set "baseuri" "cic:/matita/PREDICATIVE-TOPOLOGY/coa_defs".
include "iff.ma".
-include "domain_defs.ma".
+include "domain_data.ma".
(* COMPLETE OVERLAP ALGEBRAS
*)
}.
coercion coa.
+
+definition zero: \forall (P:COA). P \def
+ \lambda (P:COA). inf P ? (dvoid_ixfam P).
+
+definition one: \forall (P:COA). P \def
+ \lambda (P:COA). sup P ? (dvoid_ixfam P).
+
+definition binf: \forall (P:COA). P \to P \to P \def
+ \lambda (P:COA). \lambda p0,p1.
+ inf P ? (dbool_ixfam P p0 p1).
+
+definition bsup: \forall (P:COA). P \to P \to P \def
+ \lambda (P:COA). \lambda p0,p1.
+ sup P ? (dbool_ixfam P p0 p1).
+
(*
inf_ov: forall p q, ov p q -> ov p (inf QDBool (bool_family _ p q))
properness: ov zero zero -> False;