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### has_trivial_move_assign

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

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

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

Compiler Compatibility: Without some (as yet unspecified) help from the compiler, has_trivial_move_assign will never report that a user-defined class or struct has a trivial move assign; this is always safe, if possibly sub-optimal. In addition, in order to correctly handle private or deleted move assignment operators then c++11's `decltype` is required. 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_ASSIGN` is defined.

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

Examples:

> `has_trivial_move_assign<int>` inherits from `true_type`.

> `has_trivial_move_assign<char*>::type` is the type `true_type`.

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

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

> `has_trivial_move_assign<T>::value_type` is the type `bool`.