Re-allowing assumptions during proofs seems safe now (fix #2411)

This restriction was introduce to solve #808, whose underlying
issue (causing a anomaly) doesn't seem active anymore.

Semantic:
 - Axiom in the middle of a proof : immediatly usable
   (just as a Definition)
 - Hypothesis or Variable : not visible in current proof, only
   usable in the next ones.

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@14470 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 27 insertions, 0 deletions

diff --git a/test-suite/bugs/closed/shouldsucceed/808_2411.v b/test-suite/bugs/closed/shouldsucceed/808_2411.v
new file mode 100644
index 000000000..1c13e7454
--- /dev/null
+++ b/test-suite/bugs/closed/shouldsucceed/808_2411.v
@@ -0,0 +1,27 @@
+Section test.
+Variable n:nat.
+Lemma foo: 0 <= n.
+Proof.
+(* declaring an Axiom during a proof makes it immediatly
+   usable, juste as a full Definition. *)
+Axiom bar : n = 1.
+rewrite bar.
+now apply le_S.
+Qed.
+
+Lemma foo' : 0 <= n.
+Proof.
+(* Declaring an Hypothesis during a proof is ok,
+   but this hypothesis won't be usable by the current proof(s),
+   only by later ones. *)
+Hypothesis bar' : n = 1.
+Fail rewrite bar'.
+Abort.
+
+Lemma foo'' : 0 <= n.
+Proof.
+rewrite bar'.
+now apply le_S.
+Qed.
+
+End test.
\ No newline at end of file