Integrate a few improvements on typeclasses and Program from the equations branch

and remove equations stuff which moves to a separate plugin.

Classes:
- Ability to define classes post-hoc from constants or inductive types.
- Correctly rebuild the hint database associated to local hypotheses when 
  they are changed by a [Hint Extern] in typeclass resolution.

Tactics and proofs:
- Change [revert] so that it keeps let-ins (but not [generalize]).
- Various improvements to the [generalize_eqs] tactic to make it more robust
  and produce the smallest proof terms possible.
  Move [specialize_hypothesis] in tactics.ml as it goes hand in hand with 
  [generalize_eqs].
- A few new general purpose tactics in Program.Tactics like [revert_until]
- Make transitive closure well-foundedness proofs transparent.
- More uniform testing for metas/evars in pretyping/unification.ml
  (might introduce a few changes in the contribs).

Program:
- Better sorting of dependencies in obligations.
- Ability to start a Program definition from just a type and no obligations, 
  automatically adding an obligation for this type.
- In compilation of Program's well-founded definitions, make the functional a
  separate definition for easier reasoning.
- Add a hint database for every Program populated by [Hint Unfold]s for 
  every defined obligation constant.


git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@12440 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 1 insertions, 1 deletions

diff --git a/theories/Program/Subset.v b/theories/Program/Subset.v
index a6aa4d524..89f477d8f 100644
--- a/theories/Program/Subset.v
+++ b/theories/Program/Subset.v
@@ -82,7 +82,7 @@ Qed.
    in tactics. *)
 
 Definition match_eq (A B : Type) (x : A) (fn : forall (y : A | y = x), B) : B :=
-  fn (exist _ x (refl_equal x)).
+  fn (exist _ x eq_refl).
 
 (* This is what we want to be able to do: replace the originaly matched object by a new,
    propositionally equal one. If [fn] works on [x] it should work on any [y | y = x]. *)