有一条规则说明std :: tuple的成员被破坏了吗?
例如,如果Function1返回一个std::tuple<std::unique_ptr<ClassA>, std::unique_ptr<ClassB>>to Function2,那么我可以确定(当Function2剩下的范围时)ClassB第二个成员ClassA引用的实例在第一个成员引用的实例之前被销毁吗?
std::tuple< std::unique_ptr< ClassA >, std::unique_ptr< ClassB > > Function1()
{
std::tuple< std::unique_ptr< ClassA >, std::unique_ptr< ClassB > > garbage;
get<0>(garbage).reset( /* ... */ );
get<1>(garbage).reset( /* ... */ );
return garbage;
}
void Function2()
{
auto to_be_destroyed = Function1();
// ... do something else
// to_be_destroyed leaves scope
// Is the instance of ClassB destroyed before the instance of ClassA?
}
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