3 ms·
> As far as I know it's not possible to get this functionality in Haskell even with clever instance magic It is possible to fill in basic function bodies based
by Iceland_jack 2y ago
> As far as I know it's not possible to get this functionality in Haskell even with clever instance magic
It is possible to fill in basic function bodies based on their type, using ghc-justdoit (https://hackage.haskell.org/package/ghc-justdoit https://hackage.haskell.org/package/ghc-justdoit). That's maybe not what you meant, if you are looking for integrating pointfree into Haskell it can be added to ghci or your development environment.
foo :: ((a -> r) -> r) -> (a -> ((b -> r) -> r)) -> ((b -> r) -> r)
foo = (…)
In this case I wrote it because I knew about the pattern. Your lift definition is just ($)
flip \a -> ($ a)
= flip (&)
= flip (flip ($))
= ($)
- Iceland_jack 2y agoMaybe you meant to write (??) :: Functor f => f (a -> b) -> a -> f b funs ?? a = fmap ($ a) funs from lens: https://hackage.haskell.org/package/lens-5.3.2/docs/Control-Lens-Lens.html#v:-63--63- https://hackage.haskell.org/package/lens-5.3.2/docs/Control-... This is valid definition of lift along a different, less interesting but more general axis. lift = (??) @[]