Renaming types in a module signature

Learning
1

I am wondering if there is a way to rename a type in a module signature.

It can be done with destructive substitution if the type is an abstract one:

module type S = sig
  type t (* needs to be renamed *)
  (* some type's and val's that use type t *)
end
module type S' = sig
  type renamed
  include S with type t := renamed
end

This gives a new module type, S’, that is like S but naming it’s type renamed instead of t…

… But unfortunately this approach fails, or at least, becomes very cumbersome, when t depends on other types, for example:

module type S = sig
  type r
  type s = r -> r
  type t (* needs to be renamed *) = s * s
end
module type S' = sig
  (* here we also have to do a destructive substitution for types t depends on! *)
  type r
  type s = r -> r
  type renamed = s * s
  include S
    with type r := r
     and type s := s
     and type t := renamed
end

Here, to use destructive substitution, we have to also replace types that are used to define t!

Is there a more elegant way, that does not needs you to redefine all the types the one you want to rename depends on?

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