Comments for What's In Peter's Head http://www.pchristensen.com/blog Peter Christensen's Blog Sat, 17 May 2008 02:49:04 +0000 http://wordpress.org/?v=2.5 Comment on Public Beta Open For “Ultimate N00b SLIME/Emacs Cheat Sheet” by Installing CLISP, Emacs, and SLIME on Windows XP » What’s In Peter’s Head http://www.pchristensen.com/blog/articles/public-beta-open-for-ultimate-n00b-slimeemacs-cheat-sheet/#comment-465 Installing CLISP, Emacs, and SLIME on Windows XP » What’s In Peter’s Head Fri, 16 May 2008 15:49:25 +0000 http://www.pchristensen.com/blog/articles/public-beta-open-for-ultimate-n00b-slimeemacs-cheat-sheet/#comment-465 [...] Emacs NOTE #2: Emacs has lots (and lots and lots) of keyboard shortcuts, many more than there are letters in the alphabet. Many of them require multiple keys or a sequence of keys called a “chord”. The two modifier keys used are Control and Alt (also called Meta). The common way to write chords is to use C- and M- for Control and Meta, so to run the command to close Emacs, you hold down Control and X, then let go, then hold down Control and C. This is written as C-x C-c. Sometimes a chord is followed by another letter or the name of a command. For instance, to undo, you hold Control and x, then let go and hit u. This is written as C-x u. Dashes mean press at the same time, space means let go. Easy! I made a cheat sheet for common commands in Emacs and SLIME. [...] […] Emacs NOTE #2: Emacs has lots (and lots and lots) of keyboard shortcuts, many more than there are letters in the alphabet. Many of them require multiple keys or a sequence of keys called a “chord”. The two modifier keys used are Control and Alt (also called Meta). The common way to write chords is to use C- and M- for Control and Meta, so to run the command to close Emacs, you hold down Control and X, then let go, then hold down Control and C. This is written as C-x C-c. Sometimes a chord is followed by another letter or the name of a command. For instance, to undo, you hold Control and x, then let go and hit u. This is written as C-x u. Dashes mean press at the same time, space means let go. Easy! I made a cheat sheet for common commands in Emacs and SLIME. […]

]]> Comment on Sleeping Too Much and Fighting With Emacs and ASDF by Installing CLISP, Emacs, and SLIME on Windows XP » What’s In Peter’s Head http://www.pchristensen.com/blog/articles/sleeping-too-much-and-fighting-with-emacs-and-asdf/#comment-464 Installing CLISP, Emacs, and SLIME on Windows XP » What’s In Peter’s Head Fri, 16 May 2008 15:48:56 +0000 http://www.pchristensen.com/blog/articles/sleeping-too-much-and-fighting-with-emacs-and-asdf/#comment-464 [...] week, I had been putting off setting up a CL/Emacs/SLIME environment from scratch ever since I had trouble getting ASDF to work with Lispbox. Every time I tried, I ran into some will-sapping problem like needing to find a good [...] […] week, I had been putting off setting up a CL/Emacs/SLIME environment from scratch ever since I had trouble getting ASDF to work with Lispbox. Every time I tried, I ran into some will-sapping problem like needing to find a good […]

]]> Comment on The Value is in the Experience by What Kind of Software Would People Actually Pay For? » What’s In Peter’s Head http://www.pchristensen.com/blog/articles/the-value-is-in-the-experience/#comment-458 What Kind of Software Would People Actually Pay For? » What’s In Peter’s Head Tue, 13 May 2008 18:37:11 +0000 http://www.pchristensen.com/blog/?p=227#comment-458 [...] See two update posts: “The Value in in the Experience” and “Music Operates Directly on Your Abstract Syntax [...] […] See two update posts: “The Value in in the Experience” and “Music Operates Directly on Your Abstract Syntax […]

]]> Comment on Ripping And Encoding Streaming RM, or How I Defeated RealPlayer by Peter http://www.pchristensen.com/blog/articles/ripping-and-encoding-streaming-rm-or-how-i-defeated-realplayer/#comment-457 Peter Tue, 13 May 2008 18:14:45 +0000 http://www.pchristensen.com/blog/?p=236#comment-457 Sharma, Sigh. I guess that's what I get for not reading directions. Well, my method still works generally for non-OCW streams. Thanks for the tip! Sharma,
Sigh. I guess that’s what I get for not reading directions. Well, my method still works generally for non-OCW streams. Thanks for the tip!

]]> Comment on Ripping And Encoding Streaming RM, or How I Defeated RealPlayer by Sharma http://www.pchristensen.com/blog/articles/ripping-and-encoding-streaming-rm-or-how-i-defeated-realplayer/#comment-456 Sharma Tue, 13 May 2008 18:12:24 +0000 http://www.pchristensen.com/blog/?p=236#comment-456 Actually, you have the option of saving OCW videos to your hard disk: http://mit-ocw-thai.eng.chula.ac.th/OcwWeb/Global/OCWHelp/help.htm#26 Actually, you have the option of saving OCW videos to your hard disk: http://mit-ocw-thai.eng.chula.ac.th/OcwWeb/Global/OCWHelp/help.htm#26

]]> Comment on MIT’s OpenCourseWare: Caveats by Ripping And Encoding Streaming RM, or How I Defeated RealPlayer » What’s In Peter’s Head http://www.pchristensen.com/blog/articles/mits-opencourseware-caveats/#comment-455 Ripping And Encoding Streaming RM, or How I Defeated RealPlayer » What’s In Peter’s Head Tue, 13 May 2008 17:43:41 +0000 http://www.pchristensen.com/blog/articles/mits-opencourseware-caveats/#comment-455 [...] known (and written about) MIT’s OpenCourseWare project for a while but never gone through any of the courses. [...] […] known (and written about) MIT’s OpenCourseWare project for a while but never gone through any of the courses. […]

]]> Comment on Updated Lisp Companies Page by Peter http://www.pchristensen.com/blog/articles/updated-lisp-companies-page/#comment-453 Peter Sat, 10 May 2008 12:48:05 +0000 http://www.pchristensen.com/blog/articles/updated-lisp-companies-page/#comment-453 Dan - I've seen and read your survey - I think it's one of the more important documents out there related to Common Lisp. Just an update - I recently added more companies and it's around 50 now. Dan - I’ve seen and read your survey - I think it’s one of the more important documents out there related to Common Lisp.

Just an update - I recently added more companies and it’s around 50 now.

]]> Comment on Music Operates Directly On Your Abstract Syntax Tree by Peter http://www.pchristensen.com/blog/articles/music-operates-directly-on-your-abstract-syntax-tree/#comment-452 Peter Sat, 10 May 2008 12:30:02 +0000 http://www.pchristensen.com/blog/?p=230#comment-452 Dan: Thanks for the tip - I'll definitely check out Stuff of Thought. Right now I'm working on <a href="http://www.amazon.com/o/asin/0671657135/pchristensen-20" rel="nofollow">Society of Mind</a> by Marvin Minsky. Another book I read a while ago and enjoyed was <a href="http://www.amazon.com/o/asin/1591025117/pchristensen-20" rel="nofollow">Beyond AI</a> by J. Storrs Hall. It was a good high level overview of the history and potential of AI. I've tried Pandora and it is a pretty amazing music discovery service. Dan: Thanks for the tip - I’ll definitely check out Stuff of Thought. Right now I’m working on Society of Mind by Marvin Minsky. Another book I read a while ago and enjoyed was Beyond AI by J. Storrs Hall. It was a good high level overview of the history and potential of AI.

I’ve tried Pandora and it is a pretty amazing music discovery service.

]]> Comment on Updated Lisp Companies Page by Daniel Weinreb http://www.pchristensen.com/blog/articles/updated-lisp-companies-page/#comment-451 Daniel Weinreb Sat, 10 May 2008 12:04:39 +0000 http://www.pchristensen.com/blog/articles/updated-lisp-companies-page/#comment-451 Have you seen my survey of Common Lisp implementations? People interested in your list might also be interested in the survey (which already links to your list). See: http://common-lisp.net/~dlw/LispSurvey.html Have you seen my survey of Common Lisp implementations? People interested in your list might also be interested in the survey (which already links to your list). See:

http://common-lisp.net/~dlw/LispSurvey.html

]]> Comment on Best Quote About Lisp (That’s No Longer Valid) by Daniel Weinreb http://www.pchristensen.com/blog/articles/best-quote-about-lisp-thats-no-longer-valid/#comment-450 Daniel Weinreb Sat, 10 May 2008 12:01:48 +0000 http://www.pchristensen.com/blog/articles/best-quote-about-lisp-thats-no-longer-valid/#comment-450 Python and Ruby and Java have borrowed a lot of good ideas from Lisp. There are things about Lisp that used to be novel and nearly unique, such as garbage collection, that have moved into the mainstream. So even if Lisp is not one of the prominent languages in use today (we're working on that!), it has had a lot of influence. About "special purpose", a great thing about Lisp is that you get the best of both worlds. Common Lisp is a general purpose language. But when you want/need a special purpose language, you can just build it in Common Lisp, using macros and other facilities. That's hugely faster than writing a whole new language system from scratch! A lot has been written about these "little languages" and it's one of the most important things about Common Lisp both in theory and in practice. At my shop (ITA Software), we use C primarily when we have to do a whole lot of bit-level manipulation - I'm talking about huge amounts, where the performance benefit of C's special-purpose ability to do this is overwhelming. We also have used C for writing Apache modules and stuff like that. But it's the language of last resort. We use Java and Python a lot, too, though there are more lines of Common Lisp than anything else. Python and Ruby and Java have borrowed a lot of good ideas from Lisp. There are things about Lisp that used to be novel and nearly unique, such as garbage collection, that have moved into the mainstream. So even if Lisp is not one of the prominent languages in use today (we’re working on that!), it has had a lot of influence.

About “special purpose”, a great thing about Lisp is that you get the best of both worlds. Common Lisp is a general purpose language. But when you want/need a special purpose language, you can just build it in Common Lisp, using macros and other facilities. That’s hugely faster than writing a whole new language system from scratch! A lot has been written about these “little languages” and it’s one of the most important things about Common Lisp both in theory and in practice.

At my shop (ITA Software), we use C primarily when we have to do a whole lot of bit-level manipulation - I’m talking about huge amounts, where the performance benefit of C’s special-purpose ability to do this is overwhelming. We also have used C for writing Apache modules and stuff like that. But it’s the language of last resort. We use Java and Python a lot, too, though there are more lines of Common Lisp than anything else.

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