dimensioned::make_units!

macro_rules! make_units { ($System:ident, $Unitless:ident, $one:ident; base { $($Type:ident, $constant:ident, $print_as:ident;)+ } derived {$($derived_constant:ident: $Derived:ident = $e:expr;)*} ) => (
    make_units_adv!{
        $System, $Unitless, $one, f64, 1.0;
        base {
            $(P1, $Type, $constant, $print_as;)*
        }
        derived {
            $($derived_constant: $Derived = $e;)*
        }
    }

    );
}