tag:blogger.com,1999:blog-1777990983847811806.post1541038340050163639..comments2021-11-30T03:48:57.515-08:00Comments on Haskell for all: From mathematics to map-reduceGabriella Gonzalezhttp://www.blogger.com/profile/01917800488530923694noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-1777990983847811806.post-77888068501978539072016-03-05T19:24:44.239-08:002016-03-05T19:24:44.239-08:00You're right. I fixed it so that `fw` doesn&#...You're right. I fixed it so that `fw` doesn't pull out the `Monoid` constraint all the way to the top levelGabriella Gonzalezhttps://www.blogger.com/profile/01917800488530923694noreply@blogger.comtag:blogger.com,1999:blog-1777990983847811806.post-35385180793152413892016-02-20T02:05:57.091-08:002016-02-20T02:05:57.091-08:00Hey Gabriel,
Thanks a lot for the great writeup! ...Hey Gabriel,<br /><br />Thanks a lot for the great writeup! I've got the gist of it, but am a little confused by how you can go from<br /><br />fw :: ([a] -> (Monoid m => m)) -> (a -> m)<br />bw :: (a -> m) -> ([a] -> (Monoid m => m))<br /><br />to the "idiomatic" form<br /><br />fw :: Monoid m => ([a] -> m) -> ( a -> m)<br />bw :: Monoid m => ( a -> m) -> ([a] -> m)<br /><br />where suddenly the monadic constraint is imposed on the entire type definition, rather than just the type m on one of the sides. Does this somehow conflict with the free/forgetful functor relation?evitaerchttps://www.blogger.com/profile/05839645748888899226noreply@blogger.comtag:blogger.com,1999:blog-1777990983847811806.post-82377713131518507802016-02-08T08:59:04.754-08:002016-02-08T08:59:04.754-08:00What I meant was that the more general definition ...What I meant was that the more general definition is not necessarily restricted to the category HaskGabriella Gonzalezhttps://www.blogger.com/profile/01917800488530923694noreply@blogger.comtag:blogger.com,1999:blog-1777990983847811806.post-5492313337960079402016-02-08T08:32:11.862-08:002016-02-08T08:32:11.862-08:00I'm confused by how the category theoretic def...I'm confused by how the category theoretic definition of isomorphism is supposed to be broader than the one you've given. Here it is from Wikipedia: " A morphism f : X → Y in a category is an isomorphism if it admits a two-sided inverse, meaning that there is another morphism g : Y → X in that category such that gf = 1X and fg = 1Y, where 1X and 1Y are the identity morphisms of X and Y, respectively." Which is exactly what you said, but in the category Hask.Adam Strandberghttps://www.blogger.com/profile/07738005919870453367noreply@blogger.comtag:blogger.com,1999:blog-1777990983847811806.post-2230131022912894072016-02-04T00:57:51.657-08:002016-02-04T00:57:51.657-08:00Great explanations of what a left-adjoint and a fo...Great explanations of what a left-adjoint and a forgetful functor are. Now I can understand more of Edward Kmett's writing.Anonymoushttps://www.blogger.com/profile/14579555431187914415noreply@blogger.com