exception Dont_match
val value_descriptions :
  Env.t ->
  Types.value_description ->
  Types.value_description -> Typedtree.module_coercion
val type_declarations :
  Env.t ->
  Ident.t -> Types.type_declaration -> Types.type_declaration -> bool
val exception_declarations :
  Env.t -> Types.exception_declaration -> Types.exception_declaration -> bool