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
|
/*=========================================================================
Program: Insight Segmentation & Registration Toolkit
Module: itkTestFriendTemplatedFunction.cxx
Language: C++
Date: $Date$
Version: $Revision$
Copyright (c) Insight Software Consortium. All rights reserved.
See ITKCopyright.txt or http://www.itk.org/HTML/Copyright.htm for details.
This software is distributed WITHOUT ANY WARRANTY; without even
the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the above copyright notices for more information.
=========================================================================*/
/*
This file tests the syntax that the compiler supports for declaring
templated functions as friends of a templated class.
*/
//
// Here is our templated function, forward declared
//
template <class T> class WantToHaveFriend;
template <class T>
bool operator==( const WantToHaveFriend<T> & a, const WantToHaveFriend<T> & b );
//
// Here is our templated class
//
template <class T>
class WantToHaveFriend
{
public:
typedef WantToHaveFriend Self;
WantToHaveFriend()
{
x = 0;
}
void DoNothing() const
{
// of course... do nothing.
}
//
// Here are the variants that some compilers use
//
#ifdef TRY_COMPILE_FRIEND_WITH_NULL_TEMPLATE_STRING
friend bool operator==(const Self &, const Self &);
#endif
#ifdef TRY_COMPILE_FRIEND_WITH_EMPTY_TEMPLATE_BRACKETS
friend bool operator==<>(const Self &, const Self &);
#endif
#ifdef TRY_COMPILE_FRIEND_WITH_TEMPLATE_ARGUMENTS
friend bool operator==<Self>(const Self &, const Self &);
#endif
private:
int x;
};
template <class T>
bool operator==( const WantToHaveFriend<T> & a, const WantToHaveFriend<T> & b )
{ return a.x == b.x; }
int main()
{
typedef WantToHaveFriend<int> FriendlyType;
FriendlyType foo1;
FriendlyType foo2;
bool result = ( foo1 == foo2 );
if( result )
{
return 1;
}
return 0;
}
|
