Irreal

Recently, someone posted a link to Artur Malabarba’s old blog. Sadly, Malabarba no longer posts to it but it still has a lot of good and relevant information. The link was to a Malabarba post about directory local variables.

The idea is that you can place various variables controlling Emacs in a file in a directory and those variables will apply only to other files in that directory (and its subdirectories). It’s ideal, for example, if you have a project directory and would like to apply some Emacs customizations to the project’s files. You can specify that variables should apply only to file having a specific major mode or to all files.

The file format is a tiny bit fussy but fortunately you can simply call add-dir-local-variable and it will prompt you for the necessary information and write it to the local variables file, creating it if necessary.

I really like the idea but it never seems to work for me. That’s mainly because almost all the customizations I want to make involve running some code—invoking a minor mode, for example. File local variables support this (see Malabarba’s post or the documentation for the details) but every time I try to use it I get error messages about exceeding maximum evaluation depth. I wrote about this back in October.

Malabarba’s post is short and well worth a read if you’re not familiar with directory local variables or have mostly forgotten the details.

James Dyer has another useful Emacs discovery. His workflow often involves copying large files, which he does from Emacs using Dired. Even though he’s configured Emacs to use rsync for Dired copies, the transfer can still take some time and Emacs hangs while the copy is in progress..

It turns out that as of Emacs 29 there is a nice solution. You can set dired-async-mode to on and all the Dired operations will happen asynchronously. That includes things like renaming, which, of course, takes no time at all but it really matters mostly for copying.

There isn’t much to say about the post. It boils down to “if you do a lot of copying with Dired, then switch on dired-async-mode.” Check out Dyer’s post for the full story but, as I say, it’s a short story. Nevertheless, it’s a useful tip and well worth knowing about

Emacs Elements has a new video that takes a quick look at Bookmark+. It serves the same purpose as the builtin bookmark application but is extended in many ways. I’ve been using it for many years ever since abo abo wrote about it and his hack to make jumping to bookmarks easy (I wrote about it here).

The video details some of the additional types of bookmarks that bookmark+ supports. You can, for example, set a bookmark to a URL and bookmark+ will open it in the browser for you. I use that all the time to quickly jump to the Irreal site when I’m working on a post.

Another nice capability is to open a specialized buffer. For example, I have a bookmark to Ibuffer that will open a buffer with the current buffer list. Similarly, you can set a bookmark to a directory. That can be convenient when you have a directory with a long path. For instance, I have a bookmark to the the elpa directory that lives in the (for me) hard to type .emacs.d directory. When you open such a bookmark you get a Dired buffer for the target directory.

The video demonstrates another bookmark type that I don’t use but could be handy: you can mark a region in a file and bookmark that. When you open the bookmark, you jump right to it and it’s highlighted. Similarly, you can bookmark any position in a file although this may be possible with native bookmarks too.

The video is definitely worth a look. It’s 8 minutes, 13 seconds so it should be reasonably easy to find time for it.

Fedora Magazine has an interesting article in which a journalist, odisej, discovers using Emacs as his writing tool. His article is a sort of perfect case study because odisej has no real technical background so his take on using Emacs for writing is that of someone without expertise in text editors. Of course, he does have experience with “word processors” and has tried a lot of them. He even tried using ancient ones such as WordStar and Word Perfect but none of them clicked for him. Then he tried Emacs and finally discovered his ideal writing environment.

Of course, Emacs is famously idiosyncratic, having existed long before IBM decided what the one true user interface should look like. This means that Emacs is infamous for its steep learning curve and odisej certainly suffered from it but once he learned the basics he knew he had found the perfect writing tool.

What makes it so perfect? He doesn’t say so explicitly but as usual it’s Emacs’ configuration and extensibility that makes the difference. For example, odisej likes wider margins than the default and Emacs makes it easy to set them to his preferred value. Of course, most editors can do that but Emacs makes just about everything configurable.

Then there’s extensibility. Emacs has thousands of packages available that can provide practically any capability the user desires. Odisej added flyspell and wc-mode to his configuration to take care of spelling correction and word counting. Again, most editors provide some flavor of these functions but Emacs has several packages to do them that differ slightly in how they work and how they present their results to the user. As always, Emacs lets you have it your way.

If you want to view Emacs from a writer’s point of view, take a look at odisej’s post.

Someone posted a link to an old Bozhidar Batsov post that discusses a nifty little function that automates a simple but annoying manual process. Those of you who use package.el or the use-package macro are probably familiar with the problem. You update a package but it doesn’t load or work correctly. Usually, this is the result of byte compilation problems.

The answer is to uninstall the package and then install it again. It’s not hard but it is a pain. Batsov’s solution is to simply capture the process in a small function. The whole thing amounts to:

1. Unloading the package
2. Reinstalling the package
3. Requiring the package

To make things really easy, he also has an interactive version that does a completing read to specify the package to reinstall. The completing read is populated with the complete package list so it’s easy to get the name right.

If you handle your packages with package.el you should definitely take a look at Batsov’s post. It’s short and easy to read and it’s also easy to just copy his code and insert it right into your init.el.