Domain Views for Constraint Programming
share
Views are a standard abstraction in constraint programming: They make it possible to implement a single version of each constraint, while avoiding to create new variables and constraints that would slow down propagation. Traditional constraint-programming systems provide the concept of variable views which implement a view of the type y = f(x) by delegating all (domain and constraint) operations on variable y to variable x. This paper proposes the alternative concept of domain views which only delegate domain operations. Domain views preserve the benefits of variable views but simplify the implementation of value-based propagation. Domain views also support non-injective views compositionally, expanding the scope of views significantly. Experimental results demonstrate the practical benefits of domain views.
READ FULL TEXT