cut_off

# File lib/rdoc/rd/block_parser.rb, line 282
def cut_off(src)
  ret = []
  whiteline_buf = []

  line = src.shift
  /^\s*/ =~ line

  indent = Regexp.quote($&)
  ret.push($')

  while line = src.shift
    if /^(\s*)$/ =~ line
      whiteline_buf.push(line)
    elsif /^#{indent}/ =~ line
      unless whiteline_buf.empty?
        ret.concat(whiteline_buf)
        whiteline_buf.clear
      end
      ret.push($')
    else
      raise "[BUG]: probably Parser Error while cutting off.\n"
    end
  end
  ret
end