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2020-10-21 10:18:25 <merijn> It is, tbh, a rather inefficient way of doing things, but hey
2020-10-21 10:18:42 <ski> then, checking whether such a tail starts with the needle, amounts to checking whether they hay stack contains the needle somewhere
2020-10-21 10:19:55 × nineonin_ quits (~textual@216-19-190-182.dyn.novuscom.net) (Client Quit)
2020-10-21 10:22:25 <Echosolace> I need to play around some more.
2020-10-21 10:24:44 × michalrus quits (m@michalrus.com) (Ping timeout: 265 seconds)
2020-10-21 10:25:33 <Echosolace> If I have fruitlist = ["strawberry","green apple","red apple","apple granny"]
2020-10-21 10:25:45 <Echosolace> and I search for ["apple"]
2020-10-21 10:25:52 <Echosolace> I get False.
2020-10-21 10:26:13 <Echosolace> I think this is because:
2020-10-21 10:26:17 <Echosolace> take nlen x == needle
2020-10-21 10:26:37 <Echosolace> We are taking the length of needle's worth of element x...
2020-10-21 10:26:50 <Echosolace> But... I'm kinda surprised.
2020-10-21 10:27:07 <Echosolace> nlen of apple is 5.
2020-10-21 10:27:09 <merijn> Echosolace: That does a different thing
2020-10-21 10:27:13 <merijn> Echosolace: no
2020-10-21 10:27:16 <Echosolace> Oh...
2020-10-21 10:27:22 <merijn> Echosolace: Or rather, yes, but that's not what you're doing
2020-10-21 10:27:33 <merijn> You're taking the length of ["apple"], which is 1
2020-10-21 10:27:42 <Echosolace> Ah.
2020-10-21 10:27:48 <merijn> It's a list containing one string
2020-10-21 10:27:48 × stefan-__ quits (~cri@42dots.de) (Read error: Connection reset by peer)
2020-10-21 10:27:56 <Echosolace> Ok I need to go back and rethink a lot one sec.
2020-10-21 10:28:08 <merijn> and then you're checking if any of the strings in your other list match "apple" (to which the answer is "no")
2020-10-21 10:28:11 stefan-__ joins (~cri@42dots.de)
2020-10-21 10:28:19 × jol quits (~jol@jol.dev) (Ping timeout: 246 seconds)
2020-10-21 10:28:25 <merijn> Echosolace: Consider the type of search
2020-10-21 10:28:37 <merijn> "Eq a => [a] -> [a] -> Bool"
2020-10-21 10:28:50 <ski> @let search :: Eq a => [a] -> [a] -> Bool; search needle haystack = foldl (\acc x -> if take nlen x == needle then True else acc) False (tails haystack) where nlen = length needle
2020-10-21 10:28:50 <merijn> it's checking whether the first list appears inside the second one
2020-10-21 10:28:51 <lambdabot> Defined.
2020-10-21 10:28:53 × cristi_ quits (~cristi@82.76.158.82) (Quit: cristi_)
2020-10-21 10:28:58 × bartemius quits (~bartemius@109.252.19.142) (Remote host closed the connection)
2020-10-21 10:29:03 <merijn> Does the list ["apple"] occur inside your second list? No
2020-10-21 10:29:11 <ski> > search ["apple"] ["strawberry","green apple","red apple","apple granny"]
2020-10-21 10:29:12 × cyberlard quits (~cyberlard@unaffiliated/jludwig) (Ping timeout: 256 seconds)
2020-10-21 10:29:13 <lambdabot> False
2020-10-21 10:29:23 <ski> > search ["green apple"] ["strawberry","green apple","red apple","apple granny"]
2020-10-21 10:29:24 <Echosolace> I see that. Thanks.
2020-10-21 10:29:26 <lambdabot> True
2020-10-21 10:29:27 <merijn> Echosolace: 'search "apple" "apple granny"' otoh should work
2020-10-21 10:29:34 michalrus joins (m@michalrus.com)
2020-10-21 10:29:36 <ski> > search ["green apple","red apple"] ["strawberry","green apple","red apple","apple granny"]
2020-10-21 10:29:37 <lambdabot> True
2020-10-21 10:29:57 <ski> > search "apple" "apple granny"
2020-10-21 10:30:00 <lambdabot> True
2020-10-21 10:30:29 cyberlard joins (~cyberlard@unaffiliated/jludwig)
2020-10-21 10:30:43 <lortabac> idnar: if your purpose is running multiple actions concurrently you can use the Applicative instance of Concurrently
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2020-10-21 10:34:52 <Echosolace> Ok I've got that main function body figured out, but in the case of fruitlist = ["strawberry","apple","orange","banana"], I wonder if I search for apple why it wouldn't eventually return false, because after iterating to orange or banana, the accumulator would turn False.
2020-10-21 10:35:21 <Echosolace> Right?
2020-10-21 10:35:53 <Echosolace> Or wait...
2020-10-21 10:36:01 <Echosolace> Once it turns true it's always true.
2020-10-21 10:37:06 <Echosolace> I still don't see where tails haystack is called.
2020-10-21 10:37:12 <Echosolace> in foldl (\acc x -> if take nlen x == needle then True else acc) False (tails haystack)
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2020-10-21 10:40:52 × bliminse quits (~bliminse@host109-158-54-87.range109-158.btcentralplus.com) (Ping timeout: 272 seconds)
2020-10-21 10:40:52 <nicknick> Is there any bot here who can solve this?
2020-10-21 10:40:54 <nicknick> f :: Num a => a -> a -> a
2020-10-21 10:41:01 acidjnk_new2 joins (~acidjnk@p200300d0c7237831d40d0866fc0488e0.dip0.t-ipconnect.de)
2020-10-21 10:41:11 <nicknick> I need to convert f :: Num a => a -> a -> a to function.
2020-10-21 10:41:23 × alp quits (~alp@2a01:e0a:58b:4920:785c:23a0:93c6:f784) (Ping timeout: 272 seconds)
2020-10-21 10:41:36 <ski> f x y = x
2020-10-21 10:41:39 <ski> how about that ?
2020-10-21 10:42:06 <nicknick> What if it is more complex?
2020-10-21 10:42:07 <nicknick> f :: Num a => (a -> a -> a) -> a -> [a] -> [a]
2020-10-21 10:42:18 × heatsink quits (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net) (Ping timeout: 256 seconds)
2020-10-21 10:42:25 <ski> f _ _ _ = []
2020-10-21 10:42:52 <nicknick> Ikea rocks :)
2020-10-21 10:42:58 <nicknick> Are you God or a bot?
2020-10-21 10:43:05 <Echosolace> That's exactly what I was thinking.
2020-10-21 10:43:10 <ski> Echosolace : `tails haystack' is called in the last actual parameter of that `foldl' call
2020-10-21 10:43:26 <Echosolace> Right, I got that from my most recent error after deleting that segment.
2020-10-21 10:43:36 <Echosolace> Thanks.
2020-10-21 10:43:39 × babygnu quits (~robert@gateway/tor-sasl/babygnu) (Quit: Leaving)
2020-10-21 10:43:42 <ski> (it literally says `tails haystack', there)
2020-10-21 10:43:46 <Echosolace> >:t foldl
2020-10-21 10:43:52 <ski> @type foldl
2020-10-21 10:43:53 <lambdabot> Foldable t => (b -> a -> b) -> b -> t a -> b
2020-10-21 10:44:13 <Echosolace> Ok that I have major trouble understanding.
2020-10-21 10:44:14 <ski> @type foldl :: (s -> a -> s) -> s -> [a] -> s
2020-10-21 10:44:15 <lambdabot> (s -> a -> s) -> s -> [a] -> s
2020-10-21 10:44:34 <ski> `s' is the type of the accumulator state. `a' is the element type of the list
2020-10-21 10:45:00 <ski> (the version with `Foldable' is more general, in that it can also work over other ordered collections than lists)
2020-10-21 10:45:23 × sleepingisfun quits (~sleepingi@168.235.93.188) (Quit: hewwo)
2020-10-21 10:45:47 <nicknick> How can I use lambdabot to solve this? f :: Num a => (a -> a -> a) -> a -> [a] -> [a]
2020-10-21 10:46:31 <ski> no
2020-10-21 10:46:42 bliminse joins (~bliminse@host109-158-26-29.range109-158.btcentralplus.com)
2020-10-21 10:46:49 <nicknick> Sad :(
2020-10-21 10:47:00 <ski> @djinn (a -> (b,c)) -> (a -> b,a -> c)

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