def valid?(format=@config[:local_format]||:conventional)
      if @config[:mailbox_validator].is_a?(Proc)
        @config[:mailbox_validator].call(self.mailbox, self.tag)
      elsif format.is_a?(Proc)
        format.call(self)
      elsif format == :conventional
        self.conventional?
      elsif format == :relaxed
        self.relaxed?
      elsif format == :redacted
        self.redacted?
      elsif format == :standard
        self.standard?
      elsif format == :none
        true
      else
        raise "Unknown format #{format}"
      end
    end
def valid?(format=@config[:local_format]||:conventional)
      if @config[:mailbox_validator].is_a?(Proc)
        @config[:mailbox_validator].call(self.mailbox, self.tag)
      elsif format.is_a?(Proc)
        format.call(self)
      elsif format == :conventional
        self.conventional?
      elsif format == :relaxed
        self.relaxed?
      elsif format == :redacted
        self.redacted?
      elsif format == :standard
        self.standard?
      elsif format == :none
        true
      else
        raise "Unknown format #{format}"
      end
    end
Validations

 True if the part is valid according to the configurations