prim notations backtrackable, their declarations now in two parts (API change)

 The first part (e.g. register_bignumeral_interpretation) deals only with
 the interp/uninterp closures. It should typically be done as a side
 effect during a syntax plugin loading. No prim notation are active yet
 after this phase.

 The second part (enable_prim_token_interpretation) activates the prim
 notation. It is now correctly talking to Summary and to the LibStack.
 To avoid "phantom" objects in libstack after a mere Require, this
 second part should be done inside a Mltop.declare_cache_obj

 The link between the two parts is a prim_token_uid (a string), which
 should be unique for each primitive notation. When this primitive
 notation is specific to a scope, the scope_name could be used as uid.

 Btw, the list of "patterns" for detecting when an uninterpreter should
 be considered is now restricted to a list of global_reference
 (inductive constructors, or injection functions such as IZR).
 The earlier API was accepting a glob_constr list, but was actually
 only working well for global_reference.

 A minimal compatibility is provided (declare_numeral_interpreter),
 but is discouraged, since it is known to store uncessary objects
 in the libstack.

1 files changed, 14 insertions, 4 deletions

diff --git a/plugins/syntax/nat_syntax.ml b/plugins/syntax/nat_syntax.ml
index e158e0b516..85cb49586d 100644
--- a/plugins/syntax/nat_syntax.ml
+++ b/plugins/syntax/nat_syntax.ml
@@ -78,8 +78,18 @@ let uninterp_nat (AnyGlobConstr p) =
 (************************************************************************)
 (* Declare the primitive parsers and printers *)
 
+open Notation
+
+let nat_scope = "nat_scope"
+
+let at_declare_ml_module f x =
+  Mltop.declare_cache_obj (fun () -> f x) __coq_plugin_name
+
 let _ =
-  Notation.declare_numeral_interpreter "nat_scope"
-    (nat_path,datatypes_module_name)
-    nat_of_int
-    ([DAst.make @@ GRef (glob_S,None); DAst.make @@ GRef (glob_O,None)], uninterp_nat, true)
+  register_bignumeral_interpretation nat_scope (nat_of_int,uninterp_nat);
+  at_declare_ml_module enable_prim_token_interpretation
+    { pt_scope = nat_scope;
+      pt_uid = nat_scope;
+      pt_required = (nat_path,datatypes_module_name);
+      pt_refs = [glob_S; glob_O];
+      pt_in_match = true }