xameer :qed: · @xameer
158 followers · 2419 posts · Server mathstodon.xyz
Tried to bootstrap a qna session on the slides i recently read and posted here , let's see where it goes
#functor #presheafs #categoryttheory #agda #coq #haskell
Will mention the credits if op of those parts are okay with it
L( my answers) to ( questions in left), feedback comments criticism are welcome
#haskell #coq #agda #categoryttheory #presheafs #functor
⎯ΘωΘ⟶ · @yog
203 followers · 852 posts · Server mathstodon.xyzRecall that a #colimit of a #diagram in a #category C, that is, of a #functor F:J→C, is #given by a #universal [[#cocone]] for F. A [[#co #cone]] for F is a #natural #transformation from F to a #constant diagram,
Δ(c)=(J→1→cC),
so that a cocone for F is an #object of a #comma category,
F↓Δ,
where Δ:C1→CJ is the #diagonal functor #obtained by #pulling #back #along the #unique functor J→1. A universal cocone is #simply an #initial object of F↓Δ.
#initial #simply #unique #along #back #pulling #obtained #diagonal #comma #object #constant #transformation #natural #cone #co #cocone #universal #given #functor #category #diagram #colimit
Julien M. · @julm
485 followers · 4935 posts · Server framapiaf.org#Haskell
« #Functor and #Bifunctor are both in #base, but what about #Trifunctor? #Quadrifunctor? There must be a better solution than creating an infinite tower of #typeclasses. Here's the #API I managed to implement »
https://gelisam.blogspot.com/2017/12/n-ary-functors.html
#TypeInType
#haskell #functor #bifunctor #base #trifunctor #quadrifunctor #typeclasses #api #typeintype