mfbt/NumericLimits.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 /* Compatibility with std::numeric_limits<char16_t>. */
   8
   9 #ifndef mozilla_NumericLimits_h
  10 #define mozilla_NumericLimits_h
  11
  12 #include "mozilla/Char16.h"
  13
  14 #include <limits>
  15 #include <stdint.h>
  16
  17 namespace mozilla {
  18
  19 /**
  20  * The NumericLimits class provides a compatibility layer with std::numeric_limits
  21  * for char16_t, otherwise it is exactly the same as std::numeric_limits.
  22  * Code which does not need std::numeric_limits<char16_t> should avoid using
  23  * NumericLimits.
  24  */
  25 template<typename T>
  26 class NumericLimits : public std::numeric_limits<T>
  27 {
  28 };
  29
  30 #ifdef MOZ_CHAR16_IS_NOT_WCHAR
  31 template<>
  32 class NumericLimits<char16_t> : public std::numeric_limits<uint16_t>
  33 {
  34   // char16_t and uint16_t numeric limits should be exactly the same.
  35 };
  36 #endif
  37
  38 } // namespace mozilla
  39
  40 #endif /* mozilla_NumericLimits_h */