Using parametric type inside outer parametric constructor

[CameronBieganek]

I’m still a bit confused. The suggestion from @lmiq made me wonder about a related question that seems odd to me. I’ve opened a separate thread for that specific question:

If parametric types are invariant, why is Vector{Int} a subtype of AbstractVector{Int}?

If parametric types are invariant, why is Vector{Int} a subtype of AbstractVector{Int}? julia> Vector{Int} <: AbstractVector{Int} true A somewhat more complete and self-contained example: julia> abstract type Animal{T} end julia> struct Cat{T} <: Animal{T} end julia> Int <: Real true julia> Cat{Int} <: Animal{Real} false julia> Int <: Int true julia> Cat{Int} <: Animal{Int} true Since parametric types are supposed to be invariant, it seems like there should be no subtype relationship be…