Declarations.mli refactoring: module_type_body = module_body

 After this commit, module_type_body is a particular case of module_type.
 For a [module_type_body], the implementation field [mod_expr] is
 supposed to be always [Abstract]. This is verified by coqchk, even
 if this isn't so crucial, since [mod_expr] is never read in the case
 of a module type.

 Concretely, this amounts to the following rewrite on field names
 for module_type_body:
  - typ_expr --> mod_type
  - typ_expr_alg --> mod_type_alg
  - typ_* --> mod_*
 and adding two new fields to mtb:
  - mod_expr (always containing Abstract)
  - mod_retroknowledge (always containing [])

 This refactoring should be completely transparent for the user.

 Pros: code sharing, for instance subst_modtype = subst_module.
 Cons: a runtime invariant (mod_expr = Abstract) which isn't
 enforced by typing. I tried a polymorphic typing of mod_expr,
 to share field names while not having mtb = mb, but the OCaml
 typechecker isn't clever enough with polymorphic mutual fixpoints,
 and reject code sharing (e.g. between subst_modtype and subst_module).
 In the future (with ocaml>=4), some GADT could maybe help here,
 but for now the current solution seems good enough.

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/nativelibrary.ml b/kernel/nativelibrary.ml
index f33e1eaa6..ddd795917 100644
--- a/kernel/nativelibrary.ml
+++ b/kernel/nativelibrary.ml
@@ -47,13 +47,13 @@ and translate_field prefix mp env acc (l,x) =
 	Pp.msg_debug (Pp.str msg));
      translate_mod prefix mp env md.mod_type acc
   | SFBmodtype mdtyp ->
-     let mp = mdtyp.typ_mp in
+     let mp = mdtyp.mod_mp in
      (if !Flags.debug then
 	let msg =
 	  Printf.sprintf "Compiling module type %s..." (ModPath.to_string mp)
 	in
 	Pp.msg_debug (Pp.str msg));
-     translate_mod prefix mp env mdtyp.typ_expr acc
+     translate_mod prefix mp env mdtyp.mod_type acc
 
 let dump_library mp dp env mod_expr =
   if !Flags.debug then Pp.msg_debug (Pp.str "Compiling library...");