What about an `undefs` function in `Base`?

General Usage
62

Funny that SA doesn’t work with comprehensions.

julia> SA[1, 2, 3]
3-element SVector{3, Int64} with indices SOneTo(3):
 1
 2
 3

julia> SA[x for x=1:3]
ERROR: MethodError: Cannot `convert` an object of type
  Int64 to an object of type
  SA

So for comprehensions, you have to use the macro? Sidenote, the space between the macrocall and the brackets is optional:

julia> SArray[@SArray[1,2,3] for _=1:4]
4-element Vector{SArray}:
 [1, 2, 3]
 [1, 2, 3]
 [1, 2, 3]
 [1, 2, 3]

julia> @SArray[@SArray[1,2,3] for _=1:4]
4-element SVector{4, SVector{3, Int64}} with indices SOneTo(4):
 [1, 2, 3]
 [1, 2, 3]
 [1, 2, 3]
 [1, 2, 3]