Generic.h

   1 /*
   2  * Copyright (c) 2003 Robert Collins.
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     A copy of the GNU General Public License can be found at
  10  *     http://www.gnu.org/
  11  *
  12  * Written by Robert Collins <robertc@hotmail.com>
  13  *
  14  */
  15
  16 #ifndef SETUP_GENERIC_H
  17 #define SETUP_GENERIC_H
  18
  19 /* Todo fully paramterise */
  20 template <class _Visitor, class _Predicate>
  21 struct _visit_if {
  22   _visit_if(_Visitor v, _Predicate p) : visitor(v), predicate (p) {}
  23   void operator() (typename _Visitor::argument_type& arg) {
  24     if (predicate(arg))
  25       visitor(arg);
  26   }
  27   _Visitor visitor;
  28   _Predicate predicate;
  29 };
  30
  31 template <class _Visitor, class _Predicate>
  32 _visit_if<_Visitor, _Predicate>
  33 visit_if(_Visitor visitor, _Predicate predicate)
  34 {
  35   return _visit_if<_Visitor, _Predicate>(visitor, predicate);
  36 }
  37
  38 #endif /* SETUP_GENERIC_H */