1 //===--- NestedNameSpecifier.h - C++ nested name specifiers -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the NestedNameSpecifier class, which represents
11 // a C++ nested-name-specifier.
13 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_AST_NESTEDNAMESPECIFIER_H
15 #define LLVM_CLANG_AST_NESTEDNAMESPECIFIER_H
17 #include "clang/Basic/Diagnostic.h"
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/ADT/PointerIntPair.h"
24 class NamespaceAliasDecl;
27 struct PrintingPolicy;
32 /// \brief Represents a C++ nested name specifier, such as
33 /// "::std::vector<int>::".
35 /// C++ nested name specifiers are the prefixes to qualified
36 /// namespaces. For example, "foo::" in "foo::x" is a nested name
37 /// specifier. Nested name specifiers are made up of a sequence of
38 /// specifiers, each of which can be a namespace, type, identifier
39 /// (for dependent names), or the global specifier ('::', must be the
41 class NestedNameSpecifier : public llvm::FoldingSetNode {
43 /// \brief Enumeration describing
44 enum StoredSpecifierKind {
46 StoredNamespaceOrAlias = 1,
48 StoredTypeSpecWithTemplate = 3
51 /// \brief The nested name specifier that precedes this nested name
54 /// The pointer is the nested-name-specifier that precedes this
55 /// one. The integer stores one of the first four values of type
57 llvm::PointerIntPair<NestedNameSpecifier *, 2, StoredSpecifierKind> Prefix;
59 /// \brief The last component in the nested name specifier, which
60 /// can be an identifier, a declaration, or a type.
62 /// When the pointer is NULL, this specifier represents the global
63 /// specifier '::'. Otherwise, the pointer is one of
64 /// IdentifierInfo*, Namespace*, or Type*, depending on the kind of
65 /// specifier as encoded within the prefix.
69 /// \brief The kind of specifier that completes this nested name
72 /// \brief An identifier, stored as an IdentifierInfo*.
74 /// \brief A namespace, stored as a NamespaceDecl*.
76 /// \brief A namespace alias, stored as a NamespaceAliasDecl*.
78 /// \brief A type, stored as a Type*.
80 /// \brief A type that was preceded by the 'template' keyword,
81 /// stored as a Type*.
83 /// \brief The global specifier '::'. There is no stored value.
88 /// \brief Builds the global specifier.
89 NestedNameSpecifier() : Prefix(0, StoredIdentifier), Specifier(0) { }
91 /// \brief Copy constructor used internally to clone nested name
93 NestedNameSpecifier(const NestedNameSpecifier &Other)
94 : llvm::FoldingSetNode(Other), Prefix(Other.Prefix),
95 Specifier(Other.Specifier) {
98 NestedNameSpecifier &operator=(const NestedNameSpecifier &); // do not implement
100 /// \brief Either find or insert the given nested name specifier
101 /// mockup in the given context.
102 static NestedNameSpecifier *FindOrInsert(const ASTContext &Context,
103 const NestedNameSpecifier &Mockup);
106 /// \brief Builds a specifier combining a prefix and an identifier.
108 /// The prefix must be dependent, since nested name specifiers
109 /// referencing an identifier are only permitted when the identifier
110 /// cannot be resolved.
111 static NestedNameSpecifier *Create(const ASTContext &Context,
112 NestedNameSpecifier *Prefix,
115 /// \brief Builds a nested name specifier that names a namespace.
116 static NestedNameSpecifier *Create(const ASTContext &Context,
117 NestedNameSpecifier *Prefix,
120 /// \brief Builds a nested name specifier that names a namespace alias.
121 static NestedNameSpecifier *Create(const ASTContext &Context,
122 NestedNameSpecifier *Prefix,
123 NamespaceAliasDecl *Alias);
125 /// \brief Builds a nested name specifier that names a type.
126 static NestedNameSpecifier *Create(const ASTContext &Context,
127 NestedNameSpecifier *Prefix,
128 bool Template, const Type *T);
130 /// \brief Builds a specifier that consists of just an identifier.
132 /// The nested-name-specifier is assumed to be dependent, but has no
133 /// prefix because the prefix is implied by something outside of the
134 /// nested name specifier, e.g., in "x->Base::f", the "x" has a dependent
136 static NestedNameSpecifier *Create(const ASTContext &Context,
139 /// \brief Returns the nested name specifier representing the global
141 static NestedNameSpecifier *GlobalSpecifier(const ASTContext &Context);
143 /// \brief Return the prefix of this nested name specifier.
145 /// The prefix contains all of the parts of the nested name
146 /// specifier that preced this current specifier. For example, for a
147 /// nested name specifier that represents "foo::bar::", the current
148 /// specifier will contain "bar::" and the prefix will contain
150 NestedNameSpecifier *getPrefix() const { return Prefix.getPointer(); }
152 /// \brief Determine what kind of nested name specifier is stored.
153 SpecifierKind getKind() const;
155 /// \brief Retrieve the identifier stored in this nested name
157 IdentifierInfo *getAsIdentifier() const {
158 if (Prefix.getInt() == StoredIdentifier)
159 return (IdentifierInfo *)Specifier;
164 /// \brief Retrieve the namespace stored in this nested name
166 NamespaceDecl *getAsNamespace() const;
168 /// \brief Retrieve the namespace alias stored in this nested name
170 NamespaceAliasDecl *getAsNamespaceAlias() const;
172 /// \brief Retrieve the type stored in this nested name specifier.
173 const Type *getAsType() const {
174 if (Prefix.getInt() == StoredTypeSpec ||
175 Prefix.getInt() == StoredTypeSpecWithTemplate)
176 return (const Type *)Specifier;
181 /// \brief Whether this nested name specifier refers to a dependent
183 bool isDependent() const;
185 /// \brief Whether this nested name specifier involves a template
187 bool isInstantiationDependent() const;
189 /// \brief Whether this nested-name-specifier contains an unexpanded
190 /// parameter pack (for C++0x variadic templates).
191 bool containsUnexpandedParameterPack() const;
193 /// \brief Print this nested name specifier to the given output
195 void print(raw_ostream &OS, const PrintingPolicy &Policy) const;
197 void Profile(llvm::FoldingSetNodeID &ID) const {
198 ID.AddPointer(Prefix.getOpaqueValue());
199 ID.AddPointer(Specifier);
202 /// \brief Dump the nested name specifier to standard output to aid
204 void dump(const LangOptions &LO);
207 /// \brief A C++ nested-name-specifier augmented with source location
209 class NestedNameSpecifierLoc {
210 NestedNameSpecifier *Qualifier;
213 /// \brief Determines the data length for the last component in the
214 /// given nested-name-specifier.
215 static unsigned getLocalDataLength(NestedNameSpecifier *Qualifier);
217 /// \brief Determines the data length for the entire
218 /// nested-name-specifier.
219 static unsigned getDataLength(NestedNameSpecifier *Qualifier);
222 /// \brief Construct an empty nested-name-specifier.
223 NestedNameSpecifierLoc() : Qualifier(0), Data(0) { }
225 /// \brief Construct a nested-name-specifier with source location information
227 NestedNameSpecifierLoc(NestedNameSpecifier *Qualifier, void *Data)
228 : Qualifier(Qualifier), Data(Data) { }
230 /// \brief Evalutes true when this nested-name-specifier location is
232 operator bool() const { return Qualifier; }
234 /// \brief Retrieve the nested-name-specifier to which this instance
236 NestedNameSpecifier *getNestedNameSpecifier() const {
240 /// \brief Retrieve the opaque pointer that refers to source-location data.
241 void *getOpaqueData() const { return Data; }
243 /// \brief Retrieve the source range covering the entirety of this
244 /// nested-name-specifier.
246 /// For example, if this instance refers to a nested-name-specifier
247 /// \c ::std::vector<int>::, the returned source range would cover
248 /// from the initial '::' to the last '::'.
249 SourceRange getSourceRange() const;
251 /// \brief Retrieve the source range covering just the last part of
252 /// this nested-name-specifier, not including the prefix.
254 /// For example, if this instance refers to a nested-name-specifier
255 /// \c ::std::vector<int>::, the returned source range would cover
256 /// from "vector" to the last '::'.
257 SourceRange getLocalSourceRange() const;
259 /// \brief Retrieve the location of the beginning of this
260 /// nested-name-specifier.
261 SourceLocation getBeginLoc() const {
262 return getSourceRange().getBegin();
265 /// \brief Retrieve the location of the end of this
266 /// nested-name-specifier.
267 SourceLocation getEndLoc() const {
268 return getSourceRange().getEnd();
271 /// \brief Retrieve the location of the beginning of this
272 /// component of the nested-name-specifier.
273 SourceLocation getLocalBeginLoc() const {
274 return getLocalSourceRange().getBegin();
277 /// \brief Retrieve the location of the end of this component of the
278 /// nested-name-specifier.
279 SourceLocation getLocalEndLoc() const {
280 return getLocalSourceRange().getEnd();
283 /// \brief Return the prefix of this nested-name-specifier.
285 /// For example, if this instance refers to a nested-name-specifier
286 /// \c ::std::vector<int>::, the prefix is \c ::std::. Note that the
287 /// returned prefix may be empty, if this is the first component of
288 /// the nested-name-specifier.
289 NestedNameSpecifierLoc getPrefix() const {
293 return NestedNameSpecifierLoc(Qualifier->getPrefix(), Data);
296 /// \brief For a nested-name-specifier that refers to a type,
297 /// retrieve the type with source-location information.
298 TypeLoc getTypeLoc() const;
300 /// \brief Determines the data length for the entire
301 /// nested-name-specifier.
302 unsigned getDataLength() const { return getDataLength(Qualifier); }
304 friend bool operator==(NestedNameSpecifierLoc X,
305 NestedNameSpecifierLoc Y) {
306 return X.Qualifier == Y.Qualifier && X.Data == Y.Data;
309 friend bool operator!=(NestedNameSpecifierLoc X,
310 NestedNameSpecifierLoc Y) {
315 /// \brief Class that aids in the construction of nested-name-specifiers along
316 /// with source-location information for all of the components of the
317 /// nested-name-specifier.
318 class NestedNameSpecifierLocBuilder {
319 /// \brief The current representation of the nested-name-specifier we're
321 NestedNameSpecifier *Representation;
323 /// \brief Buffer used to store source-location information for the
324 /// nested-name-specifier.
326 /// Note that we explicitly manage the buffer (rather than using a
327 /// SmallVector) because \c Declarator expects it to be possible to memcpy()
328 /// a \c CXXScopeSpec, and CXXScopeSpec uses a NestedNameSpecifierLocBuilder.
331 /// \brief The size of the buffer used to store source-location information
332 /// for the nested-name-specifier.
335 /// \brief The capacity of the buffer used to store source-location
336 /// information for the nested-name-specifier.
337 unsigned BufferCapacity;
340 NestedNameSpecifierLocBuilder();
342 NestedNameSpecifierLocBuilder(const NestedNameSpecifierLocBuilder &Other);
344 NestedNameSpecifierLocBuilder &
345 operator=(const NestedNameSpecifierLocBuilder &Other);
347 ~NestedNameSpecifierLocBuilder();
349 /// \brief Retrieve the representation of the nested-name-specifier.
350 NestedNameSpecifier *getRepresentation() const { return Representation; }
352 /// \brief Extend the current nested-name-specifier by another
353 /// nested-name-specifier component of the form 'type::'.
355 /// \param Context The AST context in which this nested-name-specifier
358 /// \param TemplateKWLoc The location of the 'template' keyword, if present.
360 /// \param TL The TypeLoc that describes the type preceding the '::'.
362 /// \param ColonColonLoc The location of the trailing '::'.
363 void Extend(ASTContext &Context, SourceLocation TemplateKWLoc, TypeLoc TL,
364 SourceLocation ColonColonLoc);
366 /// \brief Extend the current nested-name-specifier by another
367 /// nested-name-specifier component of the form 'identifier::'.
369 /// \param Context The AST context in which this nested-name-specifier
372 /// \param Identifier The identifier.
374 /// \param IdentifierLoc The location of the identifier.
376 /// \param ColonColonLoc The location of the trailing '::'.
377 void Extend(ASTContext &Context, IdentifierInfo *Identifier,
378 SourceLocation IdentifierLoc, SourceLocation ColonColonLoc);
380 /// \brief Extend the current nested-name-specifier by another
381 /// nested-name-specifier component of the form 'namespace::'.
383 /// \param Context The AST context in which this nested-name-specifier
386 /// \param Namespace The namespace.
388 /// \param NamespaceLoc The location of the namespace name.
390 /// \param ColonColonLoc The location of the trailing '::'.
391 void Extend(ASTContext &Context, NamespaceDecl *Namespace,
392 SourceLocation NamespaceLoc, SourceLocation ColonColonLoc);
394 /// \brief Extend the current nested-name-specifier by another
395 /// nested-name-specifier component of the form 'namespace-alias::'.
397 /// \param Context The AST context in which this nested-name-specifier
400 /// \param Alias The namespace alias.
402 /// \param AliasLoc The location of the namespace alias
405 /// \param ColonColonLoc The location of the trailing '::'.
406 void Extend(ASTContext &Context, NamespaceAliasDecl *Alias,
407 SourceLocation AliasLoc, SourceLocation ColonColonLoc);
409 /// \brief Turn this (empty) nested-name-specifier into the global
410 /// nested-name-specifier '::'.
411 void MakeGlobal(ASTContext &Context, SourceLocation ColonColonLoc);
413 /// \brief Make a new nested-name-specifier from incomplete source-location
416 /// This routine should be used very, very rarely, in cases where we
417 /// need to synthesize a nested-name-specifier. Most code should instead use
418 /// \c Adopt() with a proper \c NestedNameSpecifierLoc.
419 void MakeTrivial(ASTContext &Context, NestedNameSpecifier *Qualifier,
422 /// \brief Adopt an existing nested-name-specifier (with source-range
424 void Adopt(NestedNameSpecifierLoc Other);
426 /// \brief Retrieve the source range covered by this nested-name-specifier.
427 SourceRange getSourceRange() const {
428 return NestedNameSpecifierLoc(Representation, Buffer).getSourceRange();
431 /// \brief Retrieve a nested-name-specifier with location information,
432 /// copied into the given AST context.
434 /// \param Context The context into which this nested-name-specifier will be
436 NestedNameSpecifierLoc getWithLocInContext(ASTContext &Context) const;
438 /// \brief Retrieve a nested-name-specifier with location
439 /// information based on the information in this builder. This loc
440 /// will contain references to the builder's internal data and may
441 /// be invalidated by any change to the builder.
442 NestedNameSpecifierLoc getTemporary() const {
443 return NestedNameSpecifierLoc(Representation, Buffer);
446 /// \brief Clear out this builder, and prepare it to build another
447 /// nested-name-specifier with source-location information.
453 /// \brief Retrieve the underlying buffer.
455 /// \returns A pair containing a pointer to the buffer of source-location
456 /// data and the size of the source-location data that resides in that
458 std::pair<char *, unsigned> getBuffer() const {
459 return std::make_pair(Buffer, BufferSize);
463 /// Insertion operator for diagnostics. This allows sending NestedNameSpecifiers
464 /// into a diagnostic with <<.
465 inline const DiagnosticBuilder &operator<<(const DiagnosticBuilder &DB,
466 NestedNameSpecifier *NNS) {
467 DB.AddTaggedVal(reinterpret_cast<intptr_t>(NNS),
468 DiagnosticsEngine::ak_nestednamespec);