| /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| /* vim: set ts=8 sts=2 et sw=2 tw=80: */ |
| /* This Source Code Form is subject to the terms of the Mozilla Public |
| * License, v. 2.0. If a copy of the MPL was not distributed with this |
| * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| |
| /* An opaque integral type supporting only comparison operators. */ |
| |
| #ifndef mozilla_Opaque_h |
| #define mozilla_Opaque_h |
| |
| #include "mozilla/TypeTraits.h" |
| |
| namespace mozilla { |
| |
| /** |
| * Opaque<T> is a replacement for integral T in cases where only comparisons |
| * must be supported, and it's desirable to prevent accidental dependency on |
| * exact values. |
| */ |
| template<typename T> |
| class Opaque final |
| { |
| static_assert(mozilla::IsIntegral<T>::value, |
| "mozilla::Opaque only supports integral types"); |
| |
| T mValue; |
| |
| public: |
| Opaque() {} |
| explicit Opaque(T aValue) : mValue(aValue) {} |
| |
| bool operator==(const Opaque& aOther) const { |
| return mValue == aOther.mValue; |
| } |
| |
| bool operator!=(const Opaque& aOther) const { |
| return !(*this == aOther); |
| } |
| }; |
| |
| } // namespace mozilla |
| |
| #endif /* mozilla_Opaque_h */ |
