Clojure Deref (Apr 19, 2024)

19 April 2024
Alex Miller

Welcome to the Clojure Deref! This is a weekly link/news roundup for the Clojure ecosystem (feed: RSS). Thanks to Anton Fonarev for link aggregation.

From the core

We have three big chunks of work remaining for 1.12. The first one, reworking the symbolic array type representation is complete and captured in CLJ-2807. That will roll back the previous implementation added in alpha6 and replace it with a new representation. Array symbols will have the syntax ComponentType/dimension, eg String/1 or long/2. More to say on that when we release.

The second piece is reworking the method value, qualified methods, and param-tags implementation. The big picture is that qualified methods withparam-tags must resolve to a single method (no change there), and that qualified methods without param-tags will otherwise support fully reflective invocation (as method values, in all arities).

Additionally, we’re going to alter the syntax of qualified instance methods (Classname/.method) to make them distinct from static methods (Classname/method, as always), and constructors will continue to be Classname/new. There are existing cases in the JDK (Double.isNaN() for example) that have both static and instance methods that overlap in effective arity (instance methods take the instance object as first "arg"). Method values without param-tags have no way to differentiate between these and that was causing a lot of pain in the implementation. This work is nearing completion.

The final piece is functional interface conversion. While the hard parts are mostly done, there are some gnarly bits in optimizing method values passed as FIs (avoiding intermediate thunks or converters) but also getting close on this. At an interim point this week I ran some wide regression testing against community projects and found a few interesting cases, some were actual latent bugs, some drove some refinments. This is critical work in making this a clean release that does not break existing code, but it takes time.

Have been working on Clojure/Conj stuff too, hoping to get info about CFP, tickets, and sponsorship out in the next month.

Blogs, articles, and projects

Libraries and Tools

New releases and tools this week: