1 //===- ASTDiffInternal.h --------------------------------------*- C++ -*- -===//
2 //
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef LLVM_CLANG_TOOLING_ASTDIFF_ASTDIFFINTERNAL_H
11 #define LLVM_CLANG_TOOLING_ASTDIFF_ASTDIFFINTERNAL_H
12 
13 #include "clang/AST/ASTTypeTraits.h"
14 
15 namespace clang {
16 namespace diff {
17 
18 using DynTypedNode = DynTypedNode;
19 
20 /// Within a tree, this identifies a node by its preorder offset.
21 struct NodeId {
22 private:
23   static constexpr int InvalidNodeId = -1;
24 
25 public:
26   int Id;
27 
28   NodeId() : Id(InvalidNodeId) {}
29   NodeId(int Id) : Id(Id) {}
30 
31   operator int() const { return Id; }
32   NodeId &operator++() { return ++Id, *this; }
33   NodeId &operator--() { return --Id, *this; }
34   // Support defining iterators on NodeId.
35   NodeId &operator*() { return *this; }
36 
37   bool isValid() const { return Id != InvalidNodeId; }
38   bool isInvalid() const { return Id == InvalidNodeId; }
39 };
40 
41 } // end namespace diff
42 } // end namespace clang
43 #endif
44