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Subject: [Caml-list] Definition of module synonyms

Dear list,

Following the goal of providing module synonyms (e. g. abbreviations for lazy
developers), it seemed natural to do something along the following lines:

	module M : sig
	  type t = A
	  val x : t
	end = struct
	  type t = A
	  let x = A
	end
	module S : sig
	  type t = M.t = A
	  include module type of M with type t := M.t
	end = M

However, this is rejected with the following message:

	    include module type of M with type t := M.t
	            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
	Error: In this `with' constraint, the new definition of t
	       does not match its original definition in the constrained signature:
	       Type declarations do not match:
	         type t = M.t
	       is not included in
	         type t = A
	       Their kinds differ.

The very same problem arise when defining type "t" as a record, but not when
defining it as either an arrow type, or a polymorphic variant type. So my guess
is that I am missing something obvious about name scoping, but cannot just
get my finger on it.


Any insight would be greatly appreciated.


Regards,

Xavier Clerc