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- [/
- Copyright 2007 John Maddock.
- Distributed under the Boost Software License, Version 1.0.
- (See accompanying file LICENSE_1_0.txt or copy at
- http://www.boost.org/LICENSE_1_0.txt).
- ]
- [section:is_pointer is_pointer]
- template <class T>
- struct is_pointer : public __tof {};
-
- __inherit If T is a (possibly cv-qualified) pointer type (includes function pointers,
- but excludes pointers to members) then inherits from __true_type,
- otherwise inherits from __false_type.
- __std_ref 3.9.2p2 and 8.3.1.
- __header ` #include <boost/type_traits/is_pointer.hpp>` or ` #include <boost/type_traits.hpp>`
- [all_compilers]
- __examples
- [:`is_pointer<int*>` inherits from `__true_type`.]
- [:`is_pointer<char* const>::type` is the type `__true_type`.]
- [:`is_pointer<int (*)(long)>::value` is an integral constant
- expression that evaluates to /true/.]
- [:`is_pointer<int (MyClass::*)(long)>::value` is an integral constant
- expression that evaluates to /false/.]
- [:`is_pointer<int (MyClass::*)>::value` is an integral constant
- expression that evaluates to /false/.]
- [:`is_pointer<T>::value_type` is the type `bool`.]
- [important `is_pointer` detects "real" pointer types only, and /not/ smart pointers.
- Users should not specialise `is_pointer` for smart pointer types, as doing so may cause
- Boost (and other third party) code to fail to function correctly.
- Users wanting a trait to detect smart pointers should create their own.
- However, note that there is no way in general to auto-magically detect smart pointer types,
- so such a trait would have to be partially specialised for each supported smart pointer type.]
- [endsect]
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