Why one(1u"kg") no dimension?

[liuyxpp]

Example below:

julia> using DynamicQuantities
julia> zero(1u"kg")
0.0 kg
julia> one(1u"kg")
1.0
julia> zero(1u"kg") |> dimension
kg
julia> one(1u"kg") |> dimension
# nothing displayed

I wonder why dimensions for the results of zero and one functions are different. Is it intentional or a bug?

[MilesCranmer]

This is the difference between one and oneunit. See https://docs.julialang.org/en/v1/base/numbers/#Base.oneunit

If you want a quantity that is of the same type as x, or of type T, even if x is dimensionful, use oneunit instead.

The way these are defined is that one is a multiplicative identity and zero is an additive identity. This is why one does not have units.

[MilesCranmer]

@liuyxpp on #136 you can find an alternative dimensions type that permits zero(::Type)