10.10.4.2 Membership Constraints
domain(
+Variables,
+Min,
+Max)

where Variables is a list of domain variables or integers,
Min is an integer or the atom
inf
(minus infinity), and
Max is an integer or the atom sup
(plus infinity). True if
the variables all are elements of the range Min..
Max.
 ?X
in
+Range
reifiable 
defines a membership constraint. X is an integer or a domain
variable and Range is a ConstantRange (see Syntax of Indexicals). True if X is an element of the range.
 ?X
in_set
+FDSet
reifiable 
defines a membership constraint. X is an integer or a domain
variable and FDSet is an FD set (see FD Set Operations).
True if X is an element of the FD set.
in/2
and in_set/2
constraints maintain domainconsistency
and their reified versions detect domainentailment and disentailment.
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