Irreal

Here’s a pretty hard challenge—at least I found it challenging. Given this Lorem Ipsum

Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod
tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At
vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren,
no sea takimata sanctus est Lorem ipsum dolor sit amet.

list the unique, capitalized words in alphabetical order:

Accusam
Aliquyam
Amet
At
Clita
Consetetur
Diam
Dolor
Dolore
Dolores
Duo
Ea
Eirmod
Elitr
Eos
Erat
Est
Et
Gubergren
Invidunt
Ipsum
Justo
Kasd
Labore
Lorem
Magna
No
Nonumy
Rebum
Sadipscing
Sanctus
Sea
Sed
Sit
Stet
Takimata
Tempor
Ut
Vero
Voluptua

The winning Vim solutions use 23 keystrokes but the best I can do is 32. My solution:

Most of the work involved the two query-replace-regexp calls but I couldn’t figure out a way to do it in one without causing other problems. The call to the external sort may be a technical violation but I’m claiming that we’re grandfathered in by Tim on that.

I think the Vimers did so well because Vim has an internal sort that’s easy to invoke. I’m sure many of you can beat my pathetic 32 so leave a comment with your better solutions.

I’ve commented many times on Xah Lee’s Emacs and Emacs Lisp tutorials. I’ve learned a lot from them and the Elisp tutorials helped me transfer my Common Lisp and Scheme knowledge to Emacs.

The tutorials are on the Web and available for free at the links above but Lee also makes them available as ad-free zip files for those who’d like a local copy. Lee charges $5 for the files but makes updates available for free. Lee has just released another archive of the tutorials so this is a good time to get a copy if you’re interested. Buying the tutorials is a good way to support Lee’s effort so if, like me, you find them useful contribute the $5 if you can.

Vivkek Haldar appears to be the go to guy for Emacs quotes. Magnar Sveen’s excellent What the Emacs.d!? begins and end with a Haldar quote. Now Haldar brings us a quote from Kieran Healy on the enduring excellence of Emacs. Take a look. If you’re an Emacasien¹, it will resonate.

I’ve mentioned before that Emacs configuration is a black hole that can easily swallow any spare cycles that wander into its event horizon. Part of that for me is reading how other people do it. Over at MetaSandwich, Selah has an interesting take on how to do it correctly. One of the things that makes it interesting for me is that he is one of the few people I’ve read who do essentially what I do.

He writes about what he considers the two main problems in Emacs configuration:

1. How you should arrange the configuration file to make Emacs startup as fast as possible.
2. Where should you put things.

Selah says he used to spend a lot of time worrying about how to minimize his startup time. Then one day he realized that, hey, it doesn’t really matter. It doesn’t matter because he, like most of us, doesn’t restart Emacs very often. He starts his once or twice a week; I keep mine going for weeks at a time. I usually start Emacs only at boot time and I reboot only for an OS upgrade or, in the case of my laptop, if I’m traveling. So startup time doesn’t matter very much. As Selah points out, even if it took 30 seconds that’s less than a minute a week (for him) and maybe 5 seconds for me.

As it turns out, emacs-init-time tells me that my current startup time on my iMac is 4.8 seconds without me spending a single second trying to optimize it. Why should I worry about it? I feel confident that that’s true for most of us.

The second problem is a little more controversial. Most of the Emacs hackers that I respect tend to have a complicated configuration architecture with several files and even subdirectories. Look at Steve Purcell’s or Magnar Sveen’s configurations for examples of that strategy. I on the other hand keep pretty much everything in init.el. Recently, I boldly struck out for uncharted territory and moved machine and platform specific configurations into their own small files that get loaded automatically based on the system-name and system-type variables but mostly everything lives in a single file.

I’ve often felt like the Maytag repairman because of my preference for a single file but now Selah joins the party and makes a pretty good case for having a single file. He even gives a little code that arranges a handy index of your init.el for use with imenu. That’s nice but I don’t need even that. I pretty much know where things are in my init.el and I have headers for the various sections so I can go right to them with incremental search.

In the end, of course, there’s no right or wrong way, just personal preferences. Still, I seem to be endlessly fascinated by how people do their configurations (and what’s in them, of course) so if you want to share your methods, leave a comment.

Most Irreal readers have probably already seen Mickey’s post on Evaluating Lisp Forms in Regular Expressions, but he mentions one trick that is too good to miss so I’m going to repeat it.

Not too long ago I was trying to find a way to swap several occurrences of two words in a buffer (I think it was for the VimGolf lamb had a little Mary challenge). I did find a way but I wasn’t very happy with it. In his post, Mickey shows a way that is, in retrospect, obvious but which didn’t occur to me. Suppose you have

Jill and Jack went up the hill to fetch a pail of water.
Jill fell down and broke his crown and Jack came tumbling after.

and you want to switch Jill and Jack so that you have the traditional rhyme. Here’s Mickey’s trick: do a replace-regexp (or query-replace-regexp) with a FROM string of

\(Jill\)\|Jack

and a TO string of

\,(if \1 "Jack" "Jill")

Notice that we capture only one subgroup and use it to determine which replacement word to use. If \1 is nil then we didn’t match Jill so we must have matched Jack and we want to use Jill as the replacement. On the other hand, if \1 is not nil then we matched Jill and want to replace it with Jack. Very nice.

Mickey’s got some other nice tricks you can do with the form-based TO string in replace-regexp so be sure to read his post if you haven’t already.

Here’s an interesting VimGolf challenge that nicely demonstrates the power of CUA selection mode. Given the word frequency chart

     align here
the        56271872
of        33950064
and        29944184
to        25956096
in        17420636
I        11764797
that        11073318
was        10078245
his        8799755
he        8397205
it        8058110

align the frequency counts so that it looks like

     align here
the  56271872
of   33950064
and  29944184
to   25956096
in   17420636
I    11764797
that 11073318
was  10078245
his  8799755
he   8397205
it   8058110

My first thought was to use align-regexp but that command doesn’t have a shortcut key sequence and the best regular expression I could find was [1-9]. A pretty nice solution but it certainly won’t win on keystrokes.

After messing around a bit, I came up with a solution of 4 keystrokes using the CUA rectangle functionality.

Notice that the trailing digits of a few of the frequency counts aren’t in the rectangle but they get dragged along anyway. I’ve only been using CUA rectangle mode for a short while but I am continually amazed at how powerful it is. Certainly this problem doesn’t look like a rectangle problem but CUA rectangle mode solves it very handily anyway.

Sadly, those darn Vim people were able to solve this in 3 keystrokes so if you can shave off a stroke or two be sure to leave a comment. I don’t think you can squeeze any more keystrokes out of the rectangle strategy so you’ll probably need something entirely different.