Emacs Lisp: Font Lock for Clojure’s Partial

I love using partial, but I dislike the length of the function name. There’s a simple solution, define another function with a shorter name that simply calls (or is) partial. This is exactly what I did in the jry library.

I liked the use of % due to partial feeling similar to creating a function using #(), and % having a special meaning inside #(). I thought they tied well together. Unfortunately, there’s an obvious problem, things would be very broken if you tried to use the ‘%’ function in an anonymous function defined with #(). Somewhere along the way this issue caused me to stop using jry/%.

Using partial is great: it’s part of the standard lib, and I don’t need to explain it to anyone who joins my team or any future maintainers of the code I write. Still, I want something shorter, and I’ve always had a background thread looking for another shorter-than-partial solution. While recently contributing to emacs-live I found the solution I was looking for: clojure-mode font lock.

The following code can now be found in my emacs configuration.

This solution feels like the best of both worlds. My code still uses the function from the standard library, my colleagues still see a function they already know, and ‘partial’ only takes up one character space in my buffer. The image below is what you’ll see if you put the above emacs-lisp in your config.

Source: Jay Fields

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