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  1. // TR2 <ratio> -*- C++ -*-
  2. // Copyright (C) 2010-2020 Free Software Foundation, Inc.
  3. //
  4. // This file is part of the GNU ISO C++ Library. This library is free
  5. // software; you can redistribute it and/or modify it under the
  6. // terms of the GNU General Public License as published by the
  7. // Free Software Foundation; either version 3, or (at your option)
  8. // any later version.
  9. // This library is distributed in the hope that it will be useful,
  10. // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12. // GNU General Public License for more details.
  13. // Under Section 7 of GPL version 3, you are granted additional
  14. // permissions described in the GCC Runtime Library Exception, version
  15. // 3.1, as published by the Free Software Foundation.
  16. // You should have received a copy of the GNU General Public License and
  17. // a copy of the GCC Runtime Library Exception along with this program;
  18. // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
  19. // <http://www.gnu.org/licenses/>.
  20. /** @file tr2/ratio
  21. * This is a TR2 C++ Library header.
  22. */
  23. #include <ratio>
  24. namespace std _GLIBCXX_VISIBILITY(default)
  25. {
  26. _GLIBCXX_BEGIN_NAMESPACE_VERSION
  27. namespace tr2
  28. {
  29. template<intmax_t _Pn, size_t _Bit,
  30. bool = _Bit < static_cast<size_t>
  31. (std::numeric_limits<intmax_t>::digits)>
  32. struct __safe_lshift
  33. { static const intmax_t __value = 0; };
  34. template<intmax_t _Pn, size_t _Bit>
  35. struct __safe_lshift<_Pn, _Bit, true>
  36. { static const intmax_t __value = _Pn << _Bit; };
  37. /// Add binary prefixes (IEC 60027-2 A.2 and ISO/IEC 80000).
  38. typedef ratio<__safe_lshift<1, 10>::__value, 1> kibi;
  39. typedef ratio<__safe_lshift<1, 20>::__value, 1> mebi;
  40. typedef ratio<__safe_lshift<1, 30>::__value, 1> gibi;
  41. typedef ratio<__safe_lshift<1, 40>::__value, 1> tebi;
  42. typedef ratio<__safe_lshift<1, 50>::__value, 1> pebi;
  43. typedef ratio<__safe_lshift<1, 60>::__value, 1> exbi;
  44. //typedef ratio<__safe_lshift<1, 70>::__value, 1> zebi;
  45. //typedef ratio<__safe_lshift<1, 80>::__value, 1> yobi;
  46. }
  47. _GLIBCXX_END_NAMESPACE_VERSION
  48. }