On 23/04/2014 20:04, dm-list-haskell-librar...@scs.stanford.edu wrote: > Edward Kmett <ekm...@gmail.com> writes: > >> You can wind up in perfectly legitimate situations where the name for the >> type you are working with isn't in scope, but where you can write a >> combinator that would infer to have that type. I'd hate to lose that. >> >> It is admittedly of marginal utility at first glance, but there are some >> tricks that actually need it, and it can also arise if a type synonym >> expands to a type that isn't exported or brought into scope, so trying to >> push this line of reasoning too far I is possibly not too productive. > > Good point. In particular, it's not weird at all want to export type > synonyms on their own, particularly where ghost type parameters are used > to select between only a few cases. Consider something like this > (inspired by postgresql-orm):
Is there an abstraction being protected by only exporting the type synonym in cases like this? Cheers, Ganesh _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
