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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_pod is_pod]
- template <class T>
- struct is_pod : public __tof {};
-
- __inherit If T is a (possibly cv-qualified) POD type then inherits from __true_type,
- otherwise inherits from __false_type.
- POD stands for "Plain old data".
- Arithmetic types, and enumeration types,
- a pointers and pointer to members are all PODs. Classes and unions can also
- be POD's if they have no non-static data members that are of reference or
- non-POD type, no user defined constructors, no user defined assignment
- operators, no private or protected non-static data members,
- no virtual functions and no base classes. Finally, a cv-qualified POD is
- still a POD, as is an array of PODs.
- __std_ref 3.9p10 and 9p4 (Note that POD's are also aggregates, see 8.5.1).
- __compat Without some (as yet unspecified) help from the compiler, is_pod will
- never report that a class or struct is a POD; this is always safe,
- if possibly sub-optimal.
- Currently (June 2015) compilers more recent than Visual C++ 8, Clang-3, GCC-4.3, Greenhills 6.0,
- Intel-11.0, and Codegear have the necessary compiler __intrinsics to ensure that this
- trait "just works". You may also test to see if the necessary __intrinsics are available
- by checking to see if the macro `BOOST_IS_POD` is defined.
- __header ` #include <boost/type_traits/is_pod.hpp>` or ` #include <boost/type_traits.hpp>`
- __examples
- [:`is_pod<int>` inherits from `__true_type`.]
- [:`is_pod<char*>::type` is the type `__true_type`.]
- [:`is_pod<int (*)(long)>::value` is an integral constant
- expression that evaluates to /true/.]
- [:`is_pod<MyClass>::value` is an integral constant
- expression that evaluates to /false/.]
- [:`is_pod<T>::value_type` is the type `bool`.]
- [endsect]
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