1 //===--- DeclVisitor.h - Visitor for Decl subclasses ------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the DeclVisitor interface. 11 // 12 //===----------------------------------------------------------------------===// 13 #ifndef LLVM_CLANG_AST_DECLVISITOR_H 14 #define LLVM_CLANG_AST_DECLVISITOR_H 15 16 #include "clang/AST/Decl.h" 17 #include "clang/AST/DeclCXX.h" 18 #include "clang/AST/DeclFriend.h" 19 #include "clang/AST/DeclObjC.h" 20 #include "clang/AST/DeclOpenMP.h" 21 #include "clang/AST/DeclTemplate.h" 22 23 namespace clang { 24 namespace declvisitor { 25 26 template <typename T> struct make_ptr { typedef T *type; }; 27 template <typename T> struct make_const_ptr { typedef const T *type; }; 28 29 /// \brief A simple visitor class that helps create declaration visitors. 30 template<template <typename> class Ptr, typename ImplClass, typename RetTy=void> 31 class Base { 32 public: 33 34 #define PTR(CLASS) typename Ptr<CLASS>::type 35 #define DISPATCH(NAME, CLASS) \ 36 return static_cast<ImplClass*>(this)->Visit##NAME(static_cast<PTR(CLASS)>(D)) 37 Visit(PTR (Decl)D)38 RetTy Visit(PTR(Decl) D) { 39 switch (D->getKind()) { 40 #define DECL(DERIVED, BASE) \ 41 case Decl::DERIVED: DISPATCH(DERIVED##Decl, DERIVED##Decl); 42 #define ABSTRACT_DECL(DECL) 43 #include "clang/AST/DeclNodes.inc" 44 } 45 llvm_unreachable("Decl that isn't part of DeclNodes.inc!"); 46 } 47 48 // If the implementation chooses not to implement a certain visit 49 // method, fall back to the parent. 50 #define DECL(DERIVED, BASE) \ 51 RetTy Visit##DERIVED##Decl(PTR(DERIVED##Decl) D) { DISPATCH(BASE, BASE); } 52 #include "clang/AST/DeclNodes.inc" 53 VisitDecl(PTR (Decl)D)54 RetTy VisitDecl(PTR(Decl) D) { return RetTy(); } 55 56 #undef PTR 57 #undef DISPATCH 58 }; 59 60 } // end namespace declvisitor 61 62 /// \brief A simple visitor class that helps create declaration visitors. 63 /// 64 /// This class does not preserve constness of Decl pointers (see also 65 /// ConstDeclVisitor). 66 template<typename ImplClass, typename RetTy=void> 67 class DeclVisitor 68 : public declvisitor::Base<declvisitor::make_ptr, ImplClass, RetTy> {}; 69 70 /// \brief A simple visitor class that helps create declaration visitors. 71 /// 72 /// This class preserves constness of Decl pointers (see also DeclVisitor). 73 template<typename ImplClass, typename RetTy=void> 74 class ConstDeclVisitor 75 : public declvisitor::Base<declvisitor::make_const_ptr, ImplClass, RetTy> {}; 76 77 } // end namespace clang 78 79 #endif // LLVM_CLANG_AST_DECLVISITOR_H 80