mp_units::get_common_unit

[[nodiscard]]
consteval
Unit auto
get_common_unit(auto u);

template<
    Unit... Us,
    /* implementation-defined */ NewUnit>
[[nodiscard]]
consteval
Unit auto
get_common_unit(
    NewUnit nu,
    common_unit<Us...> cu);

template<
    Unit U1,
    /* implementation-defined */ U2>
[[nodiscard]]
consteval
Unit auto
get_common_unit(
    U1 u1,
    U2 u2);

template<
    Unit... Us,
    /* implementation-defined */ NewUnit>
[[nodiscard]]
consteval
Unit auto
get_common_unit(
    common_unit<Us...>,
    NewUnit);

template<
    Unit Front,
    Unit... Rest,
    Unit... Us>
requires (detail::UnitConvertibleTo<common_unit<Front, Rest...>, common_unit<Us...>{}>)
[[nodiscard]]
consteval
Unit auto
get_common_unit(
    common_unit<Front, Rest...>,
    common_unit<Us...>);

[[nodiscard]]
consteval
Unit auto
get_common_unit(
    auto u1,
    auto u2,
    auto u3,
    auto... rest)
requires requires { get_common_unit(get_common_unit(u1, u2), u3, rest...); };