quantity(FloatType, unit) function

[MartinOtter]

Declaring a Unitful unit in a struct could be made nicer, if the following function quantity(..) is provided in Unitful:

using Unitful

# The following function should be defined inside Unitful
quantity(FloatType, unit) = Quantity{FloatType, dimension(unit), typeof(unit)} 

mutable struct Data{FloatType <: AbstractFloat}
    length::quantity(FloatType, u"m")
end

L = Data{Float64}(2.0u"mm")
@show L

Of course, it is easy to introduce such a function in an own package. However, it would be better if this feature is directly provided by Unitful.