GHC's error messages are too verbose?

Neil Mitchell ndmitchell at
Sat Apr 14 06:40:26 EDT 2007


> I've long wondered why GHC issues such prolix error messages when it
> runs into a problem.

I am primarily a Hugs user, compiling and running only with GHC once
the code works, and only if I really need the speed - which is quite
rare. but I've been hacking a project in GHCi recently (requiring
template haskell), and I found the GHC error messages way too verbose.

> Compilers for other languages seem content with as little as one line of
> output per error (which I am not advocating), or a few lines of source
> with the problem highlighted, but I rarely see more.  Hugs also tends
> towards the terse side, but I've never found this to be a problem.

The most important thing in an error message for me is the line
number. Next I want to see the type of error - syntax, type, instance
etc. Then I want to see just a few lexemes of context so I can find
where to start looking. If after all that I didn't figure out where
the error was, I'd want more context - but I rarely want it with Hugs.

I much prefer the Hugs error messages, although this may be experience
with Hugs, rather than an issue with GHC.



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