Preventing manual instances

Joachim Breitner mail at joachim-breitner.de
Mon Sep 9 07:25:01 UTC 2013


Dear Predro,

Am Sonntag, den 08.09.2013, 18:27 -0500 schrieb Austin Seipp:
> I know Pedro committed the work to make manual
> Typeable instances an error, which is great.

the Coercible class has a similar property, and I added the check to
prevent manual instances to checkValidInstance in TcValidity:
https://github.com/nomeata/ghc/commit/5e3f13
while you did it in tcInstDecls1 in TcInstDecls:
http://git.haskell.org/?p=ghc.git;a=commitdiff;h=5335e56953c4bbe18166039c06256e725f074b64

I’m happy to follow suite if you tell me that TcInstDecls is indeed the
better spot for such a check.

Greetings,
Joachim

-- 
Joachim “nomeata” Breitner
  mail at joachim-breitner.dehttp://www.joachim-breitner.de/
  Jabber: nomeata at joachim-breitner.de  • GPG-Key: 0x4743206C
  Debian Developer: nomeata at debian.org
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