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2020-11-11 06:23:27 × noecho quits (~noecho@2a01:4f8:1c0c:80ee::4223) (Quit: ZNC - http://znc.in)
2020-11-11 06:23:27 → knupfer joins (~Thunderbi@200116b82c3cbf007840659ab1a6a1ba.dip.versatel-1u1.de)
2020-11-11 06:23:55 → noecho joins (~noecho@static.143.42.203.116.clients.your-server.de)
2020-11-11 06:24:00 <Axman6> :t _1 Tagged
2020-11-11 06:24:01 <lambdabot> error:
2020-11-11 06:24:01 <lambdabot> Data constructor not in scope: Tagged :: a0 -> f b0
2020-11-11 06:24:08 × merijn quits (~merijn@83-160-49-249.ip.xs4all.nl) (Ping timeout: 272 seconds)
2020-11-11 06:24:12 <Axman6> % :t _1 Tagged
2020-11-11 06:24:13 <yahb> Axman6: ; <interactive>:1:4: error: Data constructor not in scope: Tagged :: a0 -> f b0
2020-11-11 06:24:30 → tromp joins (~tromp@dhcp-077-249-230-040.chello.nl)
2020-11-11 06:24:56 <Axman6> % import Data.Tagged
2020-11-11 06:24:57 <yahb> Axman6:
2020-11-11 06:24:59 <Axman6> % :t _1 Tagged
2020-11-11 06:24:59 <yahb> Axman6: forall {k} {s1} {t} {b} {s2 :: k}. Field1 s1 t b b => s1 -> Tagged s2 t
2020-11-11 06:25:44 → ensyde joins (~ensyde@99-185-235-117.lightspeed.chrlnc.sbcglobal.net)
2020-11-11 06:25:44 → takuan joins (~takuan@178-116-218-225.access.telenet.be)
2020-11-11 06:27:43 <bqv> how do i construct a half-simple prism
2020-11-11 06:27:54 <Axman6> "half-simple"?
2020-11-11 06:28:26 <bqv> looking for an optic that's a prismatic getter but identity setter
2020-11-11 06:28:51 <bqv> i'd suggest the type but i'm not sure on it
2020-11-11 06:28:56 <Axman6> sounds like you're out to break some laws bucko
2020-11-11 06:28:58 <jle`> what operations would it support?
2020-11-11 06:29:10 × tromp quits (~tromp@dhcp-077-249-230-040.chello.nl) (Ping timeout: 256 seconds)
2020-11-11 06:29:20 <bqv> well, the intention is to compose it with a lens i have already
2020-11-11 06:29:52 <jle`> what operations would you want the result of that composition to support?
2020-11-11 06:29:57 <bqv> that lens is a Lens (Maybe a) (Maybe b) (f (Maybe a)) (f (Maybe b))
2020-11-11 06:30:27 <bqv> get -> failable retrieval
2020-11-11 06:30:38 <bqv> set <- Maybe value
2020-11-11 06:30:58 <jle`> get :: Thing' s a -> s -> Maybe a ?
2020-11-11 06:31:02 × ensyde quits (~ensyde@99-185-235-117.lightspeed.chrlnc.sbcglobal.net) (Ping timeout: 265 seconds)
2020-11-11 06:31:07 <jle`> set :: ?
2020-11-11 06:31:56 <bqv> get :: Thing' s a -> s -> Maybe a, set :: Thing' s a -> Maybe a -> Thing' s a
2020-11-11 06:32:00 <bqv> (?)
2020-11-11 06:32:14 <bqv> wait
2020-11-11 06:32:36 <jle`> remember set for normal lenses is set :: Optic' s a -> a -> s -> s
2020-11-11 06:32:45 <bqv> yeah no, that's right. just, my current lens fits that, but the problem i'm trying to solve it getting it to behave sensibly with the ^? family of operations
2020-11-11 06:33:02 <jle`> do you have an example of a specific thing you want to do?
2020-11-11 06:33:41 → coot joins (~coot@37.30.49.253.nat.umts.dynamic.t-mobile.pl)
2020-11-11 06:35:37 <bqv> so with my current lens, i'll call it "focus": if i do ``inhabited ^.. focus._Just`` i get a list of one value, if i do ``uninhabited ^.. focus._Just`` i get an empty list. That's the get behaviour i'm after. if i do ``inhabited & focus .~ Just v`` the value is set to v, and if i do ``inhabited & focus .~ Nothing`` the value is cleared. That's the set behaviour i'm after
2020-11-11 06:35:51 → ensyde joins (~ensyde@99-185-235-117.lightspeed.chrlnc.sbcglobal.net)
2020-11-11 06:36:16 <bqv> focus :: IndexedLens' k (w (Maybe (k, a))) (Maybe a)
2020-11-11 06:37:05 × bitmapper quits (uid464869@gateway/web/irccloud.com/x-uttamgxxcsffgvha) (Quit: Connection closed for inactivity)
2020-11-11 06:38:02 → britva joins (~britva@31-10-157-156.cgn.dynamic.upc.ch)
2020-11-11 06:38:19 × britva quits (~britva@31-10-157-156.cgn.dynamic.upc.ch) (Client Quit)
2020-11-11 06:38:24 × knupfer quits (~Thunderbi@200116b82c3cbf007840659ab1a6a1ba.dip.versatel-1u1.de) (Ping timeout: 240 seconds)
2020-11-11 06:38:36 → britva joins (~britva@31-10-157-156.cgn.dynamic.upc.ch)
2020-11-11 06:39:19 <bqv> my current mental summary of what i want to acheive is lens composition of _Just, but only over the getter
2020-11-11 06:39:40 <bqv> that's an asymmetrical lens, but i think it's still a valid one
2020-11-11 06:39:49 <bqv> well, valid optic, at least
2020-11-11 06:40:03 <c_wraith> aren't you just describing exactly the behavior of at?
2020-11-11 06:40:18 <bqv> quite possibly, how would i use that here?
2020-11-11 06:40:34 <c_wraith> No idea, it was more that you can use it as a model for your type
2020-11-11 06:40:42 <c_wraith> > M.fromList [(1, "a"), (2, "q")] ^.. at 1 . _Just
2020-11-11 06:40:44 <lambdabot> ["a"]
2020-11-11 06:40:47 <c_wraith> > M.fromList [(1, "a"), (2, "q")] ^.. at 3 . _Just
2020-11-11 06:40:49 <lambdabot> []
2020-11-11 06:41:05 <c_wraith> > M.fromList [(1, "a"), (2, "q")] & at 1 .~ Just "hi"
2020-11-11 06:41:07 <lambdabot> fromList [(1,"hi"),(2,"q")]
2020-11-11 06:41:11 <c_wraith> > M.fromList [(1, "a"), (2, "q")] & at 1 .~ Nothing
2020-11-11 06:41:12 <lambdabot> fromList [(2,"q")]
2020-11-11 06:41:14 × ensyde quits (~ensyde@99-185-235-117.lightspeed.chrlnc.sbcglobal.net) (Ping timeout: 272 seconds)
2020-11-11 06:41:21 × Sheilong quits (uid293653@gateway/web/irccloud.com/x-jmssjdeibemlfomz) (Quit: Connection closed for inactivity)
2020-11-11 06:41:22 <c_wraith> I mean... that's the properties you want, right?
2020-11-11 06:41:39 <bqv> yes...
2020-11-11 06:41:45 <c_wraith> :t at
2020-11-11 06:41:46 <lambdabot> (At m, Functor f) => Index m -> (Maybe (IxValue m) -> f (Maybe (IxValue m))) -> m -> f m
2020-11-11 06:42:17 <bqv> :t at undefined
2020-11-11 06:42:18 <lambdabot> (At m, Functor f) => (Maybe (IxValue m) -> f (Maybe (IxValue m))) -> m -> f m
2020-11-11 06:42:44 <c_wraith> I mean, the class stuff is making that complicated for no reason
2020-11-11 06:43:02 <c_wraith> Strip that away, and you've got a type like Lens s t (Maybe a) (Maybe b)
2020-11-11 06:43:07 → thir joins (~thir@p200300f27f0b7e00894576386620b0d0.dip0.t-ipconnect.de)
2020-11-11 06:44:05 <c_wraith> or Lens' s (Maybe a) if you can't change types
2020-11-11 06:45:14 <bqv> see the frustrating part is that my current lens has that type
2020-11-11 06:45:34 <bqv> but then if i try ``inhabited ^.. focus`` i get [Just val] instead of [val]
2020-11-11 06:45:50 <bqv> so i feel like there's some constraint applied one functor too high or something
2020-11-11 06:45:52 <c_wraith> Oh, you want to skip the _Just part?
2020-11-11 06:45:58 <c_wraith> That's not going to work
2020-11-11 06:46:06 <bqv> oh
2020-11-11 06:46:27 → danvet joins (~Daniel@2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa)
2020-11-11 06:47:32 × thir quits (~thir@p200300f27f0b7e00894576386620b0d0.dip0.t-ipconnect.de) (Ping timeout: 260 seconds)
2020-11-11 06:47:53 <c_wraith> the problem there is that you can't have traversal-like behavior (skipping Nothing values with toListOf) at the same time as you have lens-like behavior (setting to Nothing to delete)
2020-11-11 06:48:27 <c_wraith> Nothing is either a target or it isn't. You can't have it both ways
2020-11-11 06:48:32 <bqv> ack, so this is logically impossible
2020-11-11 06:48:41 <bqv> half a day wasted..
2020-11-11 06:48:52 <bqv> so I suppose my best plan would be to separate the getter and setter, then
2020-11-11 06:49:38 <c_wraith> Or just use _Just when needed. But yes, separating them is certainly attested. lens has both the Ix and At classes to handle the traversal and lens cases
2020-11-11 06:50:13 <bqv> well, the problem is that the indexedlens's index cell is a partial function
2020-11-11 06:50:24 <bqv> so in the situation that the value is Nothing, the index is undefined
2020-11-11 06:50:28 <bqv> i was trying to avoid that
2020-11-11 06:50:49 → shutdown_-h_now joins (~arjan@2001:1c06:2d0b:2312:c3b:76:7192:2636)
2020-11-11 06:56:31 <bqv> ok nevermind, got this to with with some other form of type abuse
2020-11-11 06:56:34 × da39a3ee5e6b4b0d quits (~da39a3ee5@cm-171-98-69-111.revip7.asianet.co.th) (Ping timeout: 246 seconds)
2020-11-11 06:57:33 → da39a3ee5e6b4b0d joins (~da39a3ee5@cm-171-98-69-111.revip7.asianet.co.th)
2020-11-11 06:58:01 hackage uniqueness-periods-vector-examples 0.14.4.0 - Usage examples for the uniqueness-periods-vector series of packages https://hackage.haskell.org/package/uniqueness-periods-vector-examples-0.14.4.0 (OleksandrZhabenko)
2020-11-11 06:58:05 → merijn joins (~merijn@83-160-49-249.ip.xs4all.nl)
2020-11-11 07:02:52 × wroathe quits (~wroathe@c-68-54-25-135.hsd1.mn.comcast.net) (Quit: leaving)
2020-11-11 07:03:49 → Feuermagier_ joins (~Feuermagi@213.178.26.41)
2020-11-11 07:05:53 → alp joins (~alp@88.126.45.36)
2020-11-11 07:06:19 × Feuermagier quits (~Feuermagi@213.178.26.41) (Ping timeout: 265 seconds)
2020-11-11 07:06:32 → tenniscp25 joins (~tenniscp2@node-14js.pool-125-25.dynamic.totinternet.net)
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