From: Claudio Sacerdoti Coen <claudio.sacerdoticoen@unibo.it>
Date: Thu, 6 Dec 2012 13:03:09 +0000 (+0000)
Subject: Bug fixed: %n was badly failing (with Failure "nth") when n was
X-Git-Tag: make_still_working~1411
X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=commitdiff_plain;h=41dfa9c8a69428f59683f5ab964b217c67ebe46e;p=helm.git

Bug fixed: %n was badly failing (with Failure "nth") when n was
not a valid constructor. Now fail is raised (to be captured by
try, etc.)
---

diff --git a/matita/components/ng_tactics/nTactics.ml b/matita/components/ng_tactics/nTactics.ml
index 044f496f1..6870dab57 100644
--- a/matita/components/ng_tactics/nTactics.ml
+++ b/matita/components/ng_tactics/nTactics.ml
@@ -624,9 +624,9 @@ let case1_tac name =
 ;;
 
 let constructor_tac ?(num=1) ~args = distribute_tac (fun status goal ->
-  if num < 1 then fail (lazy "constructor numbers begin with 1");
   let gty = get_goalty status goal in
-  let status, (r,_,_,_) = analyse_indty status gty in
+  let status, (r,consno,_,_) = analyse_indty status gty in
+  if num < 1 || num > consno then fail (lazy "Non existant constructor");
   let ref = NReference.mk_constructor num r in
   let t = 
     if args = [] then Ast.NRef ref else