coqpp: add new ![] specifiers for structured proof interaction

![proof_stack] is equivalent to the old meaning of ![proof]: the body
has type `pstate:Proof_global.t option -> Proof_global.t option`

The other specifiers are for the following body types:

~~~
![open_proof] `is_ontop:bool -> pstate`

![maybe_open_proof] `is_ontop:bool -> pstate option`

![proof] `pstate:pstate -> pstate`

![proof_opt_query] `pstate:pstate option -> unit`

![proof_query] `pstate:pstate -> unit`
~~~

The `is_ontop` is only used for the warning message when declaring a
section variable inside a proof, we could also just stop warning.

The specifiers look closely related to stm classifiers, but currently
they're unconnected. Notably this means that a ![proof_query] doesn't
have to be classified QUERY.

![proof_stack] is only used by g_rewrite/rewrite whose behaviour I
 don't fully understand, maybe we can drop it in the future.

For compat we may want to consider keeping ![proof] with its old
meaning and using some new name for the new meaning. OTOH fixing
plugins to be stricter is easier if we change it as the errors tell us
where it's used.

1 files changed, 4 insertions, 4 deletions

diff --git a/plugins/ltac/g_ltac.mlg b/plugins/ltac/g_ltac.mlg
index 7eb34158e8..9bf5bd1bda 100644
--- a/plugins/ltac/g_ltac.mlg
+++ b/plugins/ltac/g_ltac.mlg
@@ -376,7 +376,7 @@ let () = declare_int_option {
 
 let vernac_solve ~pstate n info tcom b =
   let open Goal_select in
-  let pstate, status = Proof_global.with_current_proof (fun etac p ->
+  let pstate, status = Proof_global.with_proof (fun etac p ->
       let with_end_tac = if b then Some etac else None in
       let global = match n with SelectAll | SelectList _ -> true | _ -> false in
       let info = Option.append info !print_info_trace in
@@ -388,7 +388,7 @@ let vernac_solve ~pstate n info tcom b =
       let p = Proof.maximal_unfocus Vernacentries.command_focus p in
       p,status) pstate in
   if not status then Feedback.feedback Feedback.AddedAxiom;
-  Some pstate
+  pstate
 
 let pr_ltac_selector s = Pptactic.pr_goal_selector ~toplevel:true s
 
@@ -438,7 +438,7 @@ VERNAC { tactic_mode } EXTEND VernacSolve
 | ![ proof ] [ ltac_selector_opt(g) ltac_info_opt(n) tactic(t) ltac_use_default(def) ] =>
     { classify_as_proofstep } -> {
     let g = Option.default (Goal_select.get_default_goal_selector ()) g in
-    Vernacentries.vernac_require_open_proof vernac_solve g n t def
+    vernac_solve g n t def
   }
 | ![ proof ] [ "par" ":" ltac_info_opt(n) tactic(t) ltac_use_default(def) ] =>
     {
@@ -450,7 +450,7 @@ VERNAC { tactic_mode } EXTEND VernacSolve
       VtLater
     } -> {
       let t = rm_abstract t in
-      Vernacentries.vernac_require_open_proof vernac_solve Goal_select.SelectAll n t def
+      vernac_solve Goal_select.SelectAll n t def
     }
 END