File tree crawler example.

killCRLF.rb

#!/usr/bin/ruby

class WalkDirTree
  def each_file(&block)
    raise ArgumentError unless block_given?
    @each_file = block
  end

  def walk!(dir='.')
    current_directory = Dir.pwd
    Dir.chdir(dir)

    Dir.glob('*').each do |f|
      if File.directory?(f)
        walk!(f)
      else
        if @each_file
          @each_file.call(current_directory + '/' + dir + '/' + f)
        end
      end
    end

    Dir.chdir(current_directory)
  end
end

# Example usage: translate CRLF's to just LF!
walker = WalkDirTree.new
walker.each_file do |filename|
  file = File.read(filename)
  File.open(filename, 'w') do |fh|
    fh.write(file.gsub(/\r?\n/,"\n"))
  end
end

walker.walk!