irc-aug-28.rb

#!/usr/bin/env ruby

require "strscan"

class Scanner
  def initialize(str, index)
    start = str.rindex(/\b/, index)
    @scanner = StringScanner.new(str)
    @scanner.pos = start
  end

  def scan
    word_1 = @scanner.scan(/\w+/)
    @scanner.skip(/[\s\b]+/) # Ignore whitespace, comma, period, etc
    word_2 = @scanner.scan(/\w+/)

    "#{word_1} #{word_2}"
  end
end

str = "peter is a jolly fellow, and my, clarice and him sure are a fit so mellow"
pos = ARGV[0] ? ARGV[0].to_i : 12
print "\n  #{str}\n  #{' '*pos}^\n\n=> "

pp Scanner.new(str, pos).scan