summaryrefslogtreecommitdiff
path: root/2005/i/robert/src/utils/callback.hh
blob: c5dc2291eddaffccaa3f0a8e12fe46dbfcf5f3c8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
#ifndef callback_hh
#define callback_hh
// callback.hh
// robert - programme du robot 2005. {{{
//
// Copyright (C) 2004 Nicolas Schodet
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// Contact :
//        Web: http://perso.efrei.fr/~schodet/
//      Email: <contact@ni.fr.eu.org>
// }}}

#include <stdexcept>

/// Class to store a callback.  This callback can be of any type (function or
/// fonctor).
template<typename R>
class Callback
{
    class AbstractHolder;
    AbstractHolder *holder_;
  public:
    /// Return value.
    typedef R result_type;
  public:
    /// Default constructor.  Make an empty callback.
    Callback (void);
    /// Constructor.
    template<typename T>
    Callback (T callback);
    /// Copy constructor.
    Callback (const Callback &other);
    /// Destructor.
    ~Callback (void);
    /// Assignement operator.
    Callback &operator= (const Callback &rhs);
    /// Call the contained callback.
    R operator () (void);
    /// Swap the callback content with another callback.
    void swap (Callback &rhs);
    /// Change the contained callback.
    template<typename T>
    Callback &operator= (T rhs);
    /// Test if empty.
    bool empty (void) const;
    /// Test if not empty.
    operator bool (void) const;
  private:
    /// Abstract container.
    class AbstractHolder
      {
      public:
	virtual ~AbstractHolder (void);
	virtual R operator () (void) = 0;
	virtual AbstractHolder *clone (void) = 0;
      };
    /// Templated container.
    template<typename T>
    class Holder : public AbstractHolder
      {
      private:
	T callback_;
      public:
	Holder (T callback);
	virtual R operator () (void);
	virtual AbstractHolder *clone (void);
      };
};

/// Exception thrown on call of an empty callback.
class bad_callback : public std::runtime_error
{
  public:
    bad_callback (void) : std::runtime_error ("bad_callback: empty callback call")
      {
      }
};

#include "callback.tcc"

#endif // callback_hh