I’m going to come clean right off the bat. The title of this post is my half-hearted attempt at clickbait: what you are about to read can’t reasonably be described as a security issue. It barely even qualifies as advice, in that the thing I intend to demonstrate you should NEVER DO is something you didn’t have any plans to do in the first place.

It’s really more of a fun curiosity, and yet another entry in my series of weird things you can do with macros.

I am DELIGHTED to announce the release of version 1.0.0 of Rainbow Trails. It contains a small but meaningful number of bug fixes and filed off edge cases, and includes a completely reworked and highly configurable new timing system allowing precise control over the speed the rainbows traverse the buffer. It also features some improvements to highlighting.

If you already use Rainbow Trails, it’s a substantial improvement. If you don’t already use Rainbow Trails, now is a great time to start!

I wrote a new plugin over Easter. It is called Rainbow Trails¹ and it adds a touch of MAGIC to your motions.

If your life could do with a spot of COLOUR, You should go install it now!

The Question

After seeing the macro Game of Life, Benoit de Chezelles asked on Mastodon:

I replied:

But just because something isn’t practical, doesn’t mean it’s not possible, and so I decided to write this post to explain how you can write a macro that acts differently depending on whether anf,motion succeeds or fails.

The Challenge

Benoit politely declined to give me a real-life scenario where he needed this, so I whipped up the following CONTRIVED editing task.

I’ve never done Advent of Code before, and I wasn’t planning to do it this year¹, but for some reason I decided to try my hand at solving the 2023 event’s Day 1’s challenges in Vim, using only its editing commands. (So ex commands are allowed, but Vimscript’s more programmerly constructs — functions, loops, conditionals, etc. — aren’t.)

It was fun!

So much fun, in fact, that I ended up carrying on and completing a bunch more of the challenges.²

I have devised an entirely new method of sorting numbers. Quicker¹ than quicksort, more EFFERVESCENT than bubblesort, I present to you:

Vim Macro Sort

Vim Macro Sort uses NO Vimscript, NO chicanery with control characters, and it NEVER leaves normal mode. It’s just a plain old ASCII text file with a bunch of editing commands in it.

When I found out that Bram had died I posted a short thread on Mastodon, but I haven’t written anything here yet because I haven’t quite been able to work out why it hit me as hard as it did and what I wanted to say about it.

Two months on, I still haven’t really figured it out, so I’ll just say that, by all accounts, Bram was an exceptionally generous person, and note that in the handful of extremely limited interactions I had with him I always came away feeling positive, which hasn’t always been my experience with other open source projects.

Vim’s insert mode completion has a very nice feature where you can start typing a natural language word and then press Ctrl-XCtrl-K to complete it.

By default, it pulls the words used for the completions from the file specified with your 'dictionary' option, but this requires you to have such a file, which is not always¹ the case for the computers I do my Vimmin’ on.

But there is a backup! If 'dictionary' is empty, and you have spell checking switched on, then Vim will use the active word list(s) from its spell checking feature for completion.