headers/private/kernel/util/KernelUtilsOrder.h

   1 // KernelUtilsOrders.h
   2 //
   3 // Copyright (c) 2003, Ingo Weinhold (bonefish@cs.tu-berlin.de)
   4 //
   5 // Permission is hereby granted, free of charge, to any person obtaining a
   6 // copy of this software and associated documentation files (the "Software"),
   7 // to deal in the Software without restriction, including without limitation
   8 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
   9 // and/or sell copies of the Software, and to permit persons to whom the
  10 // Software is furnished to do so, subject to the following conditions:
  11 //
  12 // The above copyright notice and this permission notice shall be included in
  13 // all copies or substantial portions of the Software.
  14 //
  15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  18 // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21 // DEALINGS IN THE SOFTWARE.
  22 //
  23 // Except as contained in this notice, the name of a copyright holder shall
  24 // not be used in advertising or otherwise to promote the sale, use or other
  25 // dealings in this Software without prior written authorization of the
  26 // copyright holder.
  27
  28 #ifndef _KERNEL_UTILS_ORDERS_H
  29 #define _KERNEL_UTILS_ORDERS_H
  30
  31 namespace KernelUtilsOrder {
  32
  33 // Ascending
  34 /*!     \brief A compare function object implying and ascending order.
  35
  36         The < operator must be defined on the template argument type.
  37 */
  38 template<typename Value>
  39 class Ascending {
  40 public:
  41         inline int operator()(const Value &a, const Value &b) const
  42         {
  43                 if (a < b)
  44                         return -1;
  45                 else if (b < a)
  46                         return 1;
  47                 return 0;
  48         }
  49 };
  50
  51 // Descending
  52 /*!     \brief A compare function object implying and descending order.
  53
  54         The < operator must be defined on the template argument type.
  55 */
  56 template<typename Value>
  57 class Descending {
  58 public:
  59         inline int operator()(const Value &a, const Value &b) const
  60         {
  61                 if (a < b)
  62                         return -1;
  63                 else if (b < a)
  64                         return 1;
  65                 return 0;
  66         }
  67 };
  68
  69 }       // namespace KernelUtilsOrder
  70
  71 #endif  // _KERNEL_UTILS_ORDERS_H