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<oerjan> le/rn soviet union/In ancient history, the Soviet Union used to be the THEM. They believed in absurd principles like "Better Red than Dead". Then Ronald Reagan invented Star Wars to destroy it, after which there seemed to be no the THEM for a while.
author | HackBot |
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date | Tue, 16 Feb 2016 21:39:22 +0000 |
parents | 8f79561a34c2 |
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2013-01-27.txt:09:43:46: <shachaf> monqy: imo the Await part is like (r,CoYoneda k r) 2013-01-27.txt:09:44:24: <shachaf> monqy: btw are you a CoYoneda expert 2013-01-27.txt:09:45:12: <shachaf> monqy: well you know how CoYoneda IORef = a read-only IORef 2013-01-27.txt:09:47:24: <shachaf> CoYoneda f a = forall r. CoYoneda (r -> a) (f r) 2013-01-27.txt:09:49:50: <shachaf> monqy: anyway when f is a functor CoYoneda f is isomorphic to f?? 2013-01-27.txt:09:50:51: <shachaf> maybe THIS CoYoneda will be more to your liking!!!!!!!!!! http://ncatlab.org/nlab/show/co-Yoneda+lemma 2013-01-28.txt:05:37:44: <shachaf> kmc: By the way, you know ho CoYoneda IORef gives you a "read-only IORef" that can't do any other effects? 2013-02-07.txt:08:55:26: <shachaf> monqy: should i prefer yoneda or coyoneda 2013-02-07.txt:09:06:02: <monqy> shachaf: idk i havent studied them much at all?? my only real "experience" with them is that one time you asked me about how yoneda looks like partially applied >>= and coyoneda like =>>, or something like that 2013-02-07.txt:09:09:06: <shachaf> but coyoneda seems "more obvious to me" 2013-02-07.txt:09:09:33: <shachaf> also coyoneda can be meaningful for things that arne't functors 2013-02-07.txt:09:13:21: <shachaf> ion: do you know what coyoneda is 2013-02-07.txt:09:16:06: <shachaf> "CoYoneda Tree" keeps a tree, and a function to be mapped over it. 2013-02-07.txt:09:17:52: <shachaf> So CoYoneda Tree a = (Tree x, x -> a), for some x. 2013-04-02.txt:23:20:43: <shachaf> CoYoneda is easy. 2013-04-02.txt:23:21:41: <shachaf> CoYoneda is related to Functor. 2013-04-02.txt:23:35:10: <shachaf> Bike: As you probably guessed, Foo is CoYoneda. 2013-04-02.txt:23:37:57: <shachaf> You can treat (CoYoneda IORef) as a read-only IORef, sort of. 2013-04-02.txt:23:38:23: <shachaf> Bike: However: When f is a Functor, CoYoneda f is isomorphic to f 2013-04-02.txt:23:40:54: <shachaf> Bike: btw Yoneda is like CoYoneda except backwards 2013-04-02.txt:23:41:17: <shachaf> I think CoYoneda is more intuitive than Yoneda 2013-04-02.txt:23:57:19: <shachaf> oerjan: What do you think: Yoneda or CoYoneda? 2013-04-02.txt:23:59:13: <shachaf> oerjan: data CoYoneda f a = forall x. CoYoneda (f x) (x -> a) 2013-04-02.txt:23:59:38: <shachaf> when f is a functor it's isomorphic to Yoneda f and to CoYoneda f 2013-04-03.txt:00:00:01: <shachaf> btw Bike did you write lift and lower for CoYoneda 2013-04-03.txt:00:07:28: <shachaf> Where CoYoneda has the *arguments* to fmap, Yoneda has the *result* of fmap. 2013-04-03.txt:00:09:51: <shachaf> I guess you could say: fmap :: CoYoneda f a -> f a 2013-04-03.txt:09:08:43: <shachaf> ais523: Do you prefer one of Yoneda/CoYoneda? 2013-04-03.txt:09:09:23: <shachaf> data CoYoneda f a = forall x. CoYoneda (f x) (x -> a)