Good news, everyone! clojure-mode 5.22 is out with many small improvements and bug fixes!

While Tree-sitter is the future of Emacs major modes, the present remains a bit more murky – not everyone is running a modern Emacs or an Emacs built with Tree-sitter support, and many people have asked that “classic” major modes continue to be improved and supported alongside the newer TS-powered modes (in our case – clojure-ts-mode). Your voices have been heard! On Bulgaria’s biggest national holiday (Liberation Day), you can feel liberated from any worries about the future of clojure-mode, as it keeps getting the love and attention that it deserves! Looking at the changelog – 5.22 is one of the biggest releases in the last few years and I hope you’ll enjoy it!1

Now let me walk you through some of the highlights.

edn-mode Gets Some Love

edn-mode has always been the quiet sibling of clojure-mode – a mode for editing EDN files that was more of an afterthought than a first-class citizen. That changed with 5.21 and the trend continues in 5.22. The mode now has its own dedicated keymap with data-appropriate bindings, meaning it no longer inherits code refactoring commands that make no sense outside of Clojure source files. Indentation has also been corrected – paren lists in EDN are now treated as data (which they are), not as function calls.

Small things, sure, but they add up to a noticeably better experience when you’re editing config files, test fixtures, or any other EDN data.

Font-locking Updated for Clojure 1.12

Font-locking has been updated to reflect Clojure 1.12’s additions – new built-in dynamic variables and core functions are now properly highlighted. The optional clojure-mode-extra-font-locking package covers everything from 1.10 through 1.12, including bundled namespaces and clojure.repl forms.2 Some obsolete entries (like specify and specify!) have been cleaned up as well.

On a related note, protocol method docstrings now correctly receive font-lock-doc-face styling, and letfn binding function names get proper font-lock-function-name-face treatment. These are the kind of small inconsistencies that you barely notice until they’re fixed, and then you wonder how you ever lived without them.

Discard Form Styling

A new clojure-discard-face has been added for #_ reader discard forms. By default it inherits from the comment face, so discarded forms visually fade into the background – exactly what you’d expect from code that won’t be read. Of course, you can customize the face to your liking.

Notable Bug Fixes

A few fixes that deserve a special mention:

  • clojure-sort-ns no longer corrupts non-sortable forms – previously, sorting a namespace that contained :gen-class could mangle it. That’s fixed now.
  • clojure-thread-last-all and line comments – the threading refactoring command was absorbing closing parentheses into line comments. Not anymore.
  • clojure-update-ns works again – this one had been quietly broken and is now restored to full functionality.
  • clojure-add-arity preserves arglist metadata – when converting from single-arity to multi-arity, metadata on the argument vector is no longer lost.

The Road Ahead

So, what’s actually next for clojure-mode? The short answer is: more of the same. clojure-mode will continue to receive updates, bug fixes, and improvements for the foreseeable future. There is no rush for anyone to switch to clojure-ts-mode, and no plans to deprecate the classic mode anytime soon.

That said, if you’re curious about clojure-ts-mode, its main advantage right now is performance. Tree-sitter-based font-locking and indentation are significantly faster than the regex-based approach in clojure-mode. If you’re working with very large Clojure files and noticing sluggishness, it’s worth giving clojure-ts-mode a try. My guess is that most people won’t notice a meaningful difference in everyday editing, but your mileage may vary.

The two modes will coexist for as long as it makes sense. Use whichever one works best for you – they’re both maintained by the same team (yours truly and co) and they both have a bright future ahead of them. At least I hope so!

As usual - big thanks to everyone supporting my Clojure OSS work, especially the members of Clojurists Together! You rock!

That’s all I have for you today. Keep hacking!

  1. I also hope I didn’t break anything. :-) ↩

  2. I wonder if anyone’s using this package, though. For me CIDER’s font-locking made it irrelevant a long time ago. ↩