# File raggle, line 177
def uri?(str)
  uri_chars = "a-zA-Z0-9;\/?:@&=+$,_.!~*'()%-"  # see RFC 2396
  str =~ /^[a-zA-Z0-9]+:\/\/[#{uri_chars}]+/ or str =~ /^([#{uri_chars}]+?\.)*[#{uri_chars}]+?\.(com|org|net|us|au|uk)/ or str =~ /(\d{1,3}\.){3}\d{1,3}/
end