# File lib/facet/filelist.rb, line 149
  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