Method with_alias

tests/test_class_sh_factory_constructors.cpp:61–61

Some compilers complain about implicitly defined versions of some of the following:

    virtual ~with_alias() = default;
    // Some compilers complain about implicitly defined versions of some of the following:
    with_alias() = default;
    with_alias(const with_alias &) = default;
    with_alias(with_alias &&) = default;
    with_alias &operator=(const with_alias &) = default;