using StaticArrays, HybridArrays
typeof(SA[1 0;0 1]*HybridArray{Tuple{2,StaticArrays.Dynamic()}}([1 0;0 1]))
Returns Array{Int64,2}. However it can be determined at compile-time that this is actually a 2*n matrix, hence HybridArray{Tuple{2,StaticArrays.Dynamic()}}.