mfbt/Literals.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 /* Helpers for units on integer literals. */
   8
   9 #ifndef mozilla_Literals_h
  10 #define mozilla_Literals_h
  11
  12 #include <cstddef>
  13
  14 // User-defined literals to make constants more legible.  Use them by
  15 // appending them to literals such as:
  16 //
  17 // size_t page_size = 4_KiB;
  18 //
  19 constexpr size_t operator"" _KiB(unsigned long long int aNum) {
  20   return size_t(aNum) * 1024;
  21 }
  22
  23 constexpr size_t operator"" _KiB(long double aNum) {
  24   return size_t(aNum * 1024);
  25 }
  26
  27 constexpr size_t operator"" _MiB(unsigned long long int aNum) {
  28   return size_t(aNum) * 1024_KiB;
  29 }
  30
  31 constexpr size_t operator"" _MiB(long double aNum) {
  32   return size_t(aNum * 1024_KiB);
  33 }
  34
  35 constexpr double operator""_percent(long double aPercent) {
  36   return double(aPercent) / 100;
  37 }
  38
  39 #endif /* ! mozilla_Literals_h */