Providing {N} with type alias

General Usage
4

Subtyping StaticArray here is making this more confused because it’s adding a different codepath on the abstract type. The crux is that Julia doesn’t automatically create a constructor that fills in some of the parameters:

julia> struct C{N,T}
           data::NTuple{N,T}
       end

julia> C((1,2,3))
C{3, Int64}((1, 2, 3))

julia> C{3}((1,2,3))
ERROR: MethodError: no method matching (C{3})(::Tuple{Int64, Int64, Int64})
Stacktrace:
 [1] top-level scope
   @ REPL[2]:1

julia> C{3,Int}((1,2,3))
C{3, Int64}((1, 2, 3))

You can define this constructor yourself:

julia> (::Type{C{N}})(d::NTuple{N,T}) where {N,T} = C{N,T}(d)

julia> C{3}((1,2,3))
C{3, Int64}((1, 2, 3))
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