Hello Markus,

On 2018-06-15 11:21, Markus Mottl <markus.mottl@gmail.com> writes:

> I don't think that you can currently do this.  According to the manual
> entry for GADTs: "This return type must use the same type constructor as
> the type being defined, and have the same number of parameters."
>
> But I guess it would be a supportable feature to perform type substitutions
> until the above is satisfied if at all possible.  Substituting manually is
> probably the only thing you can do until then.

Thank you for your reply. I'll use the explicit form for the moment with
some comments on the side.

Best,

Alan

-- 
OpenPGP Key ID : 040D0A3B4ED2E5C7
Monthly Athmospheric CO₂, Mauna Loa Obs. 2018-05: 411.25, 2017-05: 409.65