RFC: Adding support for an API-"since"-version-attribute to Haddock?

[Herbert Valerio Riedel]

"Bryan O'Sullivan" <bos at serpentine.com> writes:
> I think it would be very useful. We don't have any way of specifying
> identifier-level attributes right now that I know of, and such a capability
> would be helpful beyond just this use, too.

...what other use-cases for identifier-level attributes do you have in mind?