Tag Archives: Emacs-lisp

Emacs Hash Tables

One of the most useful data structures in Computer Science is the hash table. I’ve been using them for my entire career and have implemented close to a hundred instances in several languages. That’s not as necessary these days as … Continue reading

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Maintaining My Blog Post Queue

Because inspiration doesn’t necessarily strike on demand, I like to stay a few posts ahead. For the last year, my procedure was to push a completed post to the site as a draft and then publish it when I was … Continue reading

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A O(n) Solution to the Last Elisp Challenge

As I mentioned in the post, my An Elisp Challenge post was suggested by this Programming Praxis post. The next Programming Praxis post was a followup that discussed Booth’s Algorithm, which calculates how many left rotations a string must undergo … Continue reading

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My Solution to the Elisp Challenge

Here’s my solution to the recent Elisp challenge. It’s easy to be seduced by the notion of rotating one sequence to see if it’s equal to the other. That would work but the rotation is pretty expensive and the solution … Continue reading

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An Elisp Challenge

Here’s a simple Elisp challenge suggested by a problem from by ProgrammingPraxis. We call one string a cycle of another if one string can be transformed into the other by a rotation of the characters. Note that this means They … Continue reading

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A Full Screen Eshell

Almost all of my tube time is spent in 4 programs: Emacs; Safari; Reeder; and Mail, roughly in that order. Naturally, I try to stay in Emacs as much as I can. In particular, I’ve long bound 【Ctrl+c s】 to … Continue reading

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Elisp

No wonder it’s so hard to learn.

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Emacs Batch Text Processing

Xah Lee has a page up on batch text processing with Emacs. The page is a recapitulation of several tips that Lee has published before. These tips were very helpful to me when I was trying to learn the Elisp … Continue reading

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A Xah Lee Challenge

Over at ergoemacs.org, Xah Lee posses the following challenge: Find a simple and general method to create the following text. (global-set-key (kbd “<menu> g a”) “A”) (global-set-key (kbd “<menu> g b”) “B”) (global-set-key (kbd “<menu> g c”) “C”) (global-set-key (kbd … Continue reading

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Symbols in Emacs Lisp

One of the hardest things for Lisp newcomers to understand is symbols. They look tantalizingly like variables from other languages and, indeed, they are often just that. But, as the new Lisper soon discovers, they are much more. Xah Lee … Continue reading

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