We need to add role annotations for 7.8

Brandon Allbery allbery.b at gmail.com
Fri Mar 14 13:00:28 UTC 2014

On Fri, Mar 14, 2014 at 5:36 AM, Johan Tibell <johan.tibell at gmail.com>wrote:

> I'm quite worried about this change though. I thought the default role for
> data type was nominal, as that's the safe default. If the default is
> representational, every package author will need to be aware of this
> feature and update their packages. That's quite a high cost.

Nominal default breaks everything that uses newtype deriving and doesn't
have role annotations, doesn't it? Representational default means things
behave in 7.8 as they did in earlier GHCs.

brandon s allbery kf8nh                               sine nomine associates
allbery.b at gmail.com                                  ballbery at sinenomine.net
unix, openafs, kerberos, infrastructure, xmonad        http://sinenomine.net
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