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2020-11-26 07:46:55 → n0042 joins (d055ed89@208.85.237.137)
2020-11-26 07:47:07 <MarcelineVQ> what would cale do
2020-11-26 07:47:25 <asheshambasta> Anyone with more reflex experience than I can tell me why this traces: https://github.com/asheshambasta/flowerpower/blob/showcase/servant-reflex-dependency/fht-frontend/src/Frontend/Garden/Plant.hs#L93 while this doesn't: https://github.com/asheshambasta/flowerpower/blob/showcase/servant-reflex-dependency/fht-frontend/src/Frontend/Garden/Plant.hs#L103 (I couldn't provide a more minimal repro. of this)
2020-11-26 07:47:59 <jle`> looks like `traverse sequence`
2020-11-26 07:48:44 <dminuoso> traverse (sequence . swap)
2020-11-26 07:48:50 <koz_> :t traverse sequence
2020-11-26 07:48:51 <lambdabot> (Traversable t1, Traversable t2, Monad f) => t1 (t2 (f a)) -> f (t1 (t2 a))
2020-11-26 07:48:54 <dminuoso> % :t traverse (sequence . swap
2020-11-26 07:48:54 <yahb> dminuoso: ; <interactive>:1:26: error: parse error (possibly incorrect indentation or mismatched brackets)
2020-11-26 07:48:56 <dminuoso> % :t traverse (sequence . swap)
2020-11-26 07:48:56 <yahb> dminuoso: forall {t :: * -> *} {f :: * -> *} {a} {b}. (Traversable t, Monad f) => t (f a, b) -> f (t (b, a))
2020-11-26 07:49:12 <dminuoso> Oh, no. Actually traverse sequence right
2020-11-26 07:50:07 <jle`> traverse (sequence . swap . swap)
2020-11-26 07:50:28 <dminuoso> :)
2020-11-26 07:50:33 × gioyik quits (~gioyik@186.118.238.251) (Quit: WeeChat 3.0)
2020-11-26 07:51:26 × robotmay quits (~beepboop@80.172.187.81.in-addr.arpa) (Remote host closed the connection)
2020-11-26 07:51:40 <dminuoso> traverse (sequence . swap . flip const id . swap)
2020-11-26 07:52:15 <dminuoso> Bet hlint cant figure that one out.
2020-11-26 07:52:33 <koz_> :t flip const id
2020-11-26 07:52:34 <lambdabot> c -> c
2020-11-26 07:52:39 <koz_> Lol.
2020-11-26 07:52:55 <jle`> :t const id ()
2020-11-26 07:52:56 <lambdabot> a -> a
2020-11-26 07:53:47 × heatsink quits (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net) (Remote host closed the connection)
2020-11-26 07:54:02 <incertia> i had to think about flip const id for a bit
2020-11-26 07:54:22 <dminuoso> Well you can put something more interesting into `id`, that is better for tripping you up
2020-11-26 07:54:25 <dminuoso> like `flip const fmap`
2020-11-26 07:54:48 <jle`> :t const id id
2020-11-26 07:54:49 <lambdabot> a -> a
2020-11-26 07:54:58 → robotmay joins (~beepboop@2001:8b0:7af0:2580:888:72a9:4a8e:aea0)
2020-11-26 07:55:04 <dminuoso> % :t flip const fmap
2020-11-26 07:55:05 <yahb> dminuoso: ; <interactive>:1:12: error:; * Ambiguous type variable `f0' arising from a use of `fmap'; prevents the constraint `(Functor f0)' from being solved.; Probable fix: use a type annotation to specify what `f0' should be.; These potential instances exist:; instance [safe] forall a. Functor (Q.Fun a) -- Defined in `Test.QuickCheck.Function'; instance [safe] Functor Q.Gen
2020-11-26 07:55:12 <dminuoso> Oh. wait what?
2020-11-26 07:55:20 <jle`> it doesn't know what Functor instance to compile there
2020-11-26 07:55:31 <jle`> :t flip const map
2020-11-26 07:55:33 <lambdabot> c -> c
2020-11-26 07:55:46 <dminuoso> Oh I guess this would need impredicative types?
2020-11-26 07:56:01 <incertia> asheshambasta: i would imagine it wouldn't get traced if dEitherPlant is Left
2020-11-26 07:56:08 <dminuoso> yeah `flip const map` it is
2020-11-26 07:56:15 → sdx23 joins (~sdx23@unaffiliated/sdx23)
2020-11-26 07:56:16 <incertia> could be wrong here
2020-11-26 07:56:18 <jle`> flip const map itself only works because of defaulting i think
2020-11-26 07:56:30 <dminuoso> Why defaulting?
2020-11-26 07:56:33 <dminuoso> % :t flip const
2020-11-26 07:56:34 <yahb> dminuoso: forall {b} {c}. b -> c -> c
2020-11-26 07:56:43 <jle`> because it defaults to map :: (() -> ()) -> [()] -> [()]
2020-11-26 07:56:44 → raichoo joins (~raichoo@dslb-092-073-219-149.092.073.pools.vodafone-ip.de)
2020-11-26 07:56:58 <jle`> otherwise it wouldn't know what to pick for a and b
2020-11-26 07:56:59 <jle`> :t map
2020-11-26 07:57:00 <dminuoso> Ah, I see. Otherwise that would have required impredicativity
2020-11-26 07:57:01 <lambdabot> (a -> b) -> [a] -> [b]
2020-11-26 07:57:26 <incertia> in particular if any of eName or eDayPlanted are Left it would cause fst <$> maints/snd <$> maints to not be evaluated and thus not trigger the traceEvent
2020-11-26 07:57:28 <incertia> but im no guru
2020-11-26 07:57:34 <jle`> there should be defaulting for * -> *'s
2020-11-26 07:57:53 × Varis quits (~Tadas@unaffiliated/varis) (Remote host closed the connection)
2020-11-26 07:58:00 <dminuoso> You should open an issue on gitlab about that. Name `flip const fmap` as the motivating example.
2020-11-26 07:58:12 dminuoso smiles
2020-11-26 07:58:13 <jle`> bites me every day :)
2020-11-26 07:58:24 <jle`> i wonder what the default should be
2020-11-26 07:58:34 <jle`> maybe Identity first?
2020-11-26 07:58:41 <jle`> or maybe Proxy
2020-11-26 07:58:48 <jle`> ah yeah, Proxy first, then Identity
2020-11-26 07:59:17 <jle`> this would be my dream haskell
2020-11-26 07:59:54 <incertia> when i learned about Proxy my entire world changed
2020-11-26 07:59:57 <koz_> :t flip const map
2020-11-26 07:59:59 <lambdabot> c -> c
2020-11-26 08:00:03 <koz_> LOL
2020-11-26 08:00:18 → cfricke joins (~cfricke@unaffiliated/cfricke)
2020-11-26 08:00:26 <dminuoso> I think I should get three points for tripping koz_ up twice in a row.
2020-11-26 08:00:40 <incertia> that and DataKinds
2020-11-26 08:00:46 <incertia> it's so galaxy brained
2020-11-26 08:00:59 <xerox_> % :t flip const unsafePerformIO
2020-11-26 08:00:59 <yahb> xerox_: forall {c}. c -> c
2020-11-26 08:01:07 <koz_> incertia: Type :: Type is the real galaxy brain idea.
2020-11-26 08:01:19 <dminuoso> xerox_: Oh I have an idea.
2020-11-26 08:01:24 <dminuoso> flip const unsafeCoerce
2020-11-26 08:01:35 <koz_> :t flip const unsafeCoerce
2020-11-26 08:01:37 <lambdabot> error: Variable not in scope: unsafeCoerce
2020-11-26 08:01:46 × acowley quits (~acowley@c-68-83-22-43.hsd1.nj.comcast.net) (Read error: Connection reset by peer)
2020-11-26 08:01:47 <dminuoso> % import Unsafe.Coerce
2020-11-26 08:01:47 <yahb> dminuoso:
2020-11-26 08:01:52 <dminuoso> % :t flip const unsafeCoerce
2020-11-26 08:01:52 <yahb> dminuoso: forall {c}. c -> c
2020-11-26 08:01:55 <dminuoso> This looks really dangerous.
2020-11-26 08:02:17 → Varis joins (~Tadas@unaffiliated/varis)
2020-11-26 08:02:28 <jle`> `flip const unsafeCoerce` is pretty much the same as `unsafeCoerce`, ironically
2020-11-26 08:02:33 <jle`> just with a more specialized type
2020-11-26 08:02:42 <dminuoso> Okay enough of flip const. What other elaborate ways of doing.. nothing can you think of?
2020-11-26 08:02:50 × vg quits (~vg@139.59.59.230) (Quit: vg)
2020-11-26 08:03:01 <jle`> % map ($ 10) [unsafeCoerce, flip const unsafeCoerce]
2020-11-26 08:03:01 <koz_> dminuoso: fmap id
2020-11-26 08:03:01 <yahb> jle`: ; <interactive>:92:1: error:; Ambiguous occurrence `map'; It could refer to; either `Data.List.NonEmpty.map', imported from `Data.List.NonEmpty'; or `Prelude.map', imported from `Prelude' (and originally defined in `GHC.Base')
2020-11-26 08:03:06 → vg joins (~vg@139.59.59.230)
2020-11-26 08:03:10 <jle`> D:
2020-11-26 08:03:15 <koz_> dimap id id also works
2020-11-26 08:03:16 <jle`> % Prelude.map ($ 10) [unsafeCoerce, flip const unsafeCoerce]
2020-11-26 08:03:17 <yahb> jle`: [10,10]
2020-11-26 08:03:28 × vg quits (~vg@139.59.59.230) (Remote host closed the connection)
2020-11-26 08:03:28 <dminuoso> koz_: well those are very obvious
2020-11-26 08:03:28 <jle`> koz_: you mean dimap id id id
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