Integer values are used to represent boolean values. 1 repesents true and 0 represents false.
#/\and#\/or#\exclusive or#<==>equivalent#==>implication
Examples
?- X #/\ Y.
X = 1
Y = 1
yes
?- X #\/ Y, label([X,Y]).
X = 0
Y = 1
yes;
X = 1
Y = 0
yes;
X = 1
Y = 1
yes;
no
?- X #\ Y, label([X,Y]).
X = 0
Y = 1
yes;
X = 1
Y = 0
yes;
no
?- #\ X.
X = 0
yes
?- X #<==> Y, label([X,Y]).
X = 0
Y = 0
yes;
X = 1
Y = 1
yes;
no
?- X #==> Y, label([X,Y]).
X = 0
Y = 0
yes;
X = 0
Y = 1
yes;
X = 1
Y = 1
yes;
no
?- X #<== Y, label([X,Y]).
X = 0
Y = 0
yes;
X = 1
Y = 0
yes;
X = 1
Y = 1
yes;
no
?- X in 4..5, Y in 5..6, Z#<==> X#<Y, label([X,Y,Z]).
X = 4
Y = 5
Z = 1
yes;
X = 4
Y = 6
Z = 1
yes;
X = 5
Y = 5
Z = 0
yes;
X = 5
Y = 6
Z = 1
yes;
no
?- X in 2..3, X#<==>Y.
no
?- X #<==> append(_,_,_).
Cannot create CLP constraint from term: append(_, _, _)