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template <class T>
struct has_trivial_move_constructor : public true_type-or-false_type {};

Inherits: If T is a (possibly cv-qualified) type with a trivial move-constructor then inherits from true_type, otherwise inherits from false_type.

If a type has a trivial move-constructor then the constructor has the same effect as copying the bits of one object to the other: calls to the constructor can be safely replaced with a call to memcpy.

Compiler Compatibility: Without some (as yet unspecified) help from the compiler, has_trivial_move_constructor will never report that a user-defined class or struct has a trivial constructor; this is always safe, if possibly sub-optimal. In addition C++11's decltype is required to correctly support deleted or private move constructors. Currently (June 2015) compilers that have the necessary intrinsics to ensure that this trait "just works" include Clang, GCC-5.1, and MSVC-12.0. You may also test to see if the necessary intrinsics are available by checking to see if the macro BOOST_HAS_TRIVIAL_MOVE_CONSTRUCTOR is defined.

Header: #include <boost/type_traits/has_trivial_move_constructor.hpp> or #include <boost/type_traits.hpp>


has_trivial_move_constructor<int> inherits from true_type.

has_trivial_move_constructor<char*>::type is the type true_type.

has_trivial_move_constructor<int (*)(long)>::value is an integral constant expression that evaluates to true.

has_trivial_move_constructor<MyClass>::value is an integral constant expression that evaluates to false.

has_trivial_move_constructor<T>::value_type is the type bool.