valid? (DataMapper::Validate::ConfirmationValidator)

    # File lib/dm-validations/confirmation_validator.rb, line 27
          def valid?(target)
            field_value = target.send(field_name)
            return true if @options[:allow_nil] && field_value.nil?
            return false if !@options[:allow_nil] && field_value.nil?

            if target.class.properties.has_property?(field_name)
              return true unless target.attribute_dirty?(field_name)
            end

            confirm_value = target.instance_variable_get("@#{@confirm_field_name}")
            field_value == confirm_value
          end