Reasonably Polymorphic

Last time, we took a stroll down memory lane to review some ancient code I wrote, and see what/how I’d do things differently now.

I’ve been wanting to get back into the habit of blogging, and thought a fun project would be to go back through my old code and review it as the programmer I am now.

In my last post, I was struggling towards an algebraic theory of music.

For the last few months, I’ve been trying to come up with a nice, denotational basis for what music is.

I’ve had a little time off of work as of late, and been spending it in characteristically unwise ways.

A reader recently got in touch with me regarding my 2017 blog post Review: Theorems for Free.

The other day, someone asked: Why doesn’t [the Data.Map function] unionWith :: (a -> a -> a) -> Map k a -> Map k a -> Map k a allow for different value types the way intersectionWith :: (a -> b -> c) -> Map k a -> Map k b -> Map k c does?

Usually I write about solutions to problems I’ve worked out, but I’ve found myself increasingly becoming interesting in where solutions come from.

Just a quick one today, but I wanted to point out a little trick you can do with Haskell’s typeclass inference.

There’s a common anti-pattern I see in beginner-to-intermediate Haskell programmers that I wanted to discuss today.