# File lib/rake.rb, line 951
951:     def calculate_exclude_regexp
952:       ignores = []
953:       @exclude_patterns.each do |pat|
954:         case pat
955:         when Regexp
956:           ignores << pat
957:         when /[*.]/
958:           Dir[pat].each do |p| ignores << p end
959:         else
960:           ignores << Regexp.quote(pat)
961:         end
962:       end
963:       if ignores.empty?
964:         @exclude_re = /^$/
965:       else
966:         re_str = ignores.collect { |p| "(" + p.to_s + ")" }.join("|")
967:         @exclude_re = Regexp.new(re_str)
968:       end
969:     end