    # File lib/facets/core/module/attr_validator.rb, line 7
      def attr_validator(*symbols, &validator)
        symbols.each do |symbol|
          define_method "#{symbol}=" do |val|
            unless validator.call(val)
              raise ArgumentError, "Invalid value provided for #{symbol}"
            end
            instance_variable_set("@#{symbol}", val)
          end
        end
      end