There are plenty of high quality libraries that add missing functions from clojure.core. Just take a look at the clojure toolbox under “Misc. Functions” or “String Manipulation”. Which ones are you using?

I tried many of them, but mostly don’t use them in my projects. Instead, I usually write my own clojure.core extensions. Here are some of the benefits as I see them:

  • IMO it’s better 1 to be thinking “what patterns do I see in the project” than “what can this library do for me”.
  • If you have your own clojure.core extensions, you’ve likely given it some thought how you’ll structure them. If you didn’t then it might be the case that you have a bunch of files with less than ideal names. You’ve probably seen them already. They are sometimes called a_utils.clj, b_utils.clj, util.clj, common.clj, extra.clj, helper.clj.
  • “Where is that function defined?” Given clojure.core, 3 different libraries and your own util namespaces, where is it? This becomes somewhat easier if you’ve written your own extensions. If it’s not in clojure.core then it’s in a dedicated namespace you wrote.
  • They are not hard to maintain because in my experience they don’t change at all.
  • You won’t need to write a lot of new function. clojure.core is pretty impressive and is getting even better.
  • They are fun to write and each one is a learning opportunity.

With that out of the way, I’d like to share the namespaces and functions that I have so far. Feel free to use them and adapt to your situation. For tests see

  1. That holds up to a point of course. clojure.core extensions are usually quite simple. Security related algorithms are another matter. ↩︎