See - https://discourse.julialang.org/t/container-of-heterogeneous-types/22191 - https://discourse.julialang.org/t/is-there-a-way-to-forward-getindex-for-tuples-in-a-type-stable-way/2889 - https://discourse.julialang.org/t/type-stability-when-arguments-are-functions/4734/7
