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Diffstat (limited to 'theories/Numbers/Integer/Abstract/ZPred.v')
-rw-r--r-- | theories/Numbers/Integer/Abstract/ZPred.v | 54 |
1 files changed, 0 insertions, 54 deletions
diff --git a/theories/Numbers/Integer/Abstract/ZPred.v b/theories/Numbers/Integer/Abstract/ZPred.v deleted file mode 100644 index 4814ab086..000000000 --- a/theories/Numbers/Integer/Abstract/ZPred.v +++ /dev/null @@ -1,54 +0,0 @@ -Axiom succ_pred : forall x : Z, S (P x) == x. -Add Morphism P with signature E ==> E as pred_wd. - -Theorem pred_inj : forall x y, P x == P y -> x == y. -Proof. -intros x y H. -setoid_replace x with (S (P x)); [| symmetry; apply succ_pred]. -setoid_replace y with (S (P y)); [| symmetry; apply succ_pred]. -now rewrite H. -Qed. - -Theorem pred_succ : forall x, P (S x) == x. -Proof. -intro x. -apply succ_inj. -now rewrite succ_pred. -Qed. - -(* The following tactics are intended for replacing a certain -occurrence of a term t in the goal by (S (P t)) or by (P (S t)). -Unfortunately, this cannot be done by setoid_replace tactic for two -reasons. First, it seems impossible to do rewriting when one side of -the equation in question (succ_pred or pred_succ) is a variable, due to bug 1604. -This does not work even when the predicate is an identifier (e.g., -when one tries to rewrite (A x) into (A (S (P x)))). Second, the -setoid_rewrite tactic, like the ordinary rewrite tactic, does not -allow specifying the exact occurrence of the term to be rewritten. Now -while not in the setoid context, this occurrence can be specified -using the pattern tactic, it does not work with setoids, since pattern -creates a lambda abstractuion, and setoid_rewrite does not work with -them. *) - -Ltac rewrite_succP t set_tac repl thm := -let x := fresh "x" in -set_tac x t; -setoid_replace x with (repl x); [| symmetry; apply thm]; -unfold x; clear x. - -Tactic Notation "rewrite_succ_pred" constr(t) := -rewrite_succP t ltac:(fun x t => (set (x := t))) (fun x => (S (P x))) succ_pred. - -Tactic Notation "rewrite_succ_pred" constr(t) "at" integer(k) := -rewrite_succP t ltac:(fun x t => (set (x := t) in |-* at k)) (fun x => (S (P x))) succ_pred. - -Tactic Notation "rewrite_pred_succ" constr(t) := -rewrite_succP t ltac:(fun x t => (set (x := t))) (fun x => (P (S x))) pred_succ. - -Tactic Notation "rewrite_pred_succ" constr(t) "at" integer(k) := -rewrite_succP t ltac:(fun x t => (set (x := t) in |-* at k)) (fun x => (P (S x))) pred_succ. - -(* One can add tactic notations for replacements in assumptions rather -than in the goal. For the reason of many possible variants, the core -of the tactic is factored out. *) - |