Category Archives: Programming

The WikEmacs Elisp Cookbook

Posted on 2012-04-26 by jcs

I stopped by WikEmacs today to see how the site was progressing. It looks pretty nice and has obviously seen some hard work by its contributors. Being me, I immediately went to the Emacs Lisp Cookbook to see how it … Continue reading →

Posted in Programming | Leave a comment

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 →

Posted in Programming | Tagged , | 2 Comments

Elisp Input With History And Completion

Posted on 2012-04-13 by jcs

Xah Lee has a nice post up dealing with getting user input with completion and history in Emacs. I usually just use interactive with “s” or possibly “f” or “F” but Lee shows us a better way. Did you know … Continue reading →

Posted in Programming | Tagged , | 1 Comment

Guile Fail

Posted on 2012-04-10 by jcs

I have a set of guile scripts that I use to produce a rarely needed report. Today I tried to run the report and guile failed because it couldn’t find libltdl. No problem, I thought, it probably got wiped out … Continue reading →

Posted in Programming | Tagged | Leave a comment

Common Lisp FAQ

Posted on 2012-04-06 by jcs

Nikodemus Siivola has updated his Common Lisp FAQ. It’s a nice resource for new Lispers and well worth a read. You might also want to check out his home page; he’s got links to many of his projects and some … Continue reading →

Posted in Programming | Tagged | Leave a comment

Slicing Words With Elisp

Posted on 2012-04-04 by jcs

I was playing around with another ITA hiring puzzle today and needed to “slice” a sequence of words. That is, I wanted to form a list of strings consisting of the first letters of each word, the second letters of … Continue reading →

Posted in Programming | Tagged , | 1 Comment

Solution To The Add-A-Gram Challenge

Posted on 2012-04-03 by jcs

Last week, I issued a challenge to solve the Add-A-Gram puzzle using Emacs and Elisp. The puzzle statement is here. This is an interesting problem that’s easy to get wrong.The solution seems straightforward: Start with a 3-letter word (car, say). … Continue reading →

Posted in Programming | Tagged , , | Leave a comment

Two From Garret

Posted on 2012-04-02 by jcs

I was trawling through Ron Garret’s site (see yesterday’s post) and came upon two excellent short papers. The first, The Idiot’s Guide to Special Variables discusses the difference between lexical and special (or dynamic) variables. The second, The Idiot’s Guide … Continue reading →

Posted in Programming | Tagged | Leave a comment

Lisp At JPL

Posted on 2012-04-01 by jcs

A long time ago, I read and enjoyed Ron Garret’s story of using Lisp at the Jet Propulsion Laboratory. Now, he retells the story in a Google Talk that is well worth watching. Part of the story explains how they … Continue reading →

Posted in Programming | Tagged | Leave a comment

Clozure Common Lisp 1.8

Posted on 2012-03-31 by jcs

I took advantage of the weekend to upgrade my machines to Clozure CL 1.8. As usual, installation was a snap. Just get the distribution with SVN: svn co http://svn.clozure.com/publicsvn/openmcl/release/1.8/darwinx86/ccl for Mac OS X and then ccl64 -n ? (ccl:rebuild-ccl :full … Continue reading →

Posted in Programming | Tagged | Leave a comment