Detect silly error with S.lines on a stream that is already lines.

[rrnewton]

Ok, I confess, I committed this silly error. No stream output ever emerges because it keeps accumulating an infinitely long line.

It might help to have a version of "lines" that at least throws an error if the line size gets over a certain length (or split after that length). Or perhaps there is some better way to help debug this silliness... I guess I kind of want a newtype for InputStream ByteStrings that represent lines (implicit newline) vs. those that don't.

[gregorycollins]

I am also not especially comfortable with the fact that there are functions like lines that can collect an unbounded amount of input. Probably lines should call lines' :: Int -> InputStream ByteString -> IO (InputStream ByteString) which stipulates a maximum line length.