Re: TH changes for ghc 8.0

On Tue, Apr 12, 2016 at 02:22:23PM +1000, Erik de Castro Lopo wrote:

Date: Tue, 12 Apr 2016 14:22:23 +1000 From: Erik de Castro Lopo To: ghc-devs@haskell.org Subject: TH changes for ghc 8.0

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....

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`.

the docs say `cxt`, not `ctx`. not sure what that means either. (-: cheers, m.