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2021-04-13 11:50:31 <lambdabot> unexpected " "
2021-04-13 11:50:31 <lambdabot> expecting operator
2021-04-13 11:50:43 <alexm_> @pl "(<*>) fs xs = flatMap (<$> xs) fs"
2021-04-13 11:50:43 <lambdabot> "(<*>) fs xs = flatMap (<$> xs) fs"
2021-04-13 11:50:43 <ski> xerox_ : i wonder why that claims `unfoldTree' is breadth-first order ..
2021-04-13 11:51:14 <__monty__> @pl flatMap (<$> xs) fs
2021-04-13 11:51:14 <lambdabot> flatMap (<$> xs) fs
2021-04-13 11:51:24 <__monty__> alexm_: Can't pass a definition.
2021-04-13 11:51:36 <ski> @pl \fs xs -> flatMap (<$> xs) fs
2021-04-13 11:51:36 <lambdabot> flip (flatMap . flip (<$>))
2021-04-13 11:51:38 <alexm_> oops, cheers :)
2021-04-13 11:52:00 Mrbuck joins (~Mrbuck@gateway/tor-sasl/mrbuck)
2021-04-13 11:52:08 <ski> @pl doubleMap f g xs = map f (map g xs)
2021-04-13 11:52:08 <lambdabot> doubleMap = (. map) . (.) . map
2021-04-13 11:53:53 <__monty__> Oh, it does do definitions? Then why didn't the previous query work?
2021-04-13 11:54:10 <ski> @type \fs xs -> fs >>= (<$> xs)
2021-04-13 11:54:11 <lambdabot> Monad m => m (a -> b) -> m a -> m b
2021-04-13 11:54:14 <ski> @type ap
2021-04-13 11:54:15 <lambdabot> Monad m => m (a -> b) -> m a -> m b
2021-04-13 11:54:25 <ski> @src ap
2021-04-13 11:54:25 <lambdabot> ap = liftM2 id
2021-04-13 11:54:39 <ski> __monty__ : i guess it doesn't parse operator definitions ..
2021-04-13 11:54:55 <ski> alexm_ ^ ?
2021-04-13 11:55:13 <xerox_> ski: right?
2021-04-13 11:55:20 hololeap joins (~hololeap@gateway/tor-sasl/hololeap)
2021-04-13 11:55:30 <__monty__> @pl fs <*> xs = flatMap (<$> xs) fs
2021-04-13 11:55:31 <lambdabot> (line 1, column 12):
2021-04-13 11:55:31 <lambdabot> unexpected " "
2021-04-13 11:55:48 <ski> i mean, it doesn't really do any specifically depth-first vs. breadth-first stuff
2021-04-13 11:56:19 <dibblego> ski: there's a java RFE from 2001 with really long discussion — can't find it though
2021-04-13 11:57:04 <ski> > let nodes = 1 : [n | m <- nodes,n <- [2*m,2*m + 1]] in nodes -- unlike this, which does breadth-first
2021-04-13 11:57:06 <lambdabot> [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,...
2021-04-13 11:57:12 <ski> (only works for infinite trees, though)
2021-04-13 11:57:26 <ski> "Request For E???" ?
2021-04-13 11:57:50 frozenErebus joins (~frozenEre@37.231.244.249)
2021-04-13 11:57:58 <ski> dibblego : would be interested to take a look, if you find it later
2021-04-13 11:58:19 <dibblego> yeah, it's a shame I've lost it
2021-04-13 11:58:23 <alexm_> thanks ski
2021-04-13 11:58:30 hololeap_ joins (~hololeap@gateway/tor-sasl/hololeap)
2021-04-13 11:59:57 × hololeap quits (~hololeap@gateway/tor-sasl/hololeap) (Ping timeout: 240 seconds)
2021-04-13 12:01:32 urodna_ joins (~urodna@unaffiliated/urodna)
2021-04-13 12:02:09 LKoen_ joins (~LKoen@65.250.88.92.rev.sfr.net)
2021-04-13 12:02:36 <ski> @let infiniteSubtreesBreadthFirst :: Tree a -> [Tree a]; infiniteSubtreesBreadthFirst t = ts where ts = t : [t | t <- ts,t <- subForest t]
2021-04-13 12:02:37 <lambdabot> Defined.
2021-04-13 12:02:45 <ski> @type map rootLabel . infiniteSubtreesBreadthFirst
2021-04-13 12:02:47 <lambdabot> Tree b -> [b]
2021-04-13 12:03:26 × oish quits (~charlie@228.25.169.217.in-addr.arpa) (Quit: leaving)
2021-04-13 12:04:16 <ski> alexm_ : were you looking to define `(<*>)' for `Applicative', based on `(>>=)' in a `Monad' instance ?
2021-04-13 12:04:17 × todda7 quits (~torstein@ppp-2-85-110-156.home.otenet.gr) (Ping timeout: 260 seconds)
2021-04-13 12:04:34 × kini quits (~kini@unaffiliated/kini) (Remote host closed the connection)
2021-04-13 12:04:52 × LKoen quits (~LKoen@65.250.88.92.rev.sfr.net) (Ping timeout: 260 seconds)
2021-04-13 12:05:50 kini joins (~kini@unaffiliated/kini)
2021-04-13 12:06:28 × Mrbuck quits (~Mrbuck@gateway/tor-sasl/mrbuck) (Remote host closed the connection)
2021-04-13 12:07:14 Mrbuck joins (~Mrbuck@gateway/tor-sasl/mrbuck)
2021-04-13 12:07:37 <alexm_> ski: I am defining (<*>) for Applicative for the List type, it's just an exercise from fp-course (former NICTA)
2021-04-13 12:08:41 <dibblego> alexm_: did you do flatMap and map from List.hs ?
2021-04-13 12:08:42 <alexm_> in this case point free version looks less readable to me though
2021-04-13 12:09:06 × Mrbuck quits (~Mrbuck@gateway/tor-sasl/mrbuck) (Remote host closed the connection)
2021-04-13 12:09:18 <alexm_> dibblego yes, I did
2021-04-13 12:09:23 Deide joins (~Deide@217.155.19.23)
2021-04-13 12:09:33 <dibblego> alexm_: they will get you to (<*>) for List
2021-04-13 12:09:52 Mrbuck joins (~Mrbuck@gateway/tor-sasl/mrbuck)
2021-04-13 12:09:59 <alexm_> yeah, I figured applicative out already via flatMap, thanks :)
2021-04-13 12:10:06 <dibblego> when the course is run, we use type holes a lot
2021-04-13 12:10:11 <dibblego> ok cool
2021-04-13 12:10:22 <merijn> dibblego: type holes or typed holes? :p
2021-04-13 12:10:27 <merijn> (or both, I suppose)
2021-04-13 12:10:28 <alexm_> I was just playing around with the point free version of the definition
2021-04-13 12:10:38 <dibblego> _theseones
2021-04-13 12:11:12 <dibblego> I've been flying all arvo and night, tired, but leave questions if you have any — up early to fly home
2021-04-13 12:11:21 <merijn> dibblego: You are aware of -fdefer-typed-holes? (because sadly, every time I find out many people aren't :( )
2021-04-13 12:11:43 <dibblego> merijn: yes, the course material was written before those, so error is used instead (PR!?)
2021-04-13 12:13:03 × andreas303 quits (~andreas@gateway/tor-sasl/andreas303) (Remote host closed the connection)
2021-04-13 12:13:18 <alexm_> thanks dibblego
2021-04-13 12:13:24 <merijn> dibblego: Just trying to make sure my effort of hacking in that flag doesn't go to waste ;) It's my first and crowning contribution to Haskell, imo :p
2021-04-13 12:13:35 <dibblego> merijn: we use it in the course
2021-04-13 12:13:41 <merijn> \o/
2021-04-13 12:13:43 andreas303 joins (~andreas@gateway/tor-sasl/andreas303)
2021-04-13 12:14:01 <merijn> Immortality achieved!
2021-04-13 12:14:04 <alexm_> what this flag does in short?
2021-04-13 12:14:32 <merijn> alexm_: Makes typed holes behave like undefined, so you can run code without having to implement everything
2021-04-13 12:14:59 <merijn> The major advantage over undefined being: Better warnings and, once you disable the flag, you can't accidentally forget any undefined's in the source
2021-04-13 12:15:16 <merijn> Since they're compile errors without the flag (and undefined isn't)
2021-04-13 12:15:21 <alexm_> sweet
2021-04-13 12:17:50 <__monty__> xv
2021-04-13 12:18:46 todda7 joins (~torstein@athedsl-09242.home.otenet.gr)
2021-04-13 12:19:27 elfets joins (~elfets@ip-37-201-23-96.hsi13.unitymediagroup.de)
2021-04-13 12:29:48 kiweun joins (~kiweun@2607:fea8:2a62:9600:f0c8:b06a:abe0:d60)
2021-04-13 12:29:52 oo_miguel joins (~miguel@89-72-187-203.dynamic.chello.pl)
2021-04-13 12:32:39 ddk joins (9d2a7d60@157.42.125.96)
2021-04-13 12:33:12 <ddk> Hello all
2021-04-13 12:33:55 × ulidtko|k quits (~ulidtko@194.54.80.38) (Ping timeout: 252 seconds)
2021-04-13 12:34:05 <oo_miguel> Hello. I am using Network.HTTP.Client.Manager's managerModifyRequest and managerModifyResponse hooks to implement a simple logging middleware. Maybe I a missing something, but while I can easily check what URL a `Request` is related to, I do not see any such possibility inside the `Response` hook. Any suggestions please?
2021-04-13 12:34:22 × _bin quits (~bin@2600:1700:10a1:38d0:6924:8e26:a144:5b39) (Quit: ZNC - https://znc.in)
2021-04-13 12:34:24 × kiweun quits (~kiweun@2607:fea8:2a62:9600:f0c8:b06a:abe0:d60) (Ping timeout: 258 seconds)
2021-04-13 12:34:58 × kritzefitz quits (~kritzefit@212.86.56.80) (Ping timeout: 240 seconds)
2021-04-13 12:35:11 <ddk> I'm using postgres-simple, now I need timestamp in my program but I'm unsure which type to use in postgres which can be easily parsed between Haskell and postgres to and fro.
2021-04-13 12:35:34 <alexm_> @pl fa x $ fb x
2021-04-13 12:35:35 <lambdabot> fa x (fb x)
2021-04-13 12:36:47 <alexm_> @pl \fa fb x -> fa x $ fb x

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