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2020-11-09 09:00:50 Codaraxis joins (~Codaraxis@ip68-5-90-227.oc.oc.cox.net)
2020-11-09 09:01:06 Feuermagier joins (~Feuermagi@213.178.26.41)
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2020-11-09 09:02:30 hackage ukrainian-phonetics-basic 0.2.0.1 - A library to work with the basic Ukrainian phonetics and syllable segmentation. https://hackage.haskell.org/package/ukrainian-phonetics-basic-0.2.0.1 (OleksandrZhabenko)
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2020-11-09 09:07:31 Ariakenom joins (~Ariakenom@h-82-196-111-76.NA.cust.bahnhof.se)
2020-11-09 09:08:05 <xpika> Should there be a Monoid instance for Monad m => Kleisli m a a in the vein as Endo a in Data.Monoid?
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2020-11-09 09:10:33 otulp joins (~otulp@ti0187q162-6038.bb.online.no)
2020-11-09 09:11:28 <Taneb> xpika: http://hackage.haskell.org/package/monoid-extras-0.5.1/docs/Data-Monoid-Endomorphism.html there's this in monoid-extras
2020-11-09 09:11:39 <Taneb> Whawt you're after is "Endomorphism (Kleisli m)"
2020-11-09 09:11:50 <Taneb> (it works for any category)
2020-11-09 09:15:23 <Feuermagier> what does the :set operator do? - and where does it belong (seen it in a stackoverflow post)
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2020-11-09 09:16:35 christo joins (~chris@81.96.113.213)
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2020-11-09 09:17:40 enoq joins (~textual@194-208-146-143.lampert.tv)
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2020-11-09 09:17:48 <xpika> Taneb: Thanks
2020-11-09 09:18:50 × bitmagie quits (~Thunderbi@200116b8068e9d000cdbc28af571c7f9.dip.versatel-1u1.de) (Quit: bitmagie)
2020-11-09 09:19:02 <xpika> question: Are Monads Monoids?
2020-11-09 09:20:49 × christo quits (~chris@81.96.113.213) (Remote host closed the connection)
2020-11-09 09:21:04 <xpika> wikipedia doesn't seem to suggest it. https://en.wikipedia.org/wiki/Monad_(category_theory)
2020-11-09 09:21:24 <Taneb> xpika: the short answer is "no", but there's a long answer which has "yes" as the conclusion
2020-11-09 09:22:06 × heatsink quits (~heatsink@107-136-5-69.lightspeed.sntcca.sbcglobal.net) (Remote host closed the connection)
2020-11-09 09:22:24 <Taneb> So as monoid as is conventionally understood is a set with an associative binary operation that has an identity
2020-11-09 09:22:37 <Taneb> By this definition, a monad is not a monoid (it's not even a set)
2020-11-09 09:23:07 × adm quits (~adm@43.229.88.236) (Remote host closed the connection)
2020-11-09 09:23:08 <Taneb> But through the power of category theory, this definition can be generalized to a "monoid object on a monoidal category"
2020-11-09 09:23:45 92AABGYX7 joins (~adm@43.229.88.236)
2020-11-09 09:24:16 <Taneb> A monoidal category is a category with a bifunctor * and special object 1 such that A * (B * C) is isomorphic to (A * B) * C and A * 1 is isomorphic to A is isomorphic to 1 * A
2020-11-09 09:24:21 <maralorn> xpika: There is the sane definition of Monoid, which every mathematician knows. According to that one a Monad is not a Monoid. And then there is a category theory definition of Monoid, which I think out of 30 professors at my department max. 2 know, and as Taneb explains, that one works for Monads.
2020-11-09 09:24:53 <Taneb> We can make the category of sets a monoidal category with * being ordered pairs and 1 being a singleton set (like () )
2020-11-09 09:26:12 <Taneb> A monoid object is an object M in a monoidal category, with morphisms 1 => M and M * M => M, with certain sensible laws corresponding to associativity and identity
2020-11-09 09:26:26 × tomboy64 quits (~tomboy64@gateway/tor-sasl/tomboy64) (Remote host closed the connection)
2020-11-09 09:26:29 <Taneb> If we choose the category of sets as our monoidal category we get the traditional definition of monoids
2020-11-09 09:27:05 tomboy64 joins (~tomboy64@gateway/tor-sasl/tomboy64)
2020-11-09 09:27:44 <Taneb> Now, let's take another category, the category whose objects are functors from set to set and whose morphisms are natural transformations
2020-11-09 09:28:14 <Taneb> This can be made monoidal, taking * to be composition of functors and 1 to be the identity functor
2020-11-09 09:28:23 <Taneb> Monoids in *this* category are exactly monads
2020-11-09 09:28:29 mputz joins (~Thunderbi@dslb-084-058-211-084.084.058.pools.vodafone-ip.de)
2020-11-09 09:28:38 <Taneb> (this is where the joke "monads are just monoids in the category of endofunctors, what's the problem?" comes from)
2020-11-09 09:28:50 <Taneb> xpika: I don't know how useful this is but I hope it's at least interesting
2020-11-09 09:29:00 hackage libfuse3 0.1.2.0 - A Haskell binding for libfuse-3.x https://hackage.haskell.org/package/libfuse3-0.1.2.0 (yohashi)
2020-11-09 09:30:53 raichoo joins (~raichoo@213.240.178.58)
2020-11-09 09:31:00 Franciman joins (~francesco@host-79-36-167-172.retail.telecomitalia.it)
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2020-11-09 09:31:37 <xpika> Taneb: No, it's good. I realized the other day that since I could make a monoid out of monads that I could use the fold function for instance to fold a list of Kleisli arrows
2020-11-09 09:32:38 <Feuermagier> how can I concatenate strings with space, but only if the concatenated-with string is not empty? - (so I dont get double spaces)
2020-11-09 09:33:01 hackage r-glpk-phonetic-languages-ukrainian-durations 0.1.3.0 - Can be used to calculate the durations of the approximations of the Ukrainian phonemes. https://hackage.haskell.org/package/r-glpk-phonetic-languages-ukrainian-durations-0.1.3.0 (OleksandrZhabenko)
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2020-11-09 09:35:30 hackage phonetic-languages-properties 0.3.0.0 - A generalization of the uniqueness-periods-vector-properties package. https://hackage.haskell.org/package/phonetic-languages-properties-0.3.0.0 (OleksandrZhabenko)
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2020-11-09 09:42:32 <xpika> > (\x y -> unwords . words $ [x,y]) "hello " " world"
2020-11-09 09:42:34 <lambdabot> error:
2020-11-09 09:42:34 <lambdabot> • Couldn't match expected type ‘Char’ with actual type ‘[Char]’
2020-11-09 09:42:34 <lambdabot> • In the first argument of ‘\ x y
2020-11-09 09:42:44 invaser joins (~Thunderbi@31.148.23.125)
2020-11-09 09:42:48 <xpika> > (\x y -> unwords . words $ (x++y)) "hello " " world"
2020-11-09 09:42:50 <lambdabot> "hello world"
2020-11-09 09:43:22 cocreature joins (~cocreatur@eirene.uberspace.de)
2020-11-09 09:43:32 <xpika> > (\x y -> unwords . words $ (x++y)) "hello " " new world"
2020-11-09 09:43:34 <lambdabot> "hello new world"
2020-11-09 09:44:00 × adm_ quits (~adm@43.229.88.236) (Read error: Connection reset by peer)
2020-11-09 09:44:09 × adm quits (~adm@43.229.88.236) (Ping timeout: 260 seconds)
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2020-11-09 09:44:53 <Feuermagier> xpika, interesting! thanks!
2020-11-09 09:45:06 × invaser quits (~Thunderbi@31.148.23.125) (Read error: Connection reset by peer)
2020-11-09 09:45:38 <xpika> >"hello" ++ " "++dropWhile (==' ') " world"
2020-11-09 09:45:43 xff0x joins (~fox@2001:1a81:531b:1600:ec8f:61b3:570e:bcbc)
2020-11-09 09:46:12 britva joins (~britva@31-10-157-156.cgn.dynamic.upc.ch)
2020-11-09 09:46:38 christo joins (~chris@81.96.113.213)
2020-11-09 09:46:39 <xpika> > "hello" ++ " "++dropWhile (==' ') " world"
2020-11-09 09:46:41 adm joins (~adm@43.229.88.236)
2020-11-09 09:46:41 <Feuermagier> xpika, can I apply this to a list of Strings, so that it concatenates the entire list like "concat"?
2020-11-09 09:46:42 <lambdabot> "hello world"
2020-11-09 09:47:40 <xpika> Feuermagier: yes

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