haddock, instances and defining modules

[Brent Yorgey]

On Thu, Oct 18, 2012 at 11:32:40AM +0200, Simon Hengel wrote:
> 
> It would still be nice if we had "source" links to instance definitions,
> and as a side effect they would also address this issue (you could then
> simply click on the "source" link to see where that instance is
> defined).

+1 for "source" links on instances!  I see there is already a ticket
for this:

  http://trac.haskell.org/haddock/ticket/145

but it is 2 years old.  I guess it just needs someone to actually code
it up.  How hard could it be?

...so I took myself up on my challenge and spent a half-hour source
diving in Haddock to try to figure out what would need to change in
order to support this feature.  I sketched out some notes which I
attached to the above ticket.  Anyone else should feel free to expand
on my notes or actually tackle implementing the feature!

-Brent