Tag Archives: Emacs

Emacs display-battery-mode

Posted on 2012-06-09 by jcs

I have occasionally run across the Emacs display-battery-mode command—it’s in Aaron Hawley’s excellent reference sheet, for example. I never bothered really looking at it because my MacBook Pro already has an battery status icon on the menu bar. Today, out … Continue reading →

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The Emacs comment-dwim Command

Posted on 2012-06-05 by jcs

I really like the Emacs comment-dwim command. The dwim—do what I mean—neatly captures the idea of the command. It looks at the context in which it is called and then does the right thing™. Most often, I highlight a region … Continue reading →

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Solution to the Two Challenges

Posted on 2012-05-04 by jcs

The other day, I presented two Elisp coding challenges. I specified Elisp because Irreal readers tend to like Emacs related posts. The down side of that is that several of you worried about bignums and other Emacs limitations. That wasn’t … Continue reading →

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Two Elisp Challenges

Posted on 2012-05-02 by jcs

I ran across a couple of nice interview questions and an interesting story over at Tanya Khovanova’s Math Blog. The two questions are: Given a list of integers from 1 to n but with one of the integers missing, write … Continue reading →

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Troubleshooting Emacs Libraries

Posted on 2012-04-29 by jcs

While trawling around the WikEmacs site today, I came across this page on troubleshooting that explained some commands that I wasn’t familiar with. The first two are helpful if you are trying to search out library problems. For example, if … Continue reading →

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TPK In Common Lisp

Posted on 2012-04-28 by jcs

Yesterday I wrote about the Trabb Pardo Knuth algorithm and gave an implementation in Emacs Lisp. Elisp allows an nice implementation but was a bit frustrating because the Elisp interpreter handles overflows internally and never signals an overflow condition. Therefore, … Continue reading →

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The Trabb Pardo Knuth Algorithm in Elisp

Posted on 2012-04-27 by jcs

The latest Programming Praxis Exercise is interesting. Back in 1973, Luis Trabb Pardo and Don Knuth published an algorithm that was meant to assess the power of a programming language. The algorithm was Ask for 11 numbers to be read … Continue reading →

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Decimalizing Latitude and Longitude

Posted on 2012-04-24 by jcs

Xah Lee has reintroduced a challenge from last year. Given a string of latitude/longitude is degrees, minutes, seconds, write a function that returns them as signed decimal numbers. That is, “37°26′36.42″N 06°15′14.28″W” → (37.44345 -6.253966666666667) I remember looking at this … Continue reading →

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A Key Sequence For revert-buffer

Posted on 2012-04-21 by jcs

The other day I was trawling through Aaron Hawley’s excellent Emacs Reference Sheet and came across the entry for【Ctrl+x Ctrl+v Return】saying “same as previous.” The previous entry was for revert-buffer. My first thought was “How did I not know this?” … Continue reading →

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The Emacs clean-buffer-list Command

Posted on 2012-04-17 by jcs

Some time ago, I enabled save-desktop-mode in Emacs and I’ve been really happy with it. I generally never close Emacs but sometimes I need to restart it for one reason or another or an OS upgrade requires me to reboot. … Continue reading →

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