[/ 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:has_trivial_assign has_trivial_assign] template struct has_trivial_assign : public __tof {}; __inherit If T is a (possibly cv-qualified) type with a trivial assignment-operator then inherits from __true_type, otherwise inherits from __false_type. If a type has a trivial 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_assign will never report that a user-defined class or struct has a trivial constructor; this is always safe, if possibly sub-optimal. In order to correctly handle deleted or private assignment operators, the compiler must also support C++11's `decltype`. Currently (May 2015) compilers more recent than Visual C++ 8, 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_HAS_TRIVIAL_ASSIGN` is defined. __std_ref 12.8p11. __header ` #include ` or ` #include ` __examples [:`has_trivial_assign` inherits from `__true_type`.] [:`has_trivial_assign::type` is the type `__true_type`.] [:`has_trivial_assign::value` is an integral constant expression that evaluates to /true/.] [:`has_trivial_assign::value` is an integral constant expression that evaluates to /false/.] [:`has_trivial_assign::value_type` is the type `bool`.] [endsect]