[FR] Store scalars/0-dimensional `DimArray` in `DimStack`?

[kapple19]

I find DimStacks preferable for many use cases as an alternative to structures.
However, in structures I can store scalar fields.
Can DimStack be updated to do so as well?

Can't instantiate a 0-dimensional DimArray for storing in a DimStack:

julia> DimArray(fill(12.34))
ERROR: MethodError: no method matching DimArray(::Array{Float64, 0})
The type `DimArray` exists, but no method is defined for this combination of argument types when trying to construct it.

Closest candidates are:
  DimArray(::AbstractArray, ::Union{Tuple, NamedTuple}; refdims, name, metadata)
   @ DimensionalData C:\Users\T0185914\.julia\packages\DimensionalData\0QEaa\src\array\array.jl:428
  DimArray(::AbstractArray, ::Any; kw...)
   @ DimensionalData C:\Users\T0185914\.julia\packages\DimensionalData\0QEaa\src\array\array.jl:427
  DimArray(::A, ::D, ::R, ::Na, ::Me) where {T, N, D<:Tuple, R<:Tuple, A<:AbstractArray{T, N}, Na, Me}
   @ DimensionalData C:\Users\T0185914\.julia\packages\DimensionalData\0QEaa\src\array\array.jl:419
  ...

Stacktrace:
 [1] top-level scope
   @ REPL[54]:1

But somehow this constructs a 0-dimensional DimArray:

julia> x = X(1:10)
X 1:10

julia> y = Y(2:0.1:4)
Y 2.0:0.1:4.0

julia> st1 = DimStack((; A = rand(x, y), B = rand(x, Z([1]))))
┌ 10×21×1 DimStack ┐
├──────────────────┴──────────────────────────────────────── dims ┐
  ↓ X Sampled{Int64} 1:10 ForwardOrdered Regular Points,
  → Y Sampled{Float64} 2.0:0.1:4.0 ForwardOrdered Regular Points,
  ↗ Z Sampled{Int64} [1] ForwardOrdered Irregular Points
├───────────────────────────────────────────────────────── layers ┤
  :A eltype: Float64 dims: X, Y size: 10×21
  :B eltype: Float64 dims: X, Z size: 10×1
└─────────────────────────────────────────────────────────────────┘

julia> st1[X = At(1), Y = At(2)].A
┌ 0-dimensional DimArray{Float64, 0} A ┐
└──────────────────────────────────────┘
0.885065

(I understand I am demonstrating the complaint that "users do weird things." 😅)

[rafaqz]

julia> DimArray(fill(0), ())
┌ 0-dimensional DimArray{Int64, 0} ┐
└──────────────────────────────────┘
0

You always need two arguments, data and dimensions. I know in this case dimensions could be inferred to be (), but I'm not sure we need a constructor for that edge case?

[kapple19]

Nah, I think it's nice to explicitly specify that it has no dimensions.

I think I'll close this issue then. Thanks!