Sheaves in Haskell (opens in new tab)

I recently found a way to represent sheaves in Haskell. It was a fun couple of weeks of head-scratching. But as much as I wanted it to, the code in my doesn’t speak for itself. So I’m writing this blog post to share my newfound understanding. In this post I’ll be assuming a pretty solid knowledge of category theory (but not of sheaves, which I’ll be explaining). If you aren’t, wait until my next post which will give a more practical introduction to sheaves. I don’t think it’s necessary to use...