...one of the most highly
regarded and expertly designed C++ library projects in the
world. — Herb Sutter and Andrei
template <class T> struct has_trivial_move_assign : public
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
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
has_trivial_move_assign<char*>::typeis the type
has_trivial_move_assign<int (*)(long)>::valueis an integral constant expression that evaluates to true.
has_trivial_move_assign<MyClass>::valueis an integral constant expression that evaluates to false.
has_trivial_move_assign<T>::value_typeis the type