Channels
#arrow-contributors
- r
raulraja
03/09/2019, 1:25 PMthat is awesome, this is gonna be great for Arrow - s
sam
03/09/2019, 1:25 PMThe @higherkinded GenOf goes over my head though, so I will just add that on faith 😂 - r
raulraja
03/09/2019, 1:25 PMhahha yeah if you are interested it's not that complex https://arrow-kt.io/docs/patterns/glossary/#higher-kinds - s
sam
03/09/2019, 1:26 PM@LeoColman job for us ^^ - r
raulraja
03/09/2019, 1:26 PMit's a way to cheat Kotlin to enable higher kinded types - s
sam
03/09/2019, 1:26 PMI thought a higher kinded type wasA<B<C>>> - p
pakoito
03/09/2019, 1:27 PMyes, for A and B being generics - p
pakoito
03/09/2019, 1:27 PMkotlin won’t allow to describe them that way - s
sam
03/09/2019, 1:27 PMIs that not supported by kotlin ? - s
sam
03/09/2019, 1:27 PMreally? - p
pakoito
03/09/2019, 1:27 PMso we use an interface marker for it - p
pakoito
03/09/2019, 1:27 PMfun <A, B, C> bla(): A<B<C>> - p
pakoito
03/09/2019, 1:27 PMwon’t compile - s
sam
03/09/2019, 1:28 PMWow you're right - p
pakoito
03/09/2019, 1:28 PMfun <A, B, C> bla(): Kind<A, Kind<B, C>> - p
pakoito
03/09/2019, 1:28 PMthat does - s
sam
03/09/2019, 1:28 PMShows how little Kotlin I actually write - s
sam
03/09/2019, 1:28 PMMy day job is still Scala - p
pakoito
03/09/2019, 1:28 PMye, so for us to enable all that jazz we need to wrap in these interfaces, and do some safe downcasting - s
sam
03/09/2019, 1:29 PMI see, very clever, kind of like shapeless with it's HLists - p
pakoito
03/09/2019, 1:29 PMso for us to define typeclasses over Gen and so in a good way, we need for it to implementKind<ForGen, A> - r
raulraja
03/09/2019, 1:29 PMyeah, it's based on a paper about defunctionalization to enable kinds in type systems like Kotlins or Java's - p
pakoito
03/09/2019, 1:29 PM
is a witness, the marker we specialize on for downcastingForGen - r
raulraja
03/09/2019, 1:29 PMyou can do this in Java - s
sam
03/09/2019, 1:30 PMAmazing - s
sam
03/09/2019, 1:30 PMOk so we'll add that as well - s
sam
03/09/2019, 1:30 PMDoes someone who really knows what they're doing want to make a PR ? - s
sam
03/09/2019, 1:30 PMI'm going to release 3.3.2 soon and it can go in that - r
raulraja
03/09/2019, 1:30 PMthat'd be awesome, we just released 0.9.0 silently - r
raulraja
03/09/2019, 1:30 PMplease depend on that version