Toward better syntax errors
Simon Peyton Jones
simonpj at microsoft.com
Tue Apr 7 22:11:07 UTC 2015
Thank Dan. I'm keen on better error messages.
If you want to change Happy, though, you need talk to Simon Marlow.
| -----Original Message-----
| From: ghc-devs [mailto:ghc-devs-bounces at haskell.org] On Behalf Of Dan
| Sent: 07 April 2015 21:34
| To: ghc-devs at haskell.org
| Subject: Toward better syntax errors
| Forwarded here is a link to a blog post I authored about improving
| GHC's syntax errors:
| In fact, this came about after I started using Happy more extensively,
| and at one point thought that GHC could benefit too
| The gist of it, is that it was relatively easy to reach an improvement
| such as follows (notice 'possible tokens' below):
| test i = case i of 2
| main = return ()
| example1.hs:2:1: parse error (possibly incorrect indentation or
| mismatched brackets), possible tokens: '|' '->'
| It spawned a more extensive discussion regarding type errors here:
| Following to that, it was suggested that a further discussion in the GHC
| dev mailing list can continue about this direction (syntax errors,
| type errors and whatnot).
| Dan Aloni
| ghc-devs mailing list
| ghc-devs at haskell.org
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