begin
definition
let L be ( ( non
empty Lattice-like ) ( non
empty join-commutative join-associative meet-commutative meet-associative meet-absorbing join-absorbing Lattice-like )
Lattice) ;
let a,
b be ( ( ) ( )
Element of ( ( ) ( non
empty )
set ) ) ;
pred a is-upper-neighbour-of b means
(
a : ( ( non
empty ) ( non
empty )
set )
<> b : ( (
Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) ) (
Relation-like Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) )
Element of
bool [:[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) ( Relation-like ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) : ( ( ) ( )
set ) ) &
b : ( (
Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) ) (
Relation-like Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) )
Element of
bool [:[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) ( Relation-like ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) : ( ( ) ( )
set ) )
[= a : ( ( non
empty ) ( non
empty )
set ) & ( for
c being ( ( ) ( )
Element of ( ( ) ( )
set ) ) st
b : ( (
Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) ) (
Relation-like Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) )
Element of
bool [:[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) ( Relation-like ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) : ( ( ) ( )
set ) )
[= c : ( ( ) ( )
Element of ( ( ) ( non
empty )
set ) ) &
c : ( ( ) ( )
Element of ( ( ) ( non
empty )
set ) )
[= a : ( ( non
empty ) ( non
empty )
set ) & not
c : ( ( ) ( )
Element of ( ( ) ( non
empty )
set ) )
= a : ( ( non
empty ) ( non
empty )
set ) holds
c : ( ( ) ( )
Element of ( ( ) ( non
empty )
set ) )
= b : ( (
Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) ) (
Relation-like Function-like V20(
[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) ,
L : ( ( non
empty ) ( non
empty )
set ) ) )
Element of
bool [:[:L : ( ( non empty ) ( non empty ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) ( Relation-like ) set ) ,L : ( ( non empty ) ( non empty ) set ) :] : ( ( ) (
Relation-like )
set ) : ( ( ) ( )
set ) ) ) );
end;