summaryrefslogtreecommitdiff
path: root/plugins/micromega/Refl.v
blob: 499a8c4c48033184f8cf294e3717b1f6680559bd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
(* -*- coding: utf-8 -*- *)
(************************************************************************)
(*  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        *)
(************************************************************************)
(*                                                                      *)
(* Micromega: A reflexive tactic using the Positivstellensatz           *)
(*                                                                      *)
(*  Frédéric Besson (Irisa/Inria) 2006-2008                             *)
(*                                                                      *)
(************************************************************************)

Require Import List.
Require Setoid.

Set Implicit Arguments.

(* Refl of '->' '/\': basic properties *)

Fixpoint make_impl (A : Type) (eval : A -> Prop) (l : list A) (goal : Prop) {struct l} : Prop :=
  match l with
    | nil => goal
    | cons e l => (eval e) -> (make_impl eval l goal)
  end.

Theorem make_impl_true :
  forall (A : Type) (eval : A -> Prop) (l : list A), make_impl eval l True.
Proof.
induction l as [| a l IH]; simpl.
trivial.
intro; apply IH.
Qed.

Fixpoint make_conj (A : Type) (eval : A -> Prop) (l : list A) {struct l} : Prop :=
  match l with
    | nil => True
    | cons e nil => (eval e)
    | cons e l2 => ((eval e) /\ (make_conj eval l2))
  end.

Theorem make_conj_cons : forall (A : Type) (eval : A -> Prop) (a : A) (l : list A),
  make_conj eval (a :: l) <-> eval a /\ make_conj eval l.
Proof.
intros; destruct l; simpl; tauto.
Qed.


Lemma make_conj_impl : forall (A : Type) (eval : A -> Prop) (l : list A) (g : Prop),
  (make_conj eval l -> g) <-> make_impl eval l g.
Proof.
  induction l.
  simpl.
  tauto.
  simpl.
  intros.
  destruct l.
  simpl.
  tauto.
  generalize (IHl g).
  tauto.
Qed.

Lemma make_conj_in : forall (A : Type) (eval : A -> Prop) (l : list A),
  make_conj eval l -> (forall p, In p l -> eval p).
Proof.
  induction l.
  simpl.
  tauto.
  simpl.
  intros.
  destruct l.
  simpl in H0.
  destruct H0.
  subst; auto.
  tauto.
  destruct H.
  destruct H0.
  subst;auto.
  apply IHl; auto.
Qed.



Lemma make_conj_app : forall  A eval l1 l2, @make_conj A eval (l1 ++ l2) <-> @make_conj A eval l1 /\ @make_conj A eval l2.
Proof.
  induction l1.
  simpl.
  tauto.
  intros.
  change ((a::l1) ++ l2) with (a :: (l1 ++ l2)).
  rewrite make_conj_cons.
  rewrite IHl1.
  rewrite make_conj_cons.
  tauto.
Qed.

Lemma not_make_conj_cons : forall (A:Type) (t:A) a eval  (no_middle_eval : (eval t) \/ ~ (eval  t)),
  ~ make_conj  eval (t ::a) -> ~  (eval t) \/ (~ make_conj  eval a).
Proof.
  intros.
  simpl in H.
  destruct a.
  tauto.
  tauto.
Qed.

Lemma not_make_conj_app : forall (A:Type) (t:list A) a eval
  (no_middle_eval : forall d, eval d \/ ~ eval d) ,
  ~ make_conj  eval (t ++ a) -> (~ make_conj  eval t) \/ (~ make_conj eval a).
Proof.
  induction t.
  simpl.
  tauto.
  intros.
  simpl ((a::t)++a0)in H.
  destruct (@not_make_conj_cons _ _ _ _  (no_middle_eval a) H).
  left ; red ; intros.
  apply H0.
  rewrite  make_conj_cons in H1.
  tauto.
  destruct (IHt _ _ no_middle_eval H0).
  left ; red ; intros.
  apply H1.
  rewrite make_conj_cons in H2.
  tauto.
  right ; auto.
Qed.