FilteredNodeIterator.h (1334B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ 2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */ 3 /* This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 /** 8 * Implementation of a generic filtered iterator over nodes. 9 */ 10 11 #ifndef mozilla_dom_FilteredNodeIterator_h 12 #define mozilla_dom_FilteredNodeIterator_h 13 14 #include "nsINode.h" 15 16 namespace mozilla::dom { 17 18 template <typename T, typename Iter> 19 class FilteredNodeIterator : public Iter { 20 public: 21 explicit FilteredNodeIterator(const nsINode& aNode) : Iter(aNode) { 22 EnsureValid(); 23 } 24 25 FilteredNodeIterator& begin() { return *this; } 26 using Iter::end; 27 28 void operator++() { 29 Iter::operator++(); 30 EnsureValid(); 31 } 32 33 using Iter::operator!=; 34 35 T* operator*() { 36 nsINode* node = Iter::operator*(); 37 MOZ_ASSERT(!node || T::FromNode(node)); 38 return static_cast<T*>(node); 39 } 40 41 private: 42 void EnsureValid() { 43 while (true) { 44 nsINode* node = Iter::operator*(); 45 if (!node || T::FromNode(node)) { 46 return; 47 } 48 Iter::operator++(); 49 } 50 } 51 52 FilteredNodeIterator() : Iter() {} 53 }; 54 55 } // namespace mozilla::dom 56 57 #endif // mozilla_dom_FilteredNodeIterator.h