This constructor takes advantage of a technique for Ruby object construction introduced by Andy Hunt and Dave Thomas (see reference), where optional values are set using commands in a block.

Text::Format.new {
    columns         = 72
    left_margin     = 0
    right_margin    = 0
    first_indent    = 4
    body_indent     = 0
    format_style    = Text::Format::LEFT_ALIGN
    extra_space     = false
    abbreviations   = {}
    tag_paragraph   = false
    tag_text        = []
    nobreak         = false
    nobreak_regex   = {}
    tabstop         = 8
    text            = nil
}

As shown above, arg is optional. If arg is specified and is a String, then arg is used as the default value of #text. Alternately, an existing Text::Format object can be used or a Hash can be used. With all forms, a block can be specified.

Source Code

# File action_mailer/vendor/text-format-0.6.3/text/format.rb, line 963
def initialize(arg = nil, &block)
  case arg
  when Text::Format
    __create(arg.text) do
      @columns        = arg.columns
      @tabstop        = arg.tabstop
      @first_indent   = arg.first_indent
      @body_indent    = arg.body_indent
      @format_style   = arg.format_style
      @left_margin    = arg.left_margin
      @right_margin   = arg.right_margin
      @extra_space    = arg.extra_space
      @tag_paragraph  = arg.tag_paragraph
      @tag_text       = arg.tag_text
      @abbreviations  = arg.abbreviations
      @nobreak        = arg.nobreak
      @nobreak_regex  = arg.nobreak_regex
      @text           = arg.text
      @hard_margins   = arg.hard_margins
      @split_words    = arg.split_words
      @split_rules    = arg.split_rules
      @hyphenator     = arg.hyphenator
    end
    instance_eval(&block) unless block.nil?
  when Hash
    __create do
      @columns       = arg[:columns]       || arg['columns']       || @columns
      @tabstop       = arg[:tabstop]       || arg['tabstop']       || @tabstop
      @first_indent  = arg[:first_indent]  || arg['first_indent']  || @first_indent
      @body_indent   = arg[:body_indent]   || arg['body_indent']   || @body_indent
      @format_style  = arg[:format_style]  || arg['format_style']  || @format_style
      @left_margin   = arg[:left_margin]   || arg['left_margin']   || @left_margin
      @right_margin  = arg[:right_margin]  || arg['right_margin']  || @right_margin
      @extra_space   = arg[:extra_space]   || arg['extra_space']   || @extra_space
      @text          = arg[:text]          || arg['text']          || @text
      @tag_paragraph = arg[:tag_paragraph] || arg['tag_paragraph'] || @tag_paragraph
      @tag_text      = arg[:tag_text]      || arg['tag_text']      || @tag_text
      @abbreviations = arg[:abbreviations] || arg['abbreviations'] || @abbreviations
      @nobreak       = arg[:nobreak]       || arg['nobreak']       || @nobreak
      @nobreak_regex = arg[:nobreak_regex] || arg['nobreak_regex'] || @nobreak_regex
      @hard_margins  = arg[:hard_margins]  || arg['hard_margins']  || @hard_margins
      @split_rules   = arg[:split_rules] || arg['split_rules'] || @split_rules
      @hyphenator    = arg[:hyphenator] || arg['hyphenator'] || @hyphenator
    end
    instance_eval(&block) unless block.nil?
  when String
    __create(arg, &block)
  when NilClass
    __create(&block)
  else
    raise TypeError
  end
end