class Rake::FileList

def calculate_exclude_regexp
  ignores = []
  @exclude_patterns.each do |pat|
    case pat
    when Regexp
      ignores << pat
    when /[*?]/
      Dir[pat].each do |p| ignores << p end
    else
      ignores << Regexp.quote(pat)
    end
  end
  if ignores.empty?
    @exclude_re = /^$/
  else
    re_str = ignores.collect { |p| "(" + p.to_s + ")" }.join("|")
    @exclude_re = Regexp.new(re_str)
  end
end