Operators aren't exposed for deepter-than-1-stage inheritance

[muffgaga]

namespace detail {
template<typename Derived, typename T>
struct BaseType
{
    // comparison operator here
};
} // namespace detail

namespace X {
struct GENPYBIND(inline_base("*")) Value : public Y::Value
{
    constexpr explicit Value(uintmax_t value = 0) GENPYBIND(implicit_conversion) : base_t(value) {}
};
} // namespace X

namespace Y {
struct GENPYBIND(inline_base("*")) Value : public detail::BaseType<Value, uint32_t>
{
    constexpr explicit Value(uintmax_t value = 0) GENPYBIND(implicit_conversion) : base_t(value) {}
};
} // namespace Y

yields

// FIXME: expose [Operator CursorKind.FUNCTION_DECL detail::operator==]
//        ('operator==', 2) -> (('eq', 'eq'), 'l == r')
//        ['const ::Y::Value', 'const ::Y::Timer::Value']

[muffgaga]

@kljohann suggested explicit using declarations.