call (DataMapper::Validate::CustomValidator)

    # File lib/dm-validations/custom_validator.rb, line 18
          def call(target)
            #field_value = target.instance_variable_get("@#{@field_name}")
            #return true if @options[:allow_nil] && field_value.nil?

            #validation = (@options[:as] || @options[:with])
            #error_message = nil

            # Figure out what to use as the actual validator.
            # If a symbol is passed to :as, look up
            # the canned validation in FORMATS.
            #
            #validator = if validation.is_a? Symbol
            #  if FORMATS[validation].is_a? Array
            #    error_message = FORMATS[validation][1]
            #    FORMATS[validation][0]
            #  else
            #    FORMATS[validation] || validation
            #  end
            #else
            #  validation
            #end

            #valid = case validator
            #when Proc then validator.call(field_value)
            #when Regexp then validator =~ field_value
            #else raise UnknownValidationFormat, "Can't determine how to validate #{target.class}##{@field_name} with #{validator.inspect}"
            #end

            #unless valid
            #  field = Inflector.humanize(@field_name)
            #  value = field_value
            #
            #  error_message = @options[:message] || error_message || '%s is invalid'.t(field)
            #  error_message = error_message.call(field, value) if Proc === error_message
            #
            #  add_error(target, error_message, @field_name)
            #end

            #return valid
          end