Trying to update for Ruby 1.9+

tp.taskpaper

Test project 1:
  - test task 2 @testTag
  - test task 2

Test project 2:
  - project 2 task 1
  - project 2 task 3
  
  Test sub project:
    - sub project task 1 @testTag2
    - sub project task 3
    Test sub sub project:
      - sub sub project task 1
      - sub sub project task 3
  
Archive:
  - test task 1 @testTag @testTag2 @done(2013-02-10) @project(Test project 1)
  - sub project task 2 @testTag @done(2013-02-10) @project(Test project 2 / Test sub project)
  - sub sub project task 2 @testTag2 @done(2013-02-10) @project(Test project 2 / Test sub project / Test sub sub project)
  - project 2 task 2 @done(2013-02-04) @project(Test project 2)

tp2md.rb

# TaskPaper to Markdown converter
# Usage: tp2md.rb filename.taskpaper > output.md

# updated to use FileUtils lib instead of ftools
# removed explicit hashbang ruby library path (might need to replace, depending on your config)

require 'fileutils'
include FileUtils::Verbose

infile = ARGV[0]
title = File.basename(infile,'.taskpaper').upcase
output = "# #{title} #\n\n"
prevlevel = 0
begin
    file = File.new(infile, "r")
    while (line = file.gets)
      if line =~ /^(\t+)?(.*?):(?:\s+)?$/
        tabs = $1
        project = $2
        if tabs.nil?
          output += "\n## #{project} ##\n\n"
          prevlevel = 0
        else
          output += "#{tabs.gsub(/^\t/,'')}* **#{project}**\n"
          prevlevel = tabs.length
        end
      elsif line =~ /^(\t+)?\- (.*)$/
        task = $2
        tabs = $1.nil? ? '' : $1
        task = "*#{task}*" if task =~ /@done/
        if tabs.length - prevlevel > 1
          tabs = "\t"
          prevlevel.times {|i| tabs += "\t"}
        end
        tabs = '' if prevlevel == 0 && tabs.length > 1
        output += "#{tabs.gsub(/^\t/,'')}* #{task.strip}\n"
        prevlevel = tabs.length
      else
        next if line =~ /^\s*$/
        tabs = ""
        prevlevel-1.times {|i| tabs += "\t"}
        output += "#{tabs}> #{line.strip}\n\n"
      end
    end
    file.close
rescue => err
    puts "Exception: #{err}"
    err
end

puts output