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2020-10-21 12:20:14 × Stanley00 quits (~stanley00@unaffiliated/stanley00) ()
2020-10-21 12:20:41 <[exa]> ixlun: anyway, your composed function has 2 parameters, which in the type here have types 'a1' and 'a2'.
2020-10-21 12:20:45 ski thought that wasn't too bad
2020-10-21 12:20:46 <geekosaur> this is a ghc-specific chaneg from standard Haskell, which is why the wikibook doesn't tlk about it
2020-10-21 12:22:02 → kyprizel joins (~kyprizel@185.204.1.185)
2020-10-21 12:22:14 <ski> iMonad : for the time being, if you don't want to bother with it right now, you could just make empty instances
2020-10-21 12:22:22 × coot quits (~coot@37.30.49.141.nat.umts.dynamic.t-mobile.pl) (Ping timeout: 260 seconds)
2020-10-21 12:23:02 <ski> instance Monad m => Functor (MaybeT m)
2020-10-21 12:23:04 <ski> where
2020-10-21 12:23:11 <ski> fmap = liftM
2020-10-21 12:23:23 <ski> instance Monad m => Applicative (MaybeT m)
2020-10-21 12:23:25 <ski> where
2020-10-21 12:23:29 <ski> pure = return
2020-10-21 12:23:34 <ski> (<*>) = ap
2020-10-21 12:23:38 × heatsink quits (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net) (Ping timeout: 265 seconds)
2020-10-21 12:23:49 <ski> would also work, as default implementations, in terms of your `Monad' instance
2020-10-21 12:24:36 × coot_ quits (~coot@37.30.51.114.nat.umts.dynamic.t-mobile.pl) (Ping timeout: 265 seconds)
2020-10-21 12:24:55 <ski> (however, it would be better to have `Functor f => Functor (MaybeT f)' and `Applicative i => Applicative (MaybeT i)'. but that requires you to do the work of actually implementing those instances "properly", rather than just deferring to the `Monad' instance)
2020-10-21 12:24:59 <ski> iMonad ^
2020-10-21 12:25:43 <ski> (to clarify, by "empty instances", i mean just skipping the `where', and the method implementation(s) after it)
2020-10-21 12:27:09 <iMonad> @ski what is "ap" comes from ?
2020-10-21 12:27:09 <lambdabot> Maybe you meant: wiki src ask
2020-10-21 12:27:23 × nicknick quits (75d746c7@117.215.70.199) (Remote host closed the connection)
2020-10-21 12:27:30 <iMonad> My ghc complain that is not in scope
2020-10-21 12:27:34 <ski> @index ap
2020-10-21 12:27:35 <lambdabot> Control.Monad
2020-10-21 12:27:56 <ski> it (and `liftM') is defined in terms of `return' and `(>>=)'
2020-10-21 12:27:58 hackage haskoin-store-data 0.38.0 - Data for Haskoin Store https://hackage.haskell.org/package/haskoin-store-data-0.38.0 (jprupp)
2020-10-21 12:28:09 → da39a3ee5e6b4b0d joins (~textual@n11211935170.netvigator.com)
2020-10-21 12:28:28 <ski> so, by defining `(<*>)' as `ap', that makes it call your `return' and `(>>=)' implementations, in your `Monad (MaybeT m)' instance
2020-10-21 12:28:37 <iMonad> Oh, it works
2020-10-21 12:28:57 hackage haskoin-store 0.38.0 - Storage and index for Bitcoin and Bitcoin Cash https://hackage.haskell.org/package/haskoin-store-0.38.0 (jprupp)
2020-10-21 12:29:01 × nbloomf quits (~nbloomf@2600:1700:ad14:3020:6cd0:22a:1738:5d24) (Quit: Textual IRC Client: www.textualapp.com)
2020-10-21 12:29:07 <ski> iMonad : now for `(>>=)' ?
2020-10-21 12:29:26 × taurux quits (~taurux@net-188-216-37-204.cust.vodafonedsl.it) (Ping timeout: 265 seconds)
2020-10-21 12:30:19 <iMonad> wiki example works
2020-10-21 12:30:24 <ixlun> Out of interest, what's people's opinion on what's better: `foo . bar . baz $ a' or `foo $ bar $ baz a'?
2020-10-21 12:30:51 → cods joins (~fred@tuxee.net)
2020-10-21 12:30:57 <merijn> ixlun: THe former is better
2020-10-21 12:30:58 <ski> ixlun : the former
2020-10-21 12:30:58 <geekosaur> the former
2020-10-21 12:31:08 <merijn> Because repeated . is more easily refactored
2020-10-21 12:31:12 × cods quits (~fred@tuxee.net) (Changing host)
2020-10-21 12:31:12 → cods joins (~fred@unaffiliated/cods)
2020-10-21 12:31:16 <ski> ixlun : or `(foo . bar . baz) a' or `foo (bar (baz a))'
2020-10-21 12:31:24 → taurux joins (~taurux@net-188-218-229-119.cust.vodafonedsl.it)
2020-10-21 12:31:36 <ski> (i'd prefer any of those three, to the latter you mentioned)
2020-10-21 12:31:41 <iMonad> if i understand correctly, monad transformer is just combine multiple monad into single one
2020-10-21 12:32:15 <ski> iMonad : it takes a(ny) monad and adds another (specific) "monad capability" to it
2020-10-21 12:32:40 <ski> (it does not combine any two arbitrary monads)
2020-10-21 12:33:03 <ixlun> Cool, I'll start to write in that method - coming from an imperative background it takes a while to rewire the brain!
2020-10-21 12:33:19 <ski> it does, but it's worth it :)
2020-10-21 12:34:00 <ski> it's only to expected that learning a new programming paradigm takes more time than learning yet another language in a paradigm one knows. it's a bit more like learning to program from scratch all over again
2020-10-21 12:35:03 <iMonad> @ski thanks for you explanation
2020-10-21 12:35:03 <lambdabot> Maybe you meant: wiki src ask
2020-10-21 12:35:03 <ski> (imho it helps to set aside what you know abour programming, so far. you can compare later, when you have some more solid foundations under your belt. unlearning old habits and trains of thought can take time / be tricky)
2020-10-21 12:36:15 <ski> iMonad : no problem :)
2020-10-21 12:36:19 <iMonad> but why we need to instance other types here ? it is not enouth to just instance a monad ?
2020-10-21 12:36:21 → Iwawa joins (~mdomin45@cpe-24-211-129-187.nc.res.rr.com)
2020-10-21 12:36:35 <ixlun> ski: agreed - that's why I think so far I've enjoyed learning Haskell more than another language. It's a completely new way to think about things
2020-10-21 12:36:58 <ski> because the type class `Monad' was changed to have `Applicative' as superclass. so every instance of `Monad' is required to already be an instance of `Applicative' (which in turn requires `Functor')
2020-10-21 12:37:25 <ski> however (as you saw), it's possible to use default implementations of `Applicative' (and `Functor') in terms of the `Monad' instance you're writing
2020-10-21 12:38:08 × geowiesnot quits (~user@i15-les02-ix2-87-89-181-157.sfr.lns.abo.bbox.fr) (Ping timeout: 265 seconds)
2020-10-21 12:38:16 <ski> (if one only wants to write an `Applicative' instance, where `Monad' is undesirable or not sensible, one can use `fmap = liftA' for the `Functor' instance, to make it defer to the `Applicative' instance, instead)
2020-10-21 12:38:28 → xerox_ joins (~xerox@unaffiliated/xerox)
2020-10-21 12:39:54 × Pitaya quits (~mdomin45@cpe-24-211-129-187.nc.res.rr.com) (Ping timeout: 260 seconds)
2020-10-21 12:40:04 → Lowl3v3l joins (~Lowl3v3l@dslb-002-203-195-108.002.203.pools.vodafone-ip.de)
2020-10-21 12:40:31 <ixlun> I've always found that the best way to learn something new is to write it too, I'm not one for reading a whole book and then diving in.
2020-10-21 12:40:42 <ixlun> I like to learn as I go
2020-10-21 12:40:45 Guest88073 is now known as lep-delete
2020-10-21 12:41:18 <ski> iMonad : btw, fwiw, it's not IRC convention/custom to adorn nicknames by sigils (like `@'). if you want to refer to, or address, someone, simply mention their nickname. in the latter case, e.g. by starting the message with the nickname, followed by a comma or a colon, and then the bulk of the message
2020-10-21 12:42:18 <iMonad> oh, sorry about that
2020-10-21 12:42:24 <iMonad> I am every new to irc
2020-10-21 12:42:33 <iMonad> *very*
2020-10-21 12:42:54 → mirrorbird joins (~psutcliff@2a00:801:42b:7891:16b1:e53f:55b2:15e1)
2020-10-21 12:42:56 <ski> many IRC clients will highlight/alert the user, in case their nickname is mentioned, first thing in a message. (not as many will, i think, highlight when it's mentioned anywhere else in a message). so, if you place `@' in front, then the nickname is not the first thing, and highlight might not happen
2020-10-21 12:43:27 → nineonin_ joins (~textual@216-19-190-182.dyn.novuscom.net)
2020-10-21 12:43:40 <ski> (also, `@' means something else, on IRC, namely that someone is a channel operator. however, i'd not suggest referring to operators by prefixing their names by `@', either)
2020-10-21 12:43:48 <ski> iMonad : no worry, just informing you
2020-10-21 12:44:24 → heatsink joins (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net)
2020-10-21 12:44:32 × ericsagnes quits (~ericsagne@2405:6580:0:5100:a175:4dc7:93af:b055) (Ping timeout: 260 seconds)
2020-10-21 12:44:44 × nineonin_ quits (~textual@216-19-190-182.dyn.novuscom.net) (Client Quit)
2020-10-21 12:45:19 <ixlun> Where would people suggest is the best place to look for critique on a project that I'm writing?
2020-10-21 12:46:41 <[exa]> ixlun: users! :D
2020-10-21 12:46:42 → cr3 joins (~cr3@192-222-143-195.qc.cable.ebox.net)
2020-10-21 12:47:35 <[exa]> ixlun: nevermind users, if you can extract something short enough, kindof self-contained, and pastebin it, you can get a lot of feedback from #haskell
2020-10-21 12:47:36 → cristi joins (~cristi@82.76.158.82)
2020-10-21 12:48:30 × ski quits (~ski@nc-2504-30.studat.chalmers.se) (Ping timeout: 260 seconds)
2020-10-21 12:48:51 × cristi quits (~cristi@82.76.158.82) (Remote host closed the connection)
2020-10-21 12:49:14 × heatsink quits (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net) (Ping timeout: 260 seconds)
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2020-10-21 12:51:00 × notnatebtw quits (~nate@110.138.18.157) (Quit: WeeChat 2.9)
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2020-10-21 12:53:48 × stefan-__ quits (~cri@42dots.de) (Read error: Connection reset by peer)
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2020-10-21 12:56:37 × GyroW_ quits (~GyroW@unaffiliated/gyrow) (Quit: Someone ate my pie)
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