[Caml-list] Deleting a type alias while including a module

["Michael Grünewald" <michaelgrunewald@yahoo.fr>]

Dear list,

I am trying to use destructive substitution to remove a type alias in an 
inclusion. Some module XArray has the following signature:

XArray: sig
  type 'a xarray
  type 'a t
end

and I would like to remove the 'a t in the resulting signature. I thought

include (XArray : module type of XArray
   with 'a t := 'a XArray.xarray
)

would do, but it would not:

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 'a t = 'a XArray.xarray
        is not included in
          type 'a t = 'a xarray

Honestly, I do not really understand why the substitution can not 
happen, despite my careful reading of the documentation.  Any 
suggestions are welcome!
-- 
Michael