I mentioned in What’s Changed Since Scala 3.0.0 that Scala 3.1 introduced an experimental feature for safer exceptions. Let’s explore it in more detail. Java’s checked exceptions were an attempt to express in method signatures the possibility that an exception might be thrown. While laudable in theory, in practice the…

I’m giving a talk at Scale by the Bay, October 28th, on Lessons Learned from 15 Years of Scala in the Wild. Programming Scala, Third Edition is now available. …

The Scala team continues to refine Scala 3, fixing bugs, refining existing features, and introducing some experimental features for Scala 3.1. Here are a few highlights. Programming Scala, Third Edition is now available. It provides a comprehensive introduction to Scala 3 for experienced Scala developers, as well as a complete…

During my recent trip to the Ruby Mountains in Nevada, I tried out the inexpensive and compact Move Shoot Move star tracker. This isn’t a full review, just my initial impressions, as I didn’t have a lot of time to try it out (for reasons I’ll mention below). What Is a Star Tracker? Here is…

I spent a week in the Ruby Mountains of Nevada last month. I’ve posted my best pictures to Flickr. I just purchased the Syrp Genie Micro and several of their motion control devices. You can see the Micro below mounted in my camera’s hot shoe. The compatibility list says the…

Update May 22, 2022: Michel Charpentier correctly pointed out that the arguments don’t need to be by-name if they are inlined. This makes perfect sense if you think about it (which I didn’t 🤓), because we are no longer calling the invariant and fail functions; they are now gone, replaced…

Update April 3, 2022: I added the code examples below to the book’s code repo and did more extensive testing. See here for details. Update May 22, 2022: Michel Charpentier correctly pointed out that the arguments don’t need to be by-name if they are inlined. This makes perfect sense if…

Late in the Scala 3 development process, a new type scala.Matchable was introduced to fix a loophole in pattern matching. This post discusses that loophole, how Matchable fixes it, and implications of this change. For an even more concise summary of most of the notable changes in Scala 3, see…