dom/smil/SMILNullType.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 #ifndef DOM_SMIL_SMILNULLTYPE_H_
   8 #define DOM_SMIL_SMILNULLTYPE_H_
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/SMILType.h"
  12
  13 namespace mozilla {
  14
  15 class SMILNullType : public SMILType {
  16  public:
  17   // Singleton for SMILValue objects to hold onto.
  18   static SMILNullType* Singleton();
  19
  20  protected:
  21   // SMILType Methods
  22   // -------------------
  23   void Init(SMILValue& aValue) const override {}
  24   void Destroy(SMILValue& aValue) const override {}
  25   nsresult Assign(SMILValue& aDest, const SMILValue& aSrc) const override;
  26
  27   // The remaining methods should never be called, so although they're very
  28   // simple they don't need to be inline.
  29   bool IsEqual(const SMILValue& aLeft, const SMILValue& aRight) const override;
  30   nsresult Add(SMILValue& aDest, const SMILValue& aValueToAdd,
  31                uint32_t aCount) const override;
  32   nsresult ComputeDistance(const SMILValue& aFrom, const SMILValue& aTo,
  33                            double& aDistance) const override;
  34   nsresult Interpolate(const SMILValue& aStartVal, const SMILValue& aEndVal,
  35                        double aUnitDistance, SMILValue& aResult) const override;
  36
  37  private:
  38   // Private constructor: prevent instances beyond my singleton.
  39   constexpr SMILNullType() = default;
  40 };
  41
  42 }  // namespace mozilla
  43
  44 #endif  // DOM_SMIL_SMILNULLTYPE_H_