-- | /O(1)/ First element
head :: G.Vector (Vector k) (Rec (TaggedFunctor Identity) rs)
  => (Vector k) (Rec (TaggedFunctor Identity) rs) -> Rec (TaggedFunctor Identity) rs
head = G.head
head :: G.Vector (Vector k) (Rec (TaggedFunctor Identity) rs)
  => (Vector k) (Rec (TaggedFunctor Identity) rs) -> Rec (TaggedFunctor Identity) rs
head = G.head
head = G.head