This function creates a constraint from a propagator. You can then add this constraint to a IloCPEngine instance during search in a user-defined goal. For example, using the propagator defined in the IloPropagatorI documentation:

       // Code to be executed inside a goal!
       IloPropagatorI * prop = new (env) SignI(x, sgn);
       IlcConstraint signCt = IlcCustomConstraint(solver, prop);
       cp.add(signCt);