print unnamed variables as __n

diff --git a/helm/software/components/ng_kernel/nCicPp.ml b/helm/software/components/ng_kernel/nCicPp.ml
index 5a96545fe3f0d2442b35a3f7a86ebf37933d1bb2..a0f0a8afb906c6f6991f47f3a5a6f8c23a9eed6d 100644 (file)
--- a/helm/software/components/ng_kernel/nCicPp.ml
+++ b/helm/software/components/ng_kernel/nCicPp.ml
@@ -49,8 +49,10 @@ let trivial_pp_term ~context ~subst ~metasenv ?(inside_fix=false) t =
   let module F = Format in
   let rec aux ?(toplevel=false) ctx = function
    | C.Rel m ->
-       (try F.fprintf f "%s" (List.nth ctx (m-1))
-       with Failure _ -> F.fprintf f " -%d" (m - List.length context))
+         (try 
+            let name = List.nth ctx (m-1) in
+            F.fprintf f "%s" (if name = "_" then "__"^string_of_int m else name)
+         with Failure _ -> F.fprintf f " -%d" (m - List.length context))
    | C.Const r -> F.fprintf f "%s" (r2s inside_fix r)
    | C.Prod ("_",s,t) -> 
        if not toplevel then F.fprintf f "(";