module Columnize

def self.columnize(*args)

separating ', '
* whether to format as an array - with surrounding [] and
* whether to left justify text instead of right justify
* whether to ignore terminal codes in text size calculation
* A format specify for formatting each item each array item to a string
* a line suffix
* a line prefix
* a column separator
* the line display width
separated by two spaces. Options are available for setting
Each column is only as wide as necessary. By default, columns are

]
09, 10,
07, 08,
05, 06,
03, 04,
[01, 02,
:displaywidth => 10) =>
puts (1..10).to_a.columnize(:arrange_array => true, :colfmt => '%02d',
Formatted as an array using format specifier '%02d':

['1', '2,', '3', '4'] => '1 2\n3 4\n'
a.columnize(:arrange_vertical => false) =>
Arranged horizontally:

a.columnize => '1 3\n2 4\n'
Alternatively:

Columnize.columnize(a) => '1 3\n2 4\n'
a = (1..4).to_a
For example, for a line width of 4 characters (arranged vertically):

that when printed the columns are aligned.
Return a string from an array with embedded newlines formatted so

Columnize.columize([args]) => String 
def self.columnize(*args)
  list = args.shift
  opts = parse_columnize_options(args)
  Columnizer.new(list, opts).columnize
end

def self.included(base)

Adds columnize_opts to the singleton level of included class 
def self.included(base)
  # screw class variables, we'll use an instance variable on the class singleton
  class << base
    attr_accessor :columnize_opts
  end
  base.columnize_opts = DEFAULT_OPTS.dup
end

def self.parse_columnize_options(args)

+ljust+, and +line_prefix+.
are in the order: +displaywidth+, +colsep+, +arrange_vertical+,
In the older style positional arguments are used and the positions

newer style, +args+ is a hash where each key is one of the option names.
Options parsing routine for Columnize::columnize. In the preferred 
def self.parse_columnize_options(args)
  if 1 == args.size && args[0].kind_of?(Hash) # explicitly passed as a hash
    args[0]
  elsif !args.empty? # passed as ugly positional parameters.
    Hash[args.zip([:displaywidth, :colsep, :arrange_vertical, :ljust, :line_prefix]).map(&:reverse)]
  else
    {}
  end
end

def columnize(*args) 

def columnize(*args)
  return Columnize.columnize(*args) if args.length > 1
  opts = args.empty? ? {} : args.pop
  @columnize_opts ||= self.class.columnize_opts.dup
  @columnizer ||= Columnizer.new(self, @columnize_opts)
  # make sure that any changes to list or opts get passed to columnizer
  @columnizer.list = self unless @columnizer.list == self
  @columnizer.opts = @columnize_opts.merge(opts) unless @columnizer.opts == @columnize_opts and opts.empty?
  @columnizer.columnize
end