consider marking `{}` as `pub` in the imported module", ident);
739 struct_span_err!(self.session, directive.span, E0364, "{}", &msg)
740 .span_note(directive.span, ¬e_msg)
745 // Record what this import resolves to for later uses in documentation,
746 // this may resolve to either a value or a type, but for documentation
747 // purposes it's good enough to just favor one over the other.
748 self.per_ns(|this, ns| if let Some(binding) = result[ns].get().ok() {
749 this.def_map.entry(directive.id).or_insert(PathResolution::new(binding.def()));
752 debug!("(resolving single import) successfully resolved import");
756 fn resolve_glob_import(&mut self, directive: &'b ImportDirective<'b>) {
757 let module = directive.imported_module.get().unwrap();
758 self.populate_module_if_necessary(module);
760 if let Some(Def::Trait(_)) = module.def() {
761 self.session.span_err(directive.span, "items in traits are not importable.");
763 } else if module.def_id() == directive.parent.def_id() {
765 } else if let GlobImport { is_prelude: true, .. } = directive.subclass {
766 self.prelude = Some(module);
770 // Add to module's glob_importers
771 module.glob_importers.borrow_mut().push(directive);
773 // Ensure that `resolutions` isn't borrowed during `try_define`,
774 // since it might get updated via a glob cycle.
775 let bindings = module.resolutions.borrow().iter().filter_map(|(&ident, resolution)| {
776 resolution.borrow().binding().map(|binding| (ident, binding))
777 }).collect::<Vec<_>>();
778 for ((mut ident, ns), binding) in bindings {
779 let scope = match ident.ctxt.reverse_glob_adjust(module.expansion,
780 directive.span.ctxt.modern()) {
781 Some(Some(def)) => self.macro_def_scope(def),
782 Some(None) => self.current_module,
785 if self.is_accessible_from(binding.pseudo_vis(), scope) {
786 let imported_binding = self.import(binding, directive);
787 let _ = self.try_define(directive.parent, ident, ns, imported_binding);
791 // Record the destination of this import
792 self.record_def(directive.id, PathResolution::new(module.def().unwrap()));
795 // Miscellaneous post-processing, including recording reexports,
796 // reporting conflicts, and reporting unresolved imports.
797 fn finalize_resolutions_in(&mut self, module: Module<'b>) {
798 // Since import resolution is finished, globs will not define any more names.
799 *module.globs.borrow_mut() = Vec::new();
801 let mut reexports = Vec::new();
802 let mut exported_macro_names = FxHashMap();
803 if module as *const _ == self.graph_root as *const _ {
804 let macro_exports = mem::replace(&mut self.macro_exports, Vec::new());
805 for export in macro_exports.into_iter().rev() {
806 if exported_macro_names.insert(export.ident.modern(), export.span).is_none() {
807 reexports.push(export);
812 for (&(ident, ns), resolution) in module.resolutions.borrow().iter() {
813 let resolution = &mut *resolution.borrow_mut();
814 let binding = match resolution.binding {
815 Some(binding) => binding,
819 if binding.vis == ty::Visibility::Public &&
820 (binding.is_import() || binding.is_macro_def()) {
821 let def = binding.def();
823 if !def.def_id().is_local() {
824 self.session.cstore.export_macros(def.def_id().krate);
826 if let Def::Macro(..) = def {
827 if let Some(&span) = exported_macro_names.get(&ident.modern()) {
829 format!("a macro named `{}` has already been exported", ident);
830 self.session.struct_span_err(span, &msg)
831 .span_label(span, format!("`{}` already exported", ident))
832 .span_note(binding.span, "previous macro export here")
836 reexports.push(Export { ident: ident.modern(), def: def, span: binding.span });
841 NameBindingKind::Import { binding: orig_binding, .. } => {
842 if ns == TypeNS && orig_binding.is_variant() &&
843 !orig_binding.vis.is_at_least(binding.vis, &*self) {
844 let msg = format!("variant `{}` is private, and cannot be reexported, \
845 consider declaring its enum as `pub`", ident);
846 self.session.span_err(binding.span, &msg);
849 NameBindingKind::Ambiguity { b1, b2, .. }
850 if b1.is_glob_import() && b2.is_glob_import() => {
851 let (orig_b1, orig_b2) = match (&b1.kind, &b2.kind) {
852 (&NameBindingKind::Import { binding: b1, .. },
853 &NameBindingKind::Import { binding: b2, .. }) => (b1, b2),
856 let (b1, b2) = match (orig_b1.vis, orig_b2.vis) {
857 (ty::Visibility::Public, ty::Visibility::Public) => continue,
858 (ty::Visibility::Public, _) => (b1, b2),
859 (_, ty::Visibility::Public) => (b2, b1),
862 resolution.binding = Some(self.arenas.alloc_name_binding(NameBinding {
863 kind: NameBindingKind::Ambiguity { b1: b1, b2: b2, legacy: true }, ..*b1
870 if reexports.len() > 0 {
871 if let Some(def_id) = module.def_id() {
872 let node_id = self.definitions.as_local_node_id(def_id).unwrap();
873 self.export_map.insert(node_id, reexports);
879 fn import_path_to_string(names: &[Ident], subclass: &ImportDirectiveSubclass) -> String {
880 let global = !names.is_empty() && names[0].name == keywords::CrateRoot.name();
881 let names = if global { &names[1..] } else { names };
882 if names.is_empty() {
883 import_directive_subclass_to_string(subclass)
886 names_to_string(names),
887 import_directive_subclass_to_string(subclass)))
892 fn import_directive_subclass_to_string(subclass: &ImportDirectiveSubclass) -> String {
894 SingleImport { source, .. } => source.to_string(),
895 GlobImport { .. } => "*".to_string(),
896 ExternCrate => "<extern crate>".to_string(),
897 MacroUse => "#[macro_use]".to_string(),