It's just been brought to my attention that there's a small bug in the Network.URI code I wrote many years ago. I'll happily fix this, but I'm not sure what are the current mechanisms for accessing/updating the library repositories these days. Can anyone offer a pointer? (I've checked the error report against RFC 3986, and confirm that the proposed change seems correct. Ideally, there should be a test case for this.) Thanks to Eugen Kuksa for pointing this out. [[ In http://hackage.haskell.org/packages/archive/network/latest/doc/html/src/Netw... at ipvFuture :: URIParser String ipvFuture = do { char 'v' ; h <- hexDigitChar ; char '.' ; a <- many1 (satisfy isIpvFutureChar) ; return $ 'c':h:'.':a } there should be ; return $ 'v':h:'.':a ]] #g --