1 files changed, 77 insertions, 0 deletions
diff --git a/theories/Compat/Coq84.v b/theories/Compat/Coq84.v
new file mode 100644
index 00000000..b04d5168
--- /dev/null
+++ b/theories/Compat/Coq84.v
@@ -0,0 +1,77 @@
+(************************************************************************)
+(*  v      *   The Coq Proof Assistant  /  The Coq Development Team     *)
+(* <O___,, *   INRIA - CNRS - LIX - LRI - PPS - Copyright 1999-2015     *)
+(*   \VV/  **************************************************************)
+(*    //   *      This file is distributed under the terms of the       *)
+(*         *       GNU Lesser General Public License Version 2.1        *)
+(************************************************************************)
+
+(** Compatibility file for making Coq act similar to Coq v8.4 *)
+(** See https://coq.inria.fr/bugs/show_bug.cgi?id=4319 for updates *)
+(** This is required in Coq 8.5 to use the [omega] tactic; in Coq 8.4, it's automatically available.  But ZArith_base puts infix ~ at level 7, and we don't want that, so we don't [Import] it. *)
+Require Coq.omega.Omega.
+Ltac omega := Coq.omega.Omega.omega.
+
+(** The number of arguments given in [match] statements has changed from 8.4 to 8.5. *)
+Global Set Asymmetric Patterns.
+
+(** See bug 3545 *)
+Global Set Universal Lemma Under Conjunction.
+
+(** In 8.4, [admit] created a new axiom; in 8.5, it just shelves the goal. *)
+Axiom proof_admitted : False.
+Ltac admit := clear; abstract case proof_admitted.
+
+(** In 8.5, [refine] leaves over dependent subgoals. *)
+Tactic Notation "refine" uconstr(term) := refine term; shelve_unifiable.
+
+(** In 8.4, [constructor (tac)] allowed backtracking across the use of [constructor]; it has been subsumed by [constructor; tac]. *)
+Ltac constructor_84 := constructor.
+Ltac constructor_84_n n := constructor n.
+Ltac constructor_84_tac tac := once (constructor; tac).
+
+Tactic Notation "constructor" := constructor_84.
+Tactic Notation "constructor" int_or_var(n) := constructor_84_n n.
+Tactic Notation "constructor" "(" tactic(tac) ")" := constructor_84_tac tac.
+
+(** Some tactic notations do not factor well with tactics; we add global parsing entries for some tactics that would otherwise be overwritten by custom variants. See https://coq.inria.fr/bugs/show_bug.cgi?id=4392. *)
+Tactic Notation "reflexivity" := reflexivity.
+Tactic Notation "assumption" := assumption.
+Tactic Notation "etransitivity" := etransitivity.
+Tactic Notation "cut" constr(c) := cut c.
+Tactic Notation "exact_no_check" constr(c) := exact_no_check c.
+Tactic Notation "vm_cast_no_check" constr(c) := vm_cast_no_check c.
+Tactic Notation "casetype" constr(c) := casetype c.
+Tactic Notation "elimtype" constr(c) := elimtype c.
+Tactic Notation "lapply" constr(c) := lapply c.
+Tactic Notation "transitivity" constr(c) := transitivity c.
+Tactic Notation "left" := left.
+Tactic Notation "eleft" := eleft.
+Tactic Notation "right" := right.
+Tactic Notation "eright" := eright.
+Tactic Notation "constructor" := constructor.
+Tactic Notation "econstructor" := econstructor.
+Tactic Notation "symmetry" := symmetry.
+Tactic Notation "split" := split.
+Tactic Notation "esplit" := esplit.
+
+Global Set Regular Subst Tactic.
+
+(** Some names have changed in the standard library, so we add aliases. *)
+Require Coq.ZArith.Int.
+Module Export Coq.
+  Module Export ZArith.
+    Module Int.
+      Module Z_as_Int.
+        Include Coq.ZArith.Int.Z_as_Int.
+        (* FIXME: Should these get a (compat "8.4")?  Or be moved to Z_as_Int, probably? *)
+        Notation plus := Coq.ZArith.Int.Z_as_Int.add (only parsing).
+        Notation minus := Coq.ZArith.Int.Z_as_Int.sub (only parsing).
+        Notation mult := Coq.ZArith.Int.Z_as_Int.mul (only parsing).
+      End Z_as_Int.
+    End Int.
+  End ZArith.
+End Coq.
+
+(** Many things now import [PeanoNat] rather than [NPeano], so we require it so that the old absolute names in [NPeano.Nat] are available. *)
+Require Coq.Numbers.Natural.Peano.NPeano.