Today, 2025-05-07, at 1830 UTC (11:30 am PDT, 2:30 pm EDT, 7:30 pm GMT, 20:30 CET, …) we are streaming the 43th episode of the Haskell Unfolder live on YouTube.
The Haskell Unfolder Episode 43: monomorphism restriction and defaulting
In this episode, we are going to look at two interacting “features” of the Haskell language (the monomorphism restriction and defaulting) that can be somewhat surprising, in particular to newcomers: there are situations where Haskell’s type inference algorithm deliberately refuses to infer the most general type. We are going to look at a number of examples, explain what exactly is going on, and why.
About the Haskell Unfolder
The Haskell Unfolder is a YouTube series about all things Haskell hosted by Edsko de Vries and Andres Löh, with episodes appearing approximately every two weeks. All episodes are live-streamed, and we try to respond to audience questions. All episodes are also available as recordings afterwards.
We have a GitHub repository with code samples from the episodes.
And we have a public Google calendar (also available as ICal) listing the planned schedule.
There’s now also a web shop where you can buy t-shirts and mugs (and potentially in the future other items) with the Haskell Unfolder logo.