What caught me off guard were the error messages when not enabling serde functionality for optional dependent crates (e.g. chrono). Nom, which I love, has been

What caught me off guard were the error messages when not enabling serde functionality for optional dependent crates (e.g. chrono). Nom, which I love, has been a matter of interpreting the error messages with a divining rod though. Emphasizing which part of the tuple didn't match up would be a big win, but IMO it should be pulled out and mentioned first. Highlighting could get lost in the noise (moreso without all the ANSI escape codes if you're redirecting output or whatnot).