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
15namespace clang {
16namespace diff {
17
18using DynTypedNode = DynTypedNode;
19
20/// Within a tree, this identifies a node by its preorder offset.
21struct NodeId {
22private:
23  static constexpr int InvalidNodeId = -1;
24
25public:
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