Here’s another tidy bit of Clojure that makes me happy…
Of course it’s easy to sort items in the natural order:
(sort [1 3 4 2]) ; => (1 2 3 4)
Or via a mapping to elements that sort in a natural order:
(sort-by count ["xx" "xxx" "x"]) ; => ("x" "xx" "xxx")
But how do we sort in a user-defined, fixed order?
I finally got around to re-recording and posting this talk on Clojure’s transducers that I gave last year to the Austin Clojure Meetup:
The gentleman behind Clojure Diary was kind enough to recently post a video based on a small comment I made on his YouTube channel: Clojure Diary - Elegant way of filtering maps based on key value pairs.
(Please check out his channel as he’s doing a great job regularly posting videos about his journey through Clojure!)
In my comment I used a little submap? function from my personal
utilities library that I’ve gotten a lot of mileage out of the last
year or two.
I thought I’d mention it here. It’s isn’t anything magical, but I think it’s part of my personal standard library from here on out:
In the spirit of Chinese New Year, I hacked up a small extension for Emacs to render the current time of day using emoji and Chinese characters:
Various configurations for your mode line.
Wherein I argue that Clojurians should be a touch more embracing of
Java interop and that java.time is actually good.
(This post is regarding a very particular issue at the intersection of Emacs, Clojure, and CIDER, so most readers can probably skip it, but I figured the solution deserved to be somewhere on the internet.)
CIDER has this awesome feature via clj-refactor where it can
automatically add missing libspecs to your ns form as soon as you
type an aliased var name using an :as alias you have previously used
for that namespace:
Screen recording showing how CIDER and clj-refactor can add missing libspecs.
You can define a preferred set of (:as) aliases via
cljr-magic-require-namespaces in your Emacs config, and, whether
you’ve done that or not, CIDER tries hard to be smart, offering you
choices if you’ve previously used the same alias for different
namespaces in different places in your project (e.g. s/ for
clojure.spec some places and the same for clojure.string in other
places).
Moreover, CIDER evaluates the namespace form, bringing in the new requires, allowing you to just keep typing and coding, without breaking your flow.
This is all fantastic, but I ran across one particular scenario where
this kept biting me: my user namespace.
From the department of How Did I Never Learn This in 12+ Years of Clojure? comes today’s tip:
Did you know you can generate a thread dump (+ memory usage information) from a Clojure REPL with a single keystroke? I sure didn’t.
After the news from the Clojure/conj that Datomic is now free, I was excited to get home and upgrade and access newer features and high-availability. Herein are notes from how that upgrade process went that I hope will be helpful to anyone else upgrading, including difficulties I had running the official Datomic AMIs.
The Taiwan Beats Showcase is probably my favorite music event at SXSW, and I make a point to catch it every year.
This year I put together a playlist of songs by all of the performing artists for my friends at the Austin chapter of Taiwanese American Professionals.
Photo of Elephant Gym performing at SXSW 2019
I don’t know why I’m quite so tickled by this, but today I learned
that you can make multi-line git commit messages by passing multiple
-m arguments: