# File lib/data_mapper/constraints/relationship/one_to_many.rb, line 9
        def enforce_destroy_constraint(resource)
          return true unless association = get(resource)

          constraint = self.constraint

          case constraint
          when :protect
            Array(association).empty?
          when :destroy, :destroy!
            association.__send__(constraint)
          when :set_nil
            Array(association).all? do |resource|
              resource.update(inverse => nil)
            end
          when :skip
            true  # do nothing
          end
        end