Irreal

Nicolas Martyanoff has a post on something I didn’t know about: Emacs Tempo templates. I’ve been an Emacs user for somewhere between 15 and 20 years and I’d never heard of Tempp templates. On the one hand that’s pretty surprising. On the other hand, we all know that learning Emacs is a lifelong journey that is never completed.

As most of you know, I’m a Yasnippet user and find it very useful even for non-programming chores so I’m not in the market for another templating engine but if you’re new to templating, Tempo may be worth a look. I don’t have any experience with it, obviously, but based on Martyanoff’s description I’d judge that Yasnippet is easier to use and learn and seems more flexible too.

Martyanoff says that one of the virtues of Tempo is that it’s simple but I find it harder to use than Yasnippet so my advice to the template n00b is to use Yasnippet. Still, as always, Emacs let you have your way. Along with skeletons there are three¹ template systems you can use with Emacs so there are plenty of choices.

Here’s some good news: The F-Droid site now has a more or less complete implementation of GNU Emacs for the Android platform. I’m not sure Emacs on a phone is all that useful other than for dealing with Org files and there are several apps already available for that on both the Android and iOS platforms. On a tablet, though, it could be a real game changer. Emacs on a tablet—perhaps with a real keyboard—would enable truly remote work. Yes, you can carry your laptop around as many of us do but a tablet is much easier especially in situations such as air travel.

We here at Irreal are famously iPhone/iPad users so F-Droid’s announcement doesn’t affect us directly but perhaps it will encourage Apple to relax their no interpreters rule on the platform. I understand their reasoning but having a workable Emacs on the iPad would be such a win that it would be worth it, especially with appropriate sandboxing.

If we had Emacs on the iPad it would change my mobile computing strategy completely. I’d get a good keyboard for the iPad and probably almost always leave my laptop at home. The iPad, modulo software, is already as powerful as many laptops and could easily support remote work. I have a family member—in banking not software—who already uses his iPad as his exclusive mobile device. There’s no reason we developers couldn’t do the same. All we need is Emacs. I love my laptop and don’t foresee myself ever giving it up but it sure would be nice to have an easy-to-carry device for remote work.

I’ve long been an enthusiastic Yasnippet user and have written about it a few times. Its canonical use case is in programming to fill in primitives such as the for loop in C or a class definition in Python but I rarely use it that way. I mostly use it with Org files to do things like create the header for blog posts, add boilerplate, do simple expansions like latex → LaTeX, insert daily checklists into my journal, and add code blocks to my blog posts.

These are all pretty simple operations that don’t begin to use all that Yasnippet has to offer. Jack of Some has an excellent video on how to superchage Emacs with Yasnippet. He does, of course, cover simple text substitutions but he also shows how to use its more advanced features.

One particularly nice example is his expansion of a Python class definition. As he adds arguments to the definition, the snippet automatically adds the code to initialize the instance with the arguments’ values. More generally, he shows how you can embed Elisp into the snippet template to do non-trivial things like insert the name of the current file into the text.

One thing I didn’t know how to do was to add “global snippets”. Usually snippets are only active for a particular type of file but it’s possible to have snippets that are always available. Take a look at the video to see how to do this.

The video is two years old but I just came across it. It’s definitely worth a few minutes of your time. It’s a few seconds over 12 minutes long so it should be easy to fit into your schedule.

Sooner or later almost every Emacs user discovers Dired and becomes a dedicated—or even fanatical—user. It’s basically a file manager but embedded within Emacs. As I’ve mentioned before, I tend to be an old-timey sort of guy so my natural inclination is to do my file manipulations on the command line just as I have for years but even I am a Dired convert and do essentially all my file work with it.

Nicolas Martyanoff is pretty much the same but he has a problem with the default listing. His complaint is that there’s a lot of unnecessary information, often formatted in an inconvenient way. That would be a minor annoyance except that it often causes the (arguably) most important datum, the file name, to wrap and be difficult to read.

Fortunately, Dired is reasonably configurable by setting various variables. Martyanoff took advantage of this to produce a nicer Dired listing. The dates are all in ISO format and file sizes are given in bytes rather than the generally useless number of file blocks. The resulting listing is more pleasant and easier to read as you can see from Martyanoff’s post.

Dired, of course, gets its information from ls so getting a better date and size format just means changing the arguments to ls, which are specified in one of the above mentioned variables. Sadly, the required changes are specific to the GNU version of ls so you’ll have to use it.

Martyanoff doesn’t mention if this effects Wdired but there’s no reason it should. That would be a showstopper for many of us. Other than that, this seems like a nice change that might be worth implementing. There is just a bit of Elisp involved so it’s easy to try it out and experiment with it.