| //===--- ParseTemplate.cpp - Template Parsing -----------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements parsing of C++ templates. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Parse/Parser.h" |
| #include "clang/Parse/ParseDiagnostic.h" |
| #include "clang/Parse/DeclSpec.h" |
| #include "clang/Parse/Scope.h" |
| using namespace clang; |
| |
| /// \brief Parse a template declaration, explicit instantiation, or |
| /// explicit specialization. |
| Parser::DeclPtrTy |
| Parser::ParseDeclarationStartingWithTemplate(unsigned Context, |
| SourceLocation &DeclEnd, |
| AccessSpecifier AS) { |
| if (Tok.is(tok::kw_template) && NextToken().isNot(tok::less)) |
| return ParseExplicitInstantiation(ConsumeToken(), DeclEnd); |
| |
| return ParseTemplateDeclarationOrSpecialization(Context, DeclEnd, AS); |
| } |
| |
| /// \brief Parse a template declaration or an explicit specialization. |
| /// |
| /// Template declarations include one or more template parameter lists |
| /// and either the function or class template declaration. Explicit |
| /// specializations contain one or more 'template < >' prefixes |
| /// followed by a (possibly templated) declaration. Since the |
| /// syntactic form of both features is nearly identical, we parse all |
| /// of the template headers together and let semantic analysis sort |
| /// the declarations from the explicit specializations. |
| /// |
| /// template-declaration: [C++ temp] |
| /// 'export'[opt] 'template' '<' template-parameter-list '>' declaration |
| /// |
| /// explicit-specialization: [ C++ temp.expl.spec] |
| /// 'template' '<' '>' declaration |
| Parser::DeclPtrTy |
| Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context, |
| SourceLocation &DeclEnd, |
| AccessSpecifier AS) { |
| assert((Tok.is(tok::kw_export) || Tok.is(tok::kw_template)) && |
| "Token does not start a template declaration."); |
| |
| // Enter template-parameter scope. |
| ParseScope TemplateParmScope(this, Scope::TemplateParamScope); |
| |
| // Parse multiple levels of template headers within this template |
| // parameter scope, e.g., |
| // |
| // template<typename T> |
| // template<typename U> |
| // class A<T>::B { ... }; |
| // |
| // We parse multiple levels non-recursively so that we can build a |
| // single data structure containing all of the template parameter |
| // lists to easily differentiate between the case above and: |
| // |
| // template<typename T> |
| // class A { |
| // template<typename U> class B; |
| // }; |
| // |
| // In the first case, the action for declaring A<T>::B receives |
| // both template parameter lists. In the second case, the action for |
| // defining A<T>::B receives just the inner template parameter list |
| // (and retrieves the outer template parameter list from its |
| // context). |
| bool isSpecialization = true; |
| TemplateParameterLists ParamLists; |
| do { |
| // Consume the 'export', if any. |
| SourceLocation ExportLoc; |
| if (Tok.is(tok::kw_export)) { |
| ExportLoc = ConsumeToken(); |
| } |
| |
| // Consume the 'template', which should be here. |
| SourceLocation TemplateLoc; |
| if (Tok.is(tok::kw_template)) { |
| TemplateLoc = ConsumeToken(); |
| } else { |
| Diag(Tok.getLocation(), diag::err_expected_template); |
| return DeclPtrTy(); |
| } |
| |
| // Parse the '<' template-parameter-list '>' |
| SourceLocation LAngleLoc, RAngleLoc; |
| TemplateParameterList TemplateParams; |
| if (ParseTemplateParameters(ParamLists.size(), TemplateParams, LAngleLoc, |
| RAngleLoc)) { |
| // Skip until the semi-colon or a }. |
| SkipUntil(tok::r_brace, true, true); |
| if (Tok.is(tok::semi)) |
| ConsumeToken(); |
| return DeclPtrTy(); |
| } |
| |
| if (!TemplateParams.empty()) |
| isSpecialization = false; |
| |
| ParamLists.push_back( |
| Actions.ActOnTemplateParameterList(ParamLists.size(), ExportLoc, |
| TemplateLoc, LAngleLoc, |
| TemplateParams.data(), |
| TemplateParams.size(), RAngleLoc)); |
| } while (Tok.is(tok::kw_export) || Tok.is(tok::kw_template)); |
| |
| // Parse the actual template declaration. |
| return ParseSingleDeclarationAfterTemplate(Context, |
| ParsedTemplateInfo(&ParamLists, |
| isSpecialization), |
| DeclEnd, AS); |
| } |
| |
| /// \brief Parse a single declaration that declares a template, |
| /// template specialization, or explicit instantiation of a template. |
| /// |
| /// \param TemplateParams if non-NULL, the template parameter lists |
| /// that preceded this declaration. In this case, the declaration is a |
| /// template declaration, out-of-line definition of a template, or an |
| /// explicit template specialization. When NULL, the declaration is an |
| /// explicit template instantiation. |
| /// |
| /// \param TemplateLoc when TemplateParams is NULL, the location of |
| /// the 'template' keyword that indicates that we have an explicit |
| /// template instantiation. |
| /// |
| /// \param DeclEnd will receive the source location of the last token |
| /// within this declaration. |
| /// |
| /// \param AS the access specifier associated with this |
| /// declaration. Will be AS_none for namespace-scope declarations. |
| /// |
| /// \returns the new declaration. |
| Parser::DeclPtrTy |
| Parser::ParseSingleDeclarationAfterTemplate( |
| unsigned Context, |
| const ParsedTemplateInfo &TemplateInfo, |
| SourceLocation &DeclEnd, |
| AccessSpecifier AS) { |
| assert(TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate && |
| "Template information required"); |
| |
| if (Context == Declarator::MemberContext) { |
| // We are parsing a member template. |
| ParseCXXClassMemberDeclaration(AS, TemplateInfo); |
| return DeclPtrTy::make((void*)0); |
| } |
| |
| // Parse the declaration specifiers. |
| DeclSpec DS; |
| // FIXME: Pass TemplateLoc through for explicit template instantiations |
| ParseDeclarationSpecifiers(DS, TemplateInfo, AS); |
| |
| if (Tok.is(tok::semi)) { |
| DeclEnd = ConsumeToken(); |
| return Actions.ParsedFreeStandingDeclSpec(CurScope, DS); |
| } |
| |
| // Parse the declarator. |
| Declarator DeclaratorInfo(DS, (Declarator::TheContext)Context); |
| ParseDeclarator(DeclaratorInfo); |
| // Error parsing the declarator? |
| if (!DeclaratorInfo.hasName()) { |
| // If so, skip until the semi-colon or a }. |
| SkipUntil(tok::r_brace, true, true); |
| if (Tok.is(tok::semi)) |
| ConsumeToken(); |
| return DeclPtrTy(); |
| } |
| |
| // If we have a declaration or declarator list, handle it. |
| if (isDeclarationAfterDeclarator()) { |
| // Parse this declaration. |
| DeclPtrTy ThisDecl = ParseDeclarationAfterDeclarator(DeclaratorInfo, |
| TemplateInfo); |
| |
| if (Tok.is(tok::comma)) { |
| Diag(Tok, diag::err_multiple_template_declarators) |
| << (int)TemplateInfo.Kind; |
| SkipUntil(tok::semi, true, false); |
| return ThisDecl; |
| } |
| |
| // Eat the semi colon after the declaration. |
| ExpectAndConsume(tok::semi, diag::err_expected_semi_declaration); |
| return ThisDecl; |
| } |
| |
| if (DeclaratorInfo.isFunctionDeclarator() && |
| isStartOfFunctionDefinition()) { |
| if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) { |
| Diag(Tok, diag::err_function_declared_typedef); |
| |
| if (Tok.is(tok::l_brace)) { |
| // This recovery skips the entire function body. It would be nice |
| // to simply call ParseFunctionDefinition() below, however Sema |
| // assumes the declarator represents a function, not a typedef. |
| ConsumeBrace(); |
| SkipUntil(tok::r_brace, true); |
| } else { |
| SkipUntil(tok::semi); |
| } |
| return DeclPtrTy(); |
| } |
| return ParseFunctionDefinition(DeclaratorInfo, TemplateInfo); |
| } |
| |
| if (DeclaratorInfo.isFunctionDeclarator()) |
| Diag(Tok, diag::err_expected_fn_body); |
| else |
| Diag(Tok, diag::err_invalid_token_after_toplevel_declarator); |
| SkipUntil(tok::semi); |
| return DeclPtrTy(); |
| } |
| |
| /// ParseTemplateParameters - Parses a template-parameter-list enclosed in |
| /// angle brackets. Depth is the depth of this template-parameter-list, which |
| /// is the number of template headers directly enclosing this template header. |
| /// TemplateParams is the current list of template parameters we're building. |
| /// The template parameter we parse will be added to this list. LAngleLoc and |
| /// RAngleLoc will receive the positions of the '<' and '>', respectively, |
| /// that enclose this template parameter list. |
| /// |
| /// \returns true if an error occurred, false otherwise. |
| bool Parser::ParseTemplateParameters(unsigned Depth, |
| TemplateParameterList &TemplateParams, |
| SourceLocation &LAngleLoc, |
| SourceLocation &RAngleLoc) { |
| // Get the template parameter list. |
| if(!Tok.is(tok::less)) { |
| Diag(Tok.getLocation(), diag::err_expected_less_after) << "template"; |
| return true; |
| } |
| LAngleLoc = ConsumeToken(); |
| |
| // Try to parse the template parameter list. |
| if (Tok.is(tok::greater)) |
| RAngleLoc = ConsumeToken(); |
| else if(ParseTemplateParameterList(Depth, TemplateParams)) { |
| if(!Tok.is(tok::greater)) { |
| Diag(Tok.getLocation(), diag::err_expected_greater); |
| return true; |
| } |
| RAngleLoc = ConsumeToken(); |
| } |
| return false; |
| } |
| |
| /// ParseTemplateParameterList - Parse a template parameter list. If |
| /// the parsing fails badly (i.e., closing bracket was left out), this |
| /// will try to put the token stream in a reasonable position (closing |
| /// a statement, etc.) and return false. |
| /// |
| /// template-parameter-list: [C++ temp] |
| /// template-parameter |
| /// template-parameter-list ',' template-parameter |
| bool |
| Parser::ParseTemplateParameterList(unsigned Depth, |
| TemplateParameterList &TemplateParams) { |
| while(1) { |
| if (DeclPtrTy TmpParam |
| = ParseTemplateParameter(Depth, TemplateParams.size())) { |
| TemplateParams.push_back(TmpParam); |
| } else { |
| // If we failed to parse a template parameter, skip until we find |
| // a comma or closing brace. |
| SkipUntil(tok::comma, tok::greater, true, true); |
| } |
| |
| // Did we find a comma or the end of the template parmeter list? |
| if(Tok.is(tok::comma)) { |
| ConsumeToken(); |
| } else if(Tok.is(tok::greater)) { |
| // Don't consume this... that's done by template parser. |
| break; |
| } else { |
| // Somebody probably forgot to close the template. Skip ahead and |
| // try to get out of the expression. This error is currently |
| // subsumed by whatever goes on in ParseTemplateParameter. |
| // TODO: This could match >>, and it would be nice to avoid those |
| // silly errors with template <vec<T>>. |
| // Diag(Tok.getLocation(), diag::err_expected_comma_greater); |
| SkipUntil(tok::greater, true, true); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /// ParseTemplateParameter - Parse a template-parameter (C++ [temp.param]). |
| /// |
| /// template-parameter: [C++ temp.param] |
| /// type-parameter |
| /// parameter-declaration |
| /// |
| /// type-parameter: (see below) |
| /// 'class' ...[opt][C++0x] identifier[opt] |
| /// 'class' identifier[opt] '=' type-id |
| /// 'typename' ...[opt][C++0x] identifier[opt] |
| /// 'typename' identifier[opt] '=' type-id |
| /// 'template' ...[opt][C++0x] '<' template-parameter-list '>' 'class' identifier[opt] |
| /// 'template' '<' template-parameter-list '>' 'class' identifier[opt] = id-expression |
| Parser::DeclPtrTy |
| Parser::ParseTemplateParameter(unsigned Depth, unsigned Position) { |
| if(Tok.is(tok::kw_class) || |
| (Tok.is(tok::kw_typename) && |
| // FIXME: Next token has not been annotated! |
| NextToken().isNot(tok::annot_typename))) { |
| return ParseTypeParameter(Depth, Position); |
| } |
| |
| if(Tok.is(tok::kw_template)) |
| return ParseTemplateTemplateParameter(Depth, Position); |
| |
| // If it's none of the above, then it must be a parameter declaration. |
| // NOTE: This will pick up errors in the closure of the template parameter |
| // list (e.g., template < ; Check here to implement >> style closures. |
| return ParseNonTypeTemplateParameter(Depth, Position); |
| } |
| |
| /// ParseTypeParameter - Parse a template type parameter (C++ [temp.param]). |
| /// Other kinds of template parameters are parsed in |
| /// ParseTemplateTemplateParameter and ParseNonTypeTemplateParameter. |
| /// |
| /// type-parameter: [C++ temp.param] |
| /// 'class' ...[opt][C++0x] identifier[opt] |
| /// 'class' identifier[opt] '=' type-id |
| /// 'typename' ...[opt][C++0x] identifier[opt] |
| /// 'typename' identifier[opt] '=' type-id |
| Parser::DeclPtrTy Parser::ParseTypeParameter(unsigned Depth, unsigned Position){ |
| assert((Tok.is(tok::kw_class) || Tok.is(tok::kw_typename)) && |
| "A type-parameter starts with 'class' or 'typename'"); |
| |
| // Consume the 'class' or 'typename' keyword. |
| bool TypenameKeyword = Tok.is(tok::kw_typename); |
| SourceLocation KeyLoc = ConsumeToken(); |
| |
| // Grab the ellipsis (if given). |
| bool Ellipsis = false; |
| SourceLocation EllipsisLoc; |
| if (Tok.is(tok::ellipsis)) { |
| Ellipsis = true; |
| EllipsisLoc = ConsumeToken(); |
| |
| if (!getLang().CPlusPlus0x) |
| Diag(EllipsisLoc, diag::err_variadic_templates); |
| } |
| |
| // Grab the template parameter name (if given) |
| SourceLocation NameLoc; |
| IdentifierInfo* ParamName = 0; |
| if(Tok.is(tok::identifier)) { |
| ParamName = Tok.getIdentifierInfo(); |
| NameLoc = ConsumeToken(); |
| } else if(Tok.is(tok::equal) || Tok.is(tok::comma) || |
| Tok.is(tok::greater)) { |
| // Unnamed template parameter. Don't have to do anything here, just |
| // don't consume this token. |
| } else { |
| Diag(Tok.getLocation(), diag::err_expected_ident); |
| return DeclPtrTy(); |
| } |
| |
| DeclPtrTy TypeParam = Actions.ActOnTypeParameter(CurScope, TypenameKeyword, |
| Ellipsis, EllipsisLoc, |
| KeyLoc, ParamName, NameLoc, |
| Depth, Position); |
| |
| // Grab a default type id (if given). |
| if(Tok.is(tok::equal)) { |
| SourceLocation EqualLoc = ConsumeToken(); |
| SourceLocation DefaultLoc = Tok.getLocation(); |
| TypeResult DefaultType = ParseTypeName(); |
| if (!DefaultType.isInvalid()) |
| Actions.ActOnTypeParameterDefault(TypeParam, EqualLoc, DefaultLoc, |
| DefaultType.get()); |
| } |
| |
| return TypeParam; |
| } |
| |
| /// ParseTemplateTemplateParameter - Handle the parsing of template |
| /// template parameters. |
| /// |
| /// type-parameter: [C++ temp.param] |
| /// 'template' '<' template-parameter-list '>' 'class' identifier[opt] |
| /// 'template' '<' template-parameter-list '>' 'class' identifier[opt] = id-expression |
| Parser::DeclPtrTy |
| Parser::ParseTemplateTemplateParameter(unsigned Depth, unsigned Position) { |
| assert(Tok.is(tok::kw_template) && "Expected 'template' keyword"); |
| |
| // Handle the template <...> part. |
| SourceLocation TemplateLoc = ConsumeToken(); |
| TemplateParameterList TemplateParams; |
| SourceLocation LAngleLoc, RAngleLoc; |
| { |
| ParseScope TemplateParmScope(this, Scope::TemplateParamScope); |
| if(ParseTemplateParameters(Depth + 1, TemplateParams, LAngleLoc, |
| RAngleLoc)) { |
| return DeclPtrTy(); |
| } |
| } |
| |
| // Generate a meaningful error if the user forgot to put class before the |
| // identifier, comma, or greater. |
| if(!Tok.is(tok::kw_class)) { |
| Diag(Tok.getLocation(), diag::err_expected_class_before) |
| << PP.getSpelling(Tok); |
| return DeclPtrTy(); |
| } |
| SourceLocation ClassLoc = ConsumeToken(); |
| |
| // Get the identifier, if given. |
| SourceLocation NameLoc; |
| IdentifierInfo* ParamName = 0; |
| if(Tok.is(tok::identifier)) { |
| ParamName = Tok.getIdentifierInfo(); |
| NameLoc = ConsumeToken(); |
| } else if(Tok.is(tok::equal) || Tok.is(tok::comma) || Tok.is(tok::greater)) { |
| // Unnamed template parameter. Don't have to do anything here, just |
| // don't consume this token. |
| } else { |
| Diag(Tok.getLocation(), diag::err_expected_ident); |
| return DeclPtrTy(); |
| } |
| |
| TemplateParamsTy *ParamList = |
| Actions.ActOnTemplateParameterList(Depth, SourceLocation(), |
| TemplateLoc, LAngleLoc, |
| &TemplateParams[0], |
| TemplateParams.size(), |
| RAngleLoc); |
| |
| Parser::DeclPtrTy Param |
| = Actions.ActOnTemplateTemplateParameter(CurScope, TemplateLoc, |
| ParamList, ParamName, |
| NameLoc, Depth, Position); |
| |
| // Get the a default value, if given. |
| if (Tok.is(tok::equal)) { |
| SourceLocation EqualLoc = ConsumeToken(); |
| OwningExprResult DefaultExpr = ParseCXXIdExpression(); |
| if (DefaultExpr.isInvalid()) |
| return Param; |
| else if (Param) |
| Actions.ActOnTemplateTemplateParameterDefault(Param, EqualLoc, |
| move(DefaultExpr)); |
| } |
| |
| return Param; |
| } |
| |
| /// ParseNonTypeTemplateParameter - Handle the parsing of non-type |
| /// template parameters (e.g., in "template<int Size> class array;"). |
| /// |
| /// template-parameter: |
| /// ... |
| /// parameter-declaration |
| /// |
| /// NOTE: It would be ideal to simply call out to ParseParameterDeclaration(), |
| /// but that didn't work out to well. Instead, this tries to recrate the basic |
| /// parsing of parameter declarations, but tries to constrain it for template |
| /// parameters. |
| /// FIXME: We need to make a ParseParameterDeclaration that works for |
| /// non-type template parameters and normal function parameters. |
| Parser::DeclPtrTy |
| Parser::ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position) { |
| SourceLocation StartLoc = Tok.getLocation(); |
| |
| // Parse the declaration-specifiers (i.e., the type). |
| // FIXME: The type should probably be restricted in some way... Not all |
| // declarators (parts of declarators?) are accepted for parameters. |
| DeclSpec DS; |
| ParseDeclarationSpecifiers(DS); |
| |
| // Parse this as a typename. |
| Declarator ParamDecl(DS, Declarator::TemplateParamContext); |
| ParseDeclarator(ParamDecl); |
| if (DS.getTypeSpecType() == DeclSpec::TST_unspecified && !DS.getTypeRep()) { |
| // This probably shouldn't happen - and it's more of a Sema thing, but |
| // basically we didn't parse the type name because we couldn't associate |
| // it with an AST node. we should just skip to the comma or greater. |
| // TODO: This is currently a placeholder for some kind of Sema Error. |
| Diag(Tok.getLocation(), diag::err_parse_error); |
| SkipUntil(tok::comma, tok::greater, true, true); |
| return DeclPtrTy(); |
| } |
| |
| // Create the parameter. |
| DeclPtrTy Param = Actions.ActOnNonTypeTemplateParameter(CurScope, ParamDecl, |
| Depth, Position); |
| |
| // If there is a default value, parse it. |
| if (Tok.is(tok::equal)) { |
| SourceLocation EqualLoc = ConsumeToken(); |
| |
| // C++ [temp.param]p15: |
| // When parsing a default template-argument for a non-type |
| // template-parameter, the first non-nested > is taken as the |
| // end of the template-parameter-list rather than a greater-than |
| // operator. |
| GreaterThanIsOperatorScope G(GreaterThanIsOperator, false); |
| |
| OwningExprResult DefaultArg = ParseAssignmentExpression(); |
| if (DefaultArg.isInvalid()) |
| SkipUntil(tok::comma, tok::greater, true, true); |
| else if (Param) |
| Actions.ActOnNonTypeTemplateParameterDefault(Param, EqualLoc, |
| move(DefaultArg)); |
| } |
| |
| return Param; |
| } |
| |
| /// \brief Parses a template-id that after the template name has |
| /// already been parsed. |
| /// |
| /// This routine takes care of parsing the enclosed template argument |
| /// list ('<' template-parameter-list [opt] '>') and placing the |
| /// results into a form that can be transferred to semantic analysis. |
| /// |
| /// \param Template the template declaration produced by isTemplateName |
| /// |
| /// \param TemplateNameLoc the source location of the template name |
| /// |
| /// \param SS if non-NULL, the nested-name-specifier preceding the |
| /// template name. |
| /// |
| /// \param ConsumeLastToken if true, then we will consume the last |
| /// token that forms the template-id. Otherwise, we will leave the |
| /// last token in the stream (e.g., so that it can be replaced with an |
| /// annotation token). |
| bool |
| Parser::ParseTemplateIdAfterTemplateName(TemplateTy Template, |
| SourceLocation TemplateNameLoc, |
| const CXXScopeSpec *SS, |
| bool ConsumeLastToken, |
| SourceLocation &LAngleLoc, |
| TemplateArgList &TemplateArgs, |
| TemplateArgIsTypeList &TemplateArgIsType, |
| TemplateArgLocationList &TemplateArgLocations, |
| SourceLocation &RAngleLoc) { |
| assert(Tok.is(tok::less) && "Must have already parsed the template-name"); |
| |
| // Consume the '<'. |
| LAngleLoc = ConsumeToken(); |
| |
| // Parse the optional template-argument-list. |
| bool Invalid = false; |
| { |
| GreaterThanIsOperatorScope G(GreaterThanIsOperator, false); |
| if (Tok.isNot(tok::greater)) |
| Invalid = ParseTemplateArgumentList(TemplateArgs, TemplateArgIsType, |
| TemplateArgLocations); |
| |
| if (Invalid) { |
| // Try to find the closing '>'. |
| SkipUntil(tok::greater, true, !ConsumeLastToken); |
| |
| return true; |
| } |
| } |
| |
| if (Tok.isNot(tok::greater) && Tok.isNot(tok::greatergreater)) |
| return true; |
| |
| // Determine the location of the '>' or '>>'. Only consume this |
| // token if the caller asked us to. |
| RAngleLoc = Tok.getLocation(); |
| |
| if (Tok.is(tok::greatergreater)) { |
| if (!getLang().CPlusPlus0x) { |
| const char *ReplaceStr = "> >"; |
| if (NextToken().is(tok::greater) || NextToken().is(tok::greatergreater)) |
| ReplaceStr = "> > "; |
| |
| Diag(Tok.getLocation(), diag::err_two_right_angle_brackets_need_space) |
| << CodeModificationHint::CreateReplacement( |
| SourceRange(Tok.getLocation()), ReplaceStr); |
| } |
| |
| Tok.setKind(tok::greater); |
| if (!ConsumeLastToken) { |
| // Since we're not supposed to consume the '>>' token, we need |
| // to insert a second '>' token after the first. |
| PP.EnterToken(Tok); |
| } |
| } else if (ConsumeLastToken) |
| ConsumeToken(); |
| |
| return false; |
| } |
| |
| /// \brief Replace the tokens that form a simple-template-id with an |
| /// annotation token containing the complete template-id. |
| /// |
| /// The first token in the stream must be the name of a template that |
| /// is followed by a '<'. This routine will parse the complete |
| /// simple-template-id and replace the tokens with a single annotation |
| /// token with one of two different kinds: if the template-id names a |
| /// type (and \p AllowTypeAnnotation is true), the annotation token is |
| /// a type annotation that includes the optional nested-name-specifier |
| /// (\p SS). Otherwise, the annotation token is a template-id |
| /// annotation that does not include the optional |
| /// nested-name-specifier. |
| /// |
| /// \param Template the declaration of the template named by the first |
| /// token (an identifier), as returned from \c Action::isTemplateName(). |
| /// |
| /// \param TemplateNameKind the kind of template that \p Template |
| /// refers to, as returned from \c Action::isTemplateName(). |
| /// |
| /// \param SS if non-NULL, the nested-name-specifier that precedes |
| /// this template name. |
| /// |
| /// \param TemplateKWLoc if valid, specifies that this template-id |
| /// annotation was preceded by the 'template' keyword and gives the |
| /// location of that keyword. If invalid (the default), then this |
| /// template-id was not preceded by a 'template' keyword. |
| /// |
| /// \param AllowTypeAnnotation if true (the default), then a |
| /// simple-template-id that refers to a class template, template |
| /// template parameter, or other template that produces a type will be |
| /// replaced with a type annotation token. Otherwise, the |
| /// simple-template-id is always replaced with a template-id |
| /// annotation token. |
| /// |
| /// If an unrecoverable parse error occurs and no annotation token can be |
| /// formed, this function returns true. |
| /// |
| bool Parser::AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK, |
| const CXXScopeSpec *SS, |
| SourceLocation TemplateKWLoc, |
| bool AllowTypeAnnotation) { |
| assert(getLang().CPlusPlus && "Can only annotate template-ids in C++"); |
| assert(Template && Tok.is(tok::identifier) && NextToken().is(tok::less) && |
| "Parser isn't at the beginning of a template-id"); |
| |
| // Consume the template-name. |
| IdentifierInfo *Name = Tok.getIdentifierInfo(); |
| SourceLocation TemplateNameLoc = ConsumeToken(); |
| |
| // Parse the enclosed template argument list. |
| SourceLocation LAngleLoc, RAngleLoc; |
| TemplateArgList TemplateArgs; |
| TemplateArgIsTypeList TemplateArgIsType; |
| TemplateArgLocationList TemplateArgLocations; |
| bool Invalid = ParseTemplateIdAfterTemplateName(Template, TemplateNameLoc, |
| SS, false, LAngleLoc, |
| TemplateArgs, |
| TemplateArgIsType, |
| TemplateArgLocations, |
| RAngleLoc); |
| |
| if (Invalid) { |
| // If we failed to parse the template ID but skipped ahead to a >, we're not |
| // going to be able to form a token annotation. Eat the '>' if present. |
| if (Tok.is(tok::greater)) |
| ConsumeToken(); |
| return true; |
| } |
| |
| ASTTemplateArgsPtr TemplateArgsPtr(Actions, TemplateArgs.data(), |
| TemplateArgIsType.data(), |
| TemplateArgs.size()); |
| |
| // Build the annotation token. |
| if (TNK == TNK_Type_template && AllowTypeAnnotation) { |
| Action::TypeResult Type |
| = Actions.ActOnTemplateIdType(Template, TemplateNameLoc, |
| LAngleLoc, TemplateArgsPtr, |
| &TemplateArgLocations[0], |
| RAngleLoc); |
| if (Type.isInvalid()) { |
| // If we failed to parse the template ID but skipped ahead to a >, we're not |
| // going to be able to form a token annotation. Eat the '>' if present. |
| if (Tok.is(tok::greater)) |
| ConsumeToken(); |
| return true; |
| } |
| |
| Tok.setKind(tok::annot_typename); |
| Tok.setAnnotationValue(Type.get()); |
| if (SS && SS->isNotEmpty()) |
| Tok.setLocation(SS->getBeginLoc()); |
| else if (TemplateKWLoc.isValid()) |
| Tok.setLocation(TemplateKWLoc); |
| else |
| Tok.setLocation(TemplateNameLoc); |
| } else { |
| // Build a template-id annotation token that can be processed |
| // later. |
| Tok.setKind(tok::annot_template_id); |
| TemplateIdAnnotation *TemplateId |
| = TemplateIdAnnotation::Allocate(TemplateArgs.size()); |
| TemplateId->TemplateNameLoc = TemplateNameLoc; |
| TemplateId->Name = Name; |
| TemplateId->Template = Template.getAs<void*>(); |
| TemplateId->Kind = TNK; |
| TemplateId->LAngleLoc = LAngleLoc; |
| TemplateId->RAngleLoc = RAngleLoc; |
| void **Args = TemplateId->getTemplateArgs(); |
| bool *ArgIsType = TemplateId->getTemplateArgIsType(); |
| SourceLocation *ArgLocs = TemplateId->getTemplateArgLocations(); |
| for (unsigned Arg = 0, ArgEnd = TemplateArgs.size(); Arg != ArgEnd; ++Arg) { |
| Args[Arg] = TemplateArgs[Arg]; |
| ArgIsType[Arg] = TemplateArgIsType[Arg]; |
| ArgLocs[Arg] = TemplateArgLocations[Arg]; |
| } |
| Tok.setAnnotationValue(TemplateId); |
| if (TemplateKWLoc.isValid()) |
| Tok.setLocation(TemplateKWLoc); |
| else |
| Tok.setLocation(TemplateNameLoc); |
| |
| TemplateArgsPtr.release(); |
| } |
| |
| // Common fields for the annotation token |
| Tok.setAnnotationEndLoc(RAngleLoc); |
| |
| // In case the tokens were cached, have Preprocessor replace them with the |
| // annotation token. |
| PP.AnnotateCachedTokens(Tok); |
| return false; |
| } |
| |
| /// \brief Replaces a template-id annotation token with a type |
| /// annotation token. |
| /// |
| /// If there was a failure when forming the type from the template-id, |
| /// a type annotation token will still be created, but will have a |
| /// NULL type pointer to signify an error. |
| void Parser::AnnotateTemplateIdTokenAsType(const CXXScopeSpec *SS) { |
| assert(Tok.is(tok::annot_template_id) && "Requires template-id tokens"); |
| |
| TemplateIdAnnotation *TemplateId |
| = static_cast<TemplateIdAnnotation *>(Tok.getAnnotationValue()); |
| assert((TemplateId->Kind == TNK_Type_template || |
| TemplateId->Kind == TNK_Dependent_template_name) && |
| "Only works for type and dependent templates"); |
| |
| ASTTemplateArgsPtr TemplateArgsPtr(Actions, |
| TemplateId->getTemplateArgs(), |
| TemplateId->getTemplateArgIsType(), |
| TemplateId->NumArgs); |
| |
| Action::TypeResult Type |
| = Actions.ActOnTemplateIdType(TemplateTy::make(TemplateId->Template), |
| TemplateId->TemplateNameLoc, |
| TemplateId->LAngleLoc, |
| TemplateArgsPtr, |
| TemplateId->getTemplateArgLocations(), |
| TemplateId->RAngleLoc); |
| // Create the new "type" annotation token. |
| Tok.setKind(tok::annot_typename); |
| Tok.setAnnotationValue(Type.isInvalid()? 0 : Type.get()); |
| if (SS && SS->isNotEmpty()) // it was a C++ qualified type name. |
| Tok.setLocation(SS->getBeginLoc()); |
| |
| // We might be backtracking, in which case we need to replace the |
| // template-id annotation token with the type annotation within the |
| // set of cached tokens. That way, we won't try to form the same |
| // class template specialization again. |
| PP.ReplaceLastTokenWithAnnotation(Tok); |
| TemplateId->Destroy(); |
| } |
| |
| /// ParseTemplateArgument - Parse a C++ template argument (C++ [temp.names]). |
| /// |
| /// template-argument: [C++ 14.2] |
| /// constant-expression |
| /// type-id |
| /// id-expression |
| void *Parser::ParseTemplateArgument(bool &ArgIsType) { |
| // C++ [temp.arg]p2: |
| // In a template-argument, an ambiguity between a type-id and an |
| // expression is resolved to a type-id, regardless of the form of |
| // the corresponding template-parameter. |
| // |
| // Therefore, we initially try to parse a type-id. |
| if (isCXXTypeId(TypeIdAsTemplateArgument)) { |
| ArgIsType = true; |
| TypeResult TypeArg = ParseTypeName(); |
| if (TypeArg.isInvalid()) |
| return 0; |
| return TypeArg.get(); |
| } |
| |
| OwningExprResult ExprArg = ParseConstantExpression(); |
| if (ExprArg.isInvalid() || !ExprArg.get()) |
| return 0; |
| |
| ArgIsType = false; |
| return ExprArg.release(); |
| } |
| |
| /// ParseTemplateArgumentList - Parse a C++ template-argument-list |
| /// (C++ [temp.names]). Returns true if there was an error. |
| /// |
| /// template-argument-list: [C++ 14.2] |
| /// template-argument |
| /// template-argument-list ',' template-argument |
| bool |
| Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs, |
| TemplateArgIsTypeList &TemplateArgIsType, |
| TemplateArgLocationList &TemplateArgLocations) { |
| while (true) { |
| bool IsType = false; |
| SourceLocation Loc = Tok.getLocation(); |
| void *Arg = ParseTemplateArgument(IsType); |
| if (Arg) { |
| TemplateArgs.push_back(Arg); |
| TemplateArgIsType.push_back(IsType); |
| TemplateArgLocations.push_back(Loc); |
| } else { |
| SkipUntil(tok::comma, tok::greater, true, true); |
| return true; |
| } |
| |
| // If the next token is a comma, consume it and keep reading |
| // arguments. |
| if (Tok.isNot(tok::comma)) break; |
| |
| // Consume the comma. |
| ConsumeToken(); |
| } |
| |
| return Tok.isNot(tok::greater) && Tok.isNot(tok::greatergreater); |
| } |
| |
| /// \brief Parse a C++ explicit template instantiation |
| /// (C++ [temp.explicit]). |
| /// |
| /// explicit-instantiation: |
| /// 'template' declaration |
| Parser::DeclPtrTy |
| Parser::ParseExplicitInstantiation(SourceLocation TemplateLoc, |
| SourceLocation &DeclEnd) { |
| return ParseSingleDeclarationAfterTemplate(Declarator::FileContext, |
| ParsedTemplateInfo(TemplateLoc), |
| DeclEnd, AS_none); |
| } |
