Vernac classification streamlined (handles VERNAC EXTEND)

The warning output by vernacextend when the classifier is missing
is the documentation of this commit:

Warning: Vernac entry "Foo" misses a classifier. A classifier is a
function that returns an expression of type vernac_classification (see
Vernacexpr). You can:
- Use '... EXTEND Foo CLASSIFIED AS QUERY ...' if the new
  vernacular command does not alter the system state;
- Use '... EXTEND Foo CLASSIFIED AS SIDEFF ...' if the new
  vernacular command alters the system state but not the parser nor it starts
  a proof or ends one;
- Use '... EXTEND Foo CLASSIFIED BY f ...' to specify a global
  function f.  The function f will be called passing "Foo" as the
  only argument;
- Add a specific classifier in each clause using the syntax:
  '[...] => [ f ] -> [...]'.
Specific classifiers have precedence over global classifiers. Only one
classifier is called.

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@16680 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 11 insertions, 3 deletions

diff --git a/toplevel/vernac_classifier.mli b/toplevel/vernac_classifier.mli
index 06535d512..d6bc8b886 100644
--- a/toplevel/vernac_classifier.mli
+++ b/toplevel/vernac_classifier.mli
@@ -8,13 +8,21 @@
 
 open Stateid
 open Vernacexpr
+open Genarg
 
 val string_of_vernac_classification : vernac_classification -> string
 
 (** What does a vernacular do *)
 val classify_vernac : vernac_expr -> vernac_classification
 
-(** Install an additional vernacular classifier (that has precedence over
-    all classifiers already installed) *)
+(** Install a vernacular classifier for VernacExtend *)
 val declare_vernac_classifier :
-  string -> (vernac_expr -> vernac_classification) -> unit
+  string -> (raw_generic_argument list -> unit -> vernac_classification) -> unit
+
+(** Set by Stm *)
+val set_undo_classifier : (vernac_expr -> vernac_classification) -> unit
+
+(** Standard constant classifiers *)
+val classify_as_query : vernac_classification
+val classify_as_sideeff : vernac_classification
+