X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fmatita%2Flibrary%2Flogic%2Fconnectives.ma;fp=helm%2Fmatita%2Flibrary%2Flogic%2Fconnectives.ma;h=4cbea3529a7ec983b39f814f1243f1a5f92568ab;hb=792b5d29ebae8f917043d9dd226692919b5d6ca1;hp=0000000000000000000000000000000000000000;hpb=a14a8c7637fd0b95e9d4deccb20c6abc98e8f953;p=helm.git diff --git a/helm/matita/library/logic/connectives.ma b/helm/matita/library/logic/connectives.ma new file mode 100644 index 000000000..4cbea3529 --- /dev/null +++ b/helm/matita/library/logic/connectives.ma @@ -0,0 +1,90 @@ +(**************************************************************************) +(* ___ *) +(* ||M|| *) +(* ||A|| A project by Andrea Asperti *) +(* ||T|| *) +(* ||I|| Developers: *) +(* ||T|| A.Asperti, C.Sacerdoti Coen, *) +(* ||A|| E.Tassi, S.Zacchiroli *) +(* \ / *) +(* \ / This file is distributed under the terms of the *) +(* v GNU Lesser General Public License Version 2.1 *) +(* *) +(**************************************************************************) + +set "baseuri" "cic:/matita/logic/connectives/". + +inductive True: Prop \def +I : True. + +default "true" cic:/matita/logic/connectives/True.ind. + +inductive False: Prop \def . + +default "false" cic:/matita/logic/connectives/False.ind. + +definition Not: Prop \to Prop \def +\lambda A. (A \to False). + +(*CSC: the URI must disappear: there is a bug now *) +interpretation "logical not" 'not x = (cic:/matita/logic/connectives/Not.con x). + +theorem absurd : \forall A,C:Prop. A \to \lnot A \to C. +intros. elim (H1 H). +qed. + +default "absurd" cic:/matita/logic/connectives/absurd.con. + +inductive And (A,B:Prop) : Prop \def + conj : A \to B \to (And A B). + +(*CSC: the URI must disappear: there is a bug now *) +interpretation "logical and" 'and x y = (cic:/matita/logic/connectives/And.ind#xpointer(1/1) x y). + +theorem proj1: \forall A,B:Prop. A \land B \to A. +intros. elim H. assumption. +qed. + +theorem proj2: \forall A,B:Prop. A \land B \to B. +intros. elim H. assumption. +qed. + +inductive Or (A,B:Prop) : Prop \def + or_introl : A \to (Or A B) + | or_intror : B \to (Or A B). + +(*CSC: the URI must disappear: there is a bug now *) +interpretation "logical or" 'or x y = + (cic:/matita/logic/connectives/Or.ind#xpointer(1/1) x y). + +theorem Or_ind': + \forall A,B:Prop. + \forall P: A \lor B \to Prop. + (\forall p:A. P (or_introl ? ? p)) \to + (\forall q:B. P (or_intror ? ? q)) \to + \forall p:A \lor B. P p. + intros. + apply + (match p return \lambda p.P p with + [(or_introl p) \Rightarrow H p + |(or_intror q) \Rightarrow H1 q]). +qed. + +definition decidable : Prop \to Prop \def \lambda A:Prop. A \lor \lnot A. + +inductive ex (A:Type) (P:A \to Prop) : Prop \def + ex_intro: \forall x:A. P x \to ex A P. + +(*CSC: the URI must disappear: there is a bug now *) +interpretation "exists" 'exists \eta.x = + (cic:/matita/logic/connectives/ex.ind#xpointer(1/1) _ x). + +notation < "hvbox(\exists ident i opt (: ty) break . p)" + right associative with precedence 20 +for @{ 'exists ${default + @{\lambda ${ident i} : $ty. $p)} + @{\lambda ${ident i} . $p}}}. + +inductive ex2 (A:Type) (P,Q:A \to Prop) : Prop \def + ex_intro2: \forall x:A. P x \to Q x \to ex2 A P Q. +