1 //===- DeclVisitor.h - Visitor for Decl subclasses --------------*- C++ -*-===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file defines the DeclVisitor interface.
11 //===----------------------------------------------------------------------===//
13 #ifndef LLVM_CLANG_AST_DECLVISITOR_H
14 #define LLVM_CLANG_AST_DECLVISITOR_H
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/DeclBase.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclFriend.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/AST/DeclOpenMP.h"
22 #include "clang/AST/DeclTemplate.h"
23 #include "llvm/ADT/STLExtras.h"
24 #include "llvm/Support/ErrorHandling.h"
28 namespace declvisitor {
29 /// A simple visitor class that helps create declaration visitors.
30 template<template <typename> class Ptr, typename ImplClass, typename RetTy=void>
33 #define PTR(CLASS) typename Ptr<CLASS>::type
34 #define DISPATCH(NAME, CLASS) \
35 return static_cast<ImplClass*>(this)->Visit##NAME(static_cast<PTR(CLASS)>(D))
37 RetTy Visit(PTR(Decl) D) {
38 switch (D->getKind()) {
39 #define DECL(DERIVED, BASE) \
40 case Decl::DERIVED: DISPATCH(DERIVED##Decl, DERIVED##Decl);
41 #define ABSTRACT_DECL(DECL)
42 #include "clang/AST/DeclNodes.inc"
44 llvm_unreachable("Decl that isn't part of DeclNodes.inc!");
47 // If the implementation chooses not to implement a certain visit
48 // method, fall back to the parent.
49 #define DECL(DERIVED, BASE) \
50 RetTy Visit##DERIVED##Decl(PTR(DERIVED##Decl) D) { DISPATCH(BASE, BASE); }
51 #include "clang/AST/DeclNodes.inc"
53 RetTy VisitDecl(PTR(Decl) D) { return RetTy(); }
59 } // namespace declvisitor
61 /// A simple visitor class that helps create declaration visitors.
63 /// This class does not preserve constness of Decl pointers (see also
64 /// ConstDeclVisitor).
65 template <typename ImplClass, typename RetTy = void>
67 : public declvisitor::Base<std::add_pointer, ImplClass, RetTy> {};
69 /// A simple visitor class that helps create declaration visitors.
71 /// This class preserves constness of Decl pointers (see also DeclVisitor).
72 template <typename ImplClass, typename RetTy = void>
73 class ConstDeclVisitor
74 : public declvisitor::Base<llvm::make_const_ptr, ImplClass, RetTy> {};
78 #endif // LLVM_CLANG_AST_DECLVISITOR_H