clang  8.0.0svn
DeclVisitor.h
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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 
14 #ifndef LLVM_CLANG_AST_DECLVISITOR_H
15 #define LLVM_CLANG_AST_DECLVISITOR_H
16 
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclBase.h"
19 #include "clang/AST/DeclCXX.h"
20 #include "clang/AST/DeclFriend.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/DeclOpenMP.h"
23 #include "clang/AST/DeclTemplate.h"
24 #include "llvm/ADT/STLExtras.h"
25 #include "llvm/Support/ErrorHandling.h"
26 
27 namespace clang {
28 
29 namespace declvisitor {
30 /// A simple visitor class that helps create declaration visitors.
31 template<template <typename> class Ptr, typename ImplClass, typename RetTy=void>
32 class Base {
33 public:
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 
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 
54  RetTy VisitDecl(PTR(Decl) D) { return RetTy(); }
55 
56 #undef PTR
57 #undef DISPATCH
58 };
59 
60 } // namespace declvisitor
61 
62 /// 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>
68  : public declvisitor::Base<std::add_pointer, ImplClass, RetTy> {};
69 
70 /// 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>
75  : public declvisitor::Base<llvm::make_const_ptr, ImplClass, RetTy> {};
76 
77 } // namespace clang
78 
79 #endif // LLVM_CLANG_AST_DECLVISITOR_H
#define PTR(CLASS)
Definition: DeclVisitor.h:34
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:87
Defines the C++ template declaration subclasses.
A simple visitor class that helps create declaration visitors.
Definition: DeclVisitor.h:32
This file defines OpenMP nodes for declarative directives.
A simple visitor class that helps create declaration visitors.
Definition: DeclVisitor.h:67
Dataflow Directional Tag Classes.
Kind getKind() const
Definition: DeclBase.h:421
RetTy Visit(PTR(Decl) D)
Definition: DeclVisitor.h:38
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
RetTy VisitDecl(PTR(Decl) D)
Definition: DeclVisitor.h:54
A simple visitor class that helps create declaration visitors.
Definition: DeclVisitor.h:74