A.9.17.2 Membership constraints

If you are using CLP(FD) to model and solve combinatorial tasks, then you typically need to specify the admissible domains of variables. The membership constraints in/2 and ins/2 are useful in such cases.

?Var in +Domain

Var is an element of Domain. Domain is one of:

Integer

Singleton set consisting only of Integer.

Lower .. Upper

All integers I such that Lower =< I =< Upper. Lower must be an integer or the atom inf, which denotes negative infinity. Upper must be an integer or the atom sup, which denotes positive infinity.

Domain1 \/ Domain2

The union of Domain1 and Domain2.

+Vars ins +Domain

The variables in the list Vars are elements of Domain. See in/2 for the syntax of Domain.