[econstr] Continue consolidation of EConstr API under `interp`.

This commit was motivated by true spurious conversions arising in my
`to_constr` debug branch.

The changes here need careful review as the tradeoffs are subtle and
still a lot of clean up remains to be done in `vernac/*`.

We have opted for penalize [minimally] the few users coming from true
`Constr`-land, but I am sure we can tweak code in a much better way.

In particular, it is not clear if internalization should take an
`evar_map` even in the cases where it is not triggered, see the
changes under `plugins` for a good example.

Also, the new return type of `Pretyping.understand` should undergo
careful review.

We don't touch `Impargs` as it is not clear how to proceed, however,
the current type of `compute_implicits_gen` looks very suspicious as
it is called often with free evars.

Some TODOs are:

- impargs was calling whd_all, the Econstr equivalent can be either
  + Reductionops.whd_all [which does refolding and no sharing]
  + Reductionops.clos_whd_flags with all as a flag.

3 files changed, 17 insertions, 3 deletions

diff --git a/dev/base_include b/dev/base_include
index 350ccaa10..39e3ef2bd 100644
--- a/dev/base_include
+++ b/dev/base_include
@@ -196,7 +196,10 @@ let parse_tac    = Pcoq.parse_string Ltac_plugin.Pltac.tactic;;
 (* build a term of type glob_constr without type-checking or resolution of 
    implicit syntax *)
 
-let e s = Constrintern.intern_constr (Global.env()) (parse_constr s);;
+let e s =
+  let env = Global.env () in
+  let sigma = Evd.from_env env in
+  Constrintern.intern_constr env sigma (parse_constr s);;
 
 (* build a term of type constr with type-checking and resolution of 
    implicit syntax *)
diff --git a/dev/ci/user-overlays/06511-ejgallego-econstr+more_fix.sh b/dev/ci/user-overlays/06511-ejgallego-econstr+more_fix.sh
new file mode 100644
index 000000000..4b681909d
--- /dev/null
+++ b/dev/ci/user-overlays/06511-ejgallego-econstr+more_fix.sh
@@ -0,0 +1,7 @@
+ if [ "$CI_PULL_REQUEST" = "6511" ] || [ "$CI_BRANCH" = "econstr+more_fix" ]; then
+    ltac2_CI_BRANCH=econstr+more_fix
+    ltac2_CI_GITURL=https://github.com/ejgallego/ltac2
+
+    Equations_CI_BRANCH=econstr+more_fix
+    Equations_CI_GITURL=https://github.com/ejgallego/Coq-Equations
+fi
diff --git a/dev/top_printers.ml b/dev/top_printers.ml
index f99e2593d..2c983fd8d 100644
--- a/dev/top_printers.ml
+++ b/dev/top_printers.ml
@@ -313,6 +313,8 @@ let constr_display csr =
   in
   pp (str (term_display csr) ++fnl ())
 
+let econstr_display c = constr_display EConstr.Unsafe.(to_constr c) ;;
+
 open Format;;
 
 let print_pure_constr csr =
@@ -452,6 +454,8 @@ let print_pure_constr csr =
 	print_string (Printexc.to_string e);print_flush ();
 	raise e
 
+let print_pure_econstr c = print_pure_constr EConstr.Unsafe.(to_constr c) ;;
+
 let pploc x = let (l,r) = Loc.unloc x in
   print_string"(";print_int l;print_string",";print_int r;print_string")"
 
@@ -505,7 +509,7 @@ let _ =
       (function
          [c] when genarg_tag c = unquote (topwit wit_constr) && true ->
            let c = out_gen (rawwit wit_constr) c in
-           (fun ~atts ~st -> in_current_context constr_display c; st)
+           (fun ~atts ~st -> in_current_context econstr_display c; st)
        | _ -> failwith "Vernac extension: cannot occur")
   with
     e -> pp (CErrors.print e)
@@ -521,7 +525,7 @@ let _ =
       (function
          [c] when genarg_tag c = unquote (topwit wit_constr) && true ->
            let c = out_gen (rawwit wit_constr) c in
-           (fun ~atts ~st -> in_current_context print_pure_constr c; st)
+           (fun ~atts ~st -> in_current_context print_pure_econstr c; st)
        | _ -> failwith "Vernac extension: cannot occur")
   with
     e -> pp (CErrors.print e)