Advice for copyto! and staticarrays

[rveltz]

Hello,

I would like to use copyto! in my code. So I created a

_copyto!!(x::AbstractArray, y::AbstractArray) = copyto!(x,y)
_copyto!!(x,y) = VI.add!!(x, y, VI.One(), VI.Zero())

I would like to use _copyto!! on StaticArrays but it will fall back to copyto!(x,y) in the above code because they are AbstractArray.
Apart from adding StaticArray as a dependecny and adding the methods _copyto!!(x::SA,y::SA), do you see a better way using the framework of VectorInterface?

[lkdvos]

I'm not sure if there really is a way to make this work automatically without writing some dedicated code, depending on how much you really need this to be Base.copyto! in the generic case.

I think you could realistically use scale!!(y, x, One()), combined with the current VectorInterface patch should at least give you the same external behavior, even though VectorInterface will not actually fall back to copyto! directly.

Alternatively, I vaguely remember ArrayInterface.jl having an ismutable trait, so if you are okay with depending on that you could achieve a similar effect by leveraging that trait.

Hope this helps!