Class IlcAnyPredicateI

IlcAnyPredicateI is the implementation class of IlcAnyPredicate, which makes it possible for you to define predicates on arbitrary objects in Solver. A predicate is an object with a method (IlcAnyPredicateI::isTrue) that checks whether or not a property is satisfied by an ordered set of (pointers to) objects. Conventionally in Solver, the ordered set of objects is represented by an instance of IlcIntArray.

Defining a New Class of Predicates

Predicates, like other Solver objects, depend on two classes: a handle class, IlcAnyPredicate, and an implementation class, IlcAnyPredicateI, where an object of the handle class contains a data member (the handle pointer) that points to an object (its implementation object) of an instance of IlcAnyPredicateI allocated on the Solver heap. As a Solver user, you will be working primarily with handles.

If you define a new class of predicates yourself, you must define its implementation class together with the corresponding virtual member function isTrue, as well as a member function that returns an instance of the handle class IlcAnyPredicate.

Arity

As a developer, you can use predicates in Solver applications to define your own constraints that have not already been predefined in Solver. In that case, the arity of the predicate (that is, the number of constrained variables involved in the predicate, and thus the size of the array that the member function IlcAnyPredicateI::isTrue must check) must be less than or equal to three.

This constructor creates an implementation object of a predicate. This constructor should not be called directly because this is an abstract class. This constructor is called automatically in the constructors of its subclasses.

As this class is to be subclassed, a virtual destructor is provided.

This member function must be redefined when you derive a new subclass of IlcAnyPredicateI. This member function must return IlcTrue if the invoking predicate is satisfied by the elements contained in the array val. Otherwise, it must return IlcFalse.