> `vector-sized` package[1]. This does not directly support multi-dimensional indices as the size type parameter must be of kind KnownNat, but they can be neste

> `vector-sized` package[1]. This does not directly support multi-dimensional indices as the size type parameter must be of kind KnownNat, but they can be nested, Oh! That's neat. Nesting would eliminate the need for a list at the type level, and it seems to handle numbers at the type level. That's probably sufficient to write something like a function type (a -> b -> c) -> Vector x a -> Vector y b -> Vector x (Vector y c) Perhaps it can be an operator that can be chained setting the first argument to always be `(,)`. That might roughly do what the comma does in Julia's multidimensional comprehensions. The only bad part of this is that one wouldn't be able to define a Functor instance that works with arbitrary dimensions. It'd have to be one instance for 2 dimensions, one instance for 3 dimensions, etc. For that, I think a list at the type level holding the dimensions would be necessary. EDIT: No, the nesting would prevent proper chaining mentioned operator. Using such an operator twice would result in something like `Vector z (Vector y (Vector x (a, b), c))` instead of the slightly more desirable `Vector z (Vector y (Vector x (a, (b, c)))` that I was thinking. AFAICT, it doesn't seem that either of those suggestions is sufficient for type-safe multidimensional comprehensions in Haskell. They're better than what I found, but they still have their limitations.