serif::dimensions::Luminosity serif::dimensions::PhysicalQuantity dimensions.hpp std::string_view std::string_view serif::dimensions::Luminosity::identifier identifier serif::dimensions::Luminosity::identifier = "luminosity" Dimension of Luminosity. serif::dimensions::Luminosity serif::dimensions::PhysicalQuantity serif::dimensions::Luminosity identifier serif::dimensions::PhysicalQuantity std::basic_string_view< Char > std::string_view serif::dimensions::Luminosityidentifier