An Observable of an abstract type

General Usage
1

I have an Observable (from https://github.com/JuliaGizmos/Observables.jl) that could contain any concrete subtype of some common abstract type. Is this the best way to do it?

using Observables
o = Observable(Any[])
o[] = [1] # update with an Int <: Real
o[] = [1.1] # update with a Float64 <: Real
2

@pfitzseb answered on slack#gizmos:

using Observables
o = Observable{Real}(1)
o[] = 1 # update with an Int <: Real
o[] = 1.1 # update with a Float64 <: Real