[ANN]: ZeroDimensionalArrays.jl: zero-dimensional arrays/references/boxes

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Is that a bug?

julia> using ZeroDimensionalArrays, FillArrays

julia> fill(1) .+ 1
2

julia> Fill(1) .+ 1
0-dimensional Fill{Int64}, with entry equal to 2

julia> ZeroDimArray(1) .+ 1
2

Edit, found my issue about this. Original example was:

julia> real(fill(1+im))  # returns an array
0-dimensional Array{Int64, 0}:
1

julia> real(Fill(1+im))  # returns an array of arrays
0-dimensional Array{Fill{Int64, 0, Tuple{}}, 0}:
Fill(1)

But there’s another broadcasting difference, that Fill makes purity assumptions. This one I think is a choice, which FillArrays.jl does not regard as a bug:

julia> (_ -> rand()).(fill(1)) .+ zeros(2,3)  # ordinary fused broadcast
2×3 Matrix{Float64}:
 0.720996  0.162743  0.170527
 0.217833  0.417129  0.955952

julia> (_ -> rand()).(Fill(1)) .+ zeros(2,3)  # calls rand just once
2×3 Matrix{Float64}:
 0.72484  0.72484  0.72484
 0.72484  0.72484  0.72484

julia> (_ -> rand()).(ZeroDimArray(1)) .+ zeros(2,3)
2×3 Matrix{Float64}:
 0.0791902  0.467466  0.74044
 0.06619    0.701926  0.531931
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