Makes the new Proofview.tactic the basic type of Ltac.

On the compilation of Coq, we can see an increase of ~20% compile time on
my completely non-scientific tests. Hopefully this can be fixed.

There are a lot of low hanging fruits, but this is an iso-functionality commit.
With a few exceptions which were not necessary for the compilation of the theories:
- The declarative mode is not yet ported
- The timeout tactical is currently deactivated because it needs some subtle
I/O. The framework is ready to handle it, but I haven't done it yet.
-  For much the same reason, the ltac debugger is unplugged. It will be more
difficult, but will eventually be back.

A few comments:
I occasionnally used a coercion from [unit Proofview.tactic] to the old
[Prooftype.tactic]. It should work smoothely, but loses any backtracking
information: the coerced tactics has at most one success.
- It is used in autorewrite (it shouldn't be a problem there). Autorewrite's
code is fairly old and tricky
- It is used in eauto, mostly for "Hint Extern". It may be an issue as time goes
as we might want to have various success in a "Hint Extern". But it would
require a heavy port of eauto.ml4
- It is used in typeclass eauto, but with a little help from Matthieu, it should
be easy to port the whole thing to the new tactic engine, actually simplifying
the code.
- It is used in fourier. I believe it to be inocuous.
- It is used in firstorder and congruence. I think it's ok. Their code is
somewhat intricate and I'm not sure they would be easy to actually port.
- It is used heavily in Function. And honestly, I have no idea whether it can do
harm or not.

Updates:
(11 June 2013) Pierre-Marie Pédrot contributed the rebase over his new stream based
architecture for Ltac matching (r16533), which avoid painfully and expensively
working around the exception-throwing control flow of the previous API.
(11 October 2013) Rebasing over recent commits (somewhere in r16721-r16730)
rendered a major bug in my implementation of Tacticals.New.tclREPEAT_MAIN
apparent. It caused Field_theory.v to loop. The bug made rewrite !lemma,
rewrite ?lemma and autorewrite incorrect (tclREPEAT_MAIN was essentially
tclREPEAT, causing rewrites to be tried in the side-conditions of conditional
rewrites as well). The new implementation makes Coq faster, but it is
pretty much impossible to tell if it is significant at all.

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@16967 85f007b7-540e-0410-9357-904b9bb8a0f7

1 files changed, 7 insertions, 0 deletions

diff --git a/proofs/clenvtac.ml b/proofs/clenvtac.ml
index a79c9f978..76cf41c50 100644
--- a/proofs/clenvtac.ml
+++ b/proofs/clenvtac.ml
@@ -83,6 +83,13 @@ let elim_res_pf_THEN_i clenv tac gls =
   let clenv' = (clenv_unique_resolver ~flags:elim_flags clenv gls) in
   tclTHENLASTn (clenv_refine false clenv') (tac clenv') gls
 
+open Proofview.Notations
+let new_elim_res_pf_THEN_i clenv tac =
+  Tacmach.New.of_old (clenv_unique_resolver ~flags:elim_flags clenv) >>- fun clenv' ->
+  Proofview.tclTHEN
+    (Proofview.V82.tactic (clenv_refine false clenv'))
+    (Proofview.tclEXTEND [] (Proofview.tclUNIT()) (Array.to_list (tac clenv')))
+
 let e_res_pf clenv = res_pf clenv ~with_evars:true ~flags:dft