Dogcows Code - chaz/yoink/blob - src/moof/cml/core/meta/if.h

   1 /* -*- C++ -*- ------------------------------------------------------------
   2
   3 Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
   4
   5 The Configurable Math Library (CML) is distributed under the terms of the
   6 Boost Software License, v1.0 (see cml/LICENSE for details).
   7
   8  *-----------------------------------------------------------------------*/
   9 /** @file
  10  *  @brief
  11  */
  12
  13 #ifndef meta_if_h
  14 #define meta_if_h
  15
  16 #include <cml/core/meta/common.h>
  17
  18 namespace cml {
  19
  20 /** Select argument type based upon truth value. */
  21 template<bool yn, typename TrueT, typename FalseT> struct select_if;
  22
  23 /** Result is TrueT if true. */
  24 template<typename TrueT, typename FalseT>
  25 struct select_if<true,TrueT,FalseT> {
  26     typedef TrueT result;
  27     enum { is_true = true };
  28 };
  29
  30 /** Result is FalseT if false. */
  31 template<typename TrueT, typename FalseT>
  32 struct select_if<false,TrueT,FalseT> {
  33     typedef FalseT result;
  34     enum { is_true = false };
  35 };
  36
  37 } // namespace cml
  38
  39 #endif
  40
  41 // -------------------------------------------------------------------------
  42 // vim:ft=cpp