More on the Excludes Operator

As a top-level constraint, the excludes operator (excl(A, B)) creates a mutually exclusive relationship. The expression excl([A], [B]) means that if item A is in the solution, item B cannot be in the solution. It also means that if item B is in the solution, item A cannot be in the solution.

The exclude constraint can also be used with sub-expressions. For example, the following constraint excludes item B when item A's quantity is greater than 2. It also prevents item A from being greater than 2 when item B is in the solution.

excl(>([A],2),[B])