TH changes for ghc 8.0

Tue Apr 12 04:22:23 UTC 2016

Hi all,

I'm working on updating persistent-template for ghc-8.0 and reading the
migration guide:

    https://ghc.haskell.org/trac/ghc/wiki/Migration/8.0#template-haskell-2.11.0.0

specifically the bit that says:

> * the DataD, NewtypeD, DataInstD, and NewtypeInstD constructors have a new
>   field `Maybe Kind` (#10828), and take a `CxtQ` instead of a `[Name]` for
>   the derived classes (#10819). If you don't know what to do, use `Nothing`
>   for the kind signature, and `cxt []` for the derived classes. 

Using `Nothing` as suggested is working out well enough, but I'm a bit befuddled
by the change from `[Name]` to `CtxQ` and the usage of `ctx []`. I can't seem to
find *any* function named `ctx`.

Any light people may be about to shed on this would be much appreciated.

Cheers,
Erik
-- 
----------------------------------------------------------------------
Erik de Castro Lopo
http://www.mega-nerd.com/