DeclVisitor.h revision b219cfc4d75f0a03630b7c4509ef791b7e97b2c8 
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/DeclObjC.h"
18#include "clang/AST/DeclCXX.h"
19#include "clang/AST/DeclFriend.h"
20#include "clang/AST/DeclTemplate.h"
21
22namespace clang {
23
24#define DISPATCH(NAME, CLASS) \
25  return static_cast<ImplClass*>(this)-> Visit##NAME(static_cast<CLASS*>(D))
26
27/// \brief A simple visitor class that helps create declaration visitors.
28template<typename ImplClass, typename RetTy=void>
29class DeclVisitor {
30public:
31  RetTy Visit(Decl *D) {
32    switch (D->getKind()) {
33      default: llvm_unreachable("Decl that isn't part of DeclNodes.inc!");
34#define DECL(DERIVED, BASE) \
35      case Decl::DERIVED: DISPATCH(DERIVED##Decl, DERIVED##Decl);
36#define ABSTRACT_DECL(DECL)
37#include "clang/AST/DeclNodes.inc"
38    }
39  }
40
41  // If the implementation chooses not to implement a certain visit
42  // method, fall back to the parent.
43#define DECL(DERIVED, BASE) \
44  RetTy Visit##DERIVED##Decl(DERIVED##Decl *D) { DISPATCH(BASE, BASE); }
45#include "clang/AST/DeclNodes.inc"
46
47  RetTy VisitDecl(Decl *D) { return RetTy(); }
48};
49
50#undef DISPATCH
51
52}  // end namespace clang
53
54#endif // LLVM_CLANG_AST_DECLVISITOR_H
55