dom/bindings/Record.h

   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  * Class for representing record arguments.  Basically an array under the hood.
   9  */
  10
  11 #ifndef mozilla_dom_Record_h
  12 #define mozilla_dom_Record_h
  13
  14 #include <utility>
  15
  16 #include "mozilla/Attributes.h"
  17 #include "nsHashKeys.h"
  18 #include "nsString.h"
  19 #include "nsTArray.h"
  20 #include "nsTHashtable.h"
  21
  22 namespace mozilla::dom {
  23
  24 namespace binding_detail {
  25 template <typename KeyType, typename ValueType>
  26 class RecordEntry {
  27  public:
  28   RecordEntry() = default;
  29
  30   // Move constructor so we can do Records of Records.
  31   RecordEntry(RecordEntry<KeyType, ValueType>&& aOther)
  32       : mKey(std::move(aOther.mKey)), mValue(std::move(aOther.mValue)) {}
  33
  34   KeyType mKey;
  35   ValueType mValue;
  36 };
  37
  38 // Specialize for a JSObject* ValueType and initialize it on construction, so we
  39 // don't need to worry about un-initialized JSObject* floating around.
  40 template <typename KeyType>
  41 class RecordEntry<KeyType, JSObject*> {
  42  public:
  43   RecordEntry() : mValue(nullptr) {}
  44
  45   // Move constructor so we can do Records of Records.
  46   RecordEntry(RecordEntry<KeyType, JSObject*>&& aOther)
  47       : mKey(std::move(aOther.mKey)), mValue(std::move(aOther.mValue)) {}
  48
  49   KeyType mKey;
  50   JSObject* mValue;
  51 };
  52
  53 }  // namespace binding_detail
  54
  55 template <typename KeyType, typename ValueType>
  56 class Record {
  57  public:
  58   typedef typename binding_detail::RecordEntry<KeyType, ValueType> EntryType;
  59   typedef Record<KeyType, ValueType> SelfType;
  60
  61   Record() = default;
  62
  63   // Move constructor so we can do Record of Record.
  64   Record(SelfType&& aOther) : mEntries(std::move(aOther.mEntries)) {}
  65
  66   const nsTArray<EntryType>& Entries() const { return mEntries; }
  67
  68   nsTArray<EntryType>& Entries() { return mEntries; }
  69
  70  private:
  71   nsTArray<EntryType> mEntries;
  72 };
  73
  74 }  // namespace mozilla::dom
  75
  76 template <typename K, typename V>
  77 class nsDefaultComparator<mozilla::dom::binding_detail::RecordEntry<K, V>, K> {
  78  public:
  79   bool Equals(const mozilla::dom::binding_detail::RecordEntry<K, V>& aEntry,
  80               const K& aKey) const {
  81     return aEntry.mKey == aKey;
  82   }
  83 };
  84
  85 #endif  // mozilla_dom_Record_h