[Haskell-cafe] What did you/do you find hard/dislike about Opaleye?

[Tom Ellis]

On Tue, Oct 25, 2016 at 12:49:13PM +0100, Oliver Charles wrote:
> On Mon, Oct 24, 2016 at 11:06 PM, Tom Ellis <
> tom-lists-haskell-cafe-2013 at jaguarpaw.co.uk> wrote:
> 
> > I'm planning to update and refresh Opaleye's documentation and add some new
> > functionality for common use cases. To help with this I'd like to request
> > input from anyone who has ever tried the library.
> >
> > Specifically, what do you (or did you) find hard about using Opaleye and
> > what did you dislike about it? If you tried it and gave up, what was the
> > major sticking point?
> 
> I dislike the whole `Default` type class stuff and have a very hard time
> reasoning about what is going on behind it. I understand it's basically
> creating "n-ary structures" (the description is as vague as my
> understanding), but I still struggle with it.

Hi Ollie,

Thanks for the feedback.  Have you read the "Default Explanation" document?

    https://github.com/tomjaguarpaw/haskell-opaleye/blob/master/Doc/Tutorial/DefaultExplanation.lhs

Does that help you understand what's going on behind Default?  Is there
still something missing that could help your understanding?

Tom