Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost
C++ Libraries
...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
template <class T>
struct is_stateless : public true_type-or-false_type {};
Inherits: If T is a stateless type then inherits from true_type, otherwise from false_type.
Type T must be a complete type.
A stateless type is a type that has no storage and whose constructors and
destructors are trivial. That means that is_stateless
only inherits from true_type
if the following expression is true:
::boost::has_trivial_constructor<T>::value && ::boost::has_trivial_copy<T>::value && ::boost::has_trivial_destructor<T>::value && ::boost::is_class<T>::value && ::boost::is_empty<T>::value
C++ Standard Reference: 3.9p10.
Header: #include
<boost/type_traits/is_stateless.hpp>
or #include <boost/type_traits.hpp>
Compiler Compatibility: Without some (as yet unspecified) help from the compiler, is_stateless will never report that a class or struct is stateless; this is always safe, if possibly sub-optimal. Currently (June 2015) compilers more recent than Visual C++ 8, Clang, GCC-4.3, Greenhills 6.0, Intel-11.0, and Codegear have the necessary compiler intrinsics to ensure that this trait "just works".