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1[/
2 Copyright 2007 John Maddock.
3 Distributed under the Boost Software License, Version 1.0.
4 (See accompanying file LICENSE_1_0.txt or copy at
5 http://www.boost.org/LICENSE_1_0.txt).
6]
7
8[section:is_pointer is_pointer]
9 template <class T>
10 struct is_pointer : public __tof {};
11
12__inherit If T is a (possibly cv-qualified) pointer type (includes function pointers,
13but excludes pointers to members) then inherits from __true_type,
14otherwise inherits from __false_type.
15
16__std_ref 3.9.2p2 and 8.3.1.
17
18__header ` #include <boost/type_traits/is_pointer.hpp>` or ` #include <boost/type_traits.hpp>`
19
20[all_compilers]
21
22__examples
23
24[:`is_pointer<int*>` inherits from `__true_type`.]
25
26[:`is_pointer<char* const>::type` is the type `__true_type`.]
27
28[:`is_pointer<int (*)(long)>::value` is an integral constant
29expression that evaluates to /true/.]
30
31[:`is_pointer<int (MyClass::*)(long)>::value` is an integral constant
32expression that evaluates to /false/.]
33
34[:`is_pointer<int (MyClass::*)>::value` is an integral constant
35expression that evaluates to /false/.]
36
37[:`is_pointer<T>::value_type` is the type `bool`.]
38
39[important `is_pointer` detects "real" pointer types only, and /not/ smart pointers.
40Users should not specialise `is_pointer` for smart pointer types, as doing so may cause
41Boost (and other third party) code to fail to function correctly.
42Users wanting a trait to detect smart pointers should create their own.
43However, note that there is no way in general to auto-magically detect smart pointer types,
44so such a trait would have to be partially specialised for each supported smart pointer type.]
45
46[endsect]
47