A Comonad of Graph Decompositions

I want to talk about a comonad that came up at work the other day. Actually, two of them, as the data structure in question is a comonad in at least two ways, and the issue that came up is related to the difference between those two comonads.

This post is sort of a continuation of the Comonad Tutorial, and we can call this “part 3”. I’m going to assume the reader has a basic familiarity with comonads.

Inductive Graphs

At work, we develop and use a Scala library called Quiver for working with...