[/ Copyright 2007 John Maddock. Copyright 2013 Antony Polukhin. 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:has_trivial_move_assign has_trivial_move_assign] template struct has_trivial_move_assign : public __tof {}; __inherit 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`. __compat 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 ` or ` #include ` __examples [:`has_trivial_move_assign` inherits from `__true_type`.] [:`has_trivial_move_assign::type` is the type `__true_type`.] [:`has_trivial_move_assign::value` is an integral constant expression that evaluates to /true/.] [:`has_trivial_move_assign::value` is an integral constant expression that evaluates to /false/.] [:`has_trivial_move_assign::value_type` is the type `bool`.] [endsect]