Orocos Real-Time Toolkit  2.9.0
NA.hpp
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1 /***************************************************************************
2  tag: FMTC do nov 2 13:05:59 CET 2006 NA.hpp
3 
4  NA.hpp - description
5  -------------------
6  begin : do november 02 2006
7  copyright : (C) 2006 FMTC
8  email : peter.soetens@fmtc.be
9 
10  ***************************************************************************
11  * This library is free software; you can redistribute it and/or *
12  * modify it under the terms of the GNU General Public *
13  * License as published by the Free Software Foundation; *
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15  * *
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17  * software library without restriction. Specifically, if other files *
18  * instantiate templates or use macros or inline functions from this *
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36  ***************************************************************************/
37 
38 
39 #ifndef ORO_NA_HPP
40 #define ORO_NA_HPP
41 
42 #include <boost/type_traits.hpp>
43 
44 namespace RTT
45 {
46  namespace internal
47  {
52  template<class T>
53  struct NA
54  {
55  public:
56  typedef typename boost::remove_const<typename boost::remove_reference<T>::type>::type value_type;
57  static T na() { return Gna; }
58  private:
59  static value_type Gna;
60  };
61 
65  template<>
66  struct NA<void>
67  {
68  typedef void value_type;
69  static void na() {};
70  };
71 
72  template<class T>
74  }
75 }
76 #endif
static T na()
Definition: NA.hpp:57
This class is used to return a &#39;default&#39; value when no value is available (&#39;Not Available&#39;).
Definition: NA.hpp:53
boost::remove_const< typename boost::remove_reference< T >::type >::type value_type
Definition: NA.hpp:56
Contains TaskContext, Activity, OperationCaller, Operation, Property, InputPort, OutputPort, Attribute.
Definition: Activity.cpp:52
static void na()
Definition: NA.hpp:69