Narrower (per-method) GND

[Joachim Breitner]

Hi,

just responding to this one aspect:

Am Sonntag, den 08.01.2017, 21:16 -0500 schrieb David Feuer:
> but using defaults for
> the others would give poor implementations. To cover this case, I
> think it would be nice to add per-method GND-deriving syntax. This
> could look something like
> 
> instance C T where
>   deriving f
>   g = ....

Assuming
  newtype T = MkT S

You can achieve this using

  instance C T where
     f = coerce (f @F)
     g = ....

(which is precisely what GND does), so I don’t think any new syntax is
needed here.

Greetings,
Joachim

-- 
Joachim “nomeata” Breitner
  mail at joachim-breitner.de • https://www.joachim-breitner.de/
  XMPP: nomeata at joachim-breitner.de • OpenPGP-Key: 0xF0FBF51F
  Debian Developer: nomeata at debian.org
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