The culture of “air guitar”: http://tekkie.wordpress.com/2008/06/10/the-culture-of-air-guitar/

That got me thinking, the people that we all think of as the “really good programmers”, are they Jimi Hendrix

or just Thad Jarvis?

I read up on CALL/CC and DYNAMIC-WIND last week after I got my ass seriously kicked by Edwin’s terminal code. I think I’m starting to grok it now, but I’m not sure if I know how to write that code all by myself.

I sure hope this is not just more Air Guitar gesturing.

That’s all well and good, but let’s look at the close up:

Hong Kong island, Kowloon, and Lantau Island are totally missing.

For those not in the know, here’s a map of Hong Kong:

It’s disappointing that even a supposedly ‘classy’ joint like Apple gets simple things like this (ahem, geography) wrong.

Another case in point: CNN and France.

Now that I’ve been programming (exclusively) in Scheme for the past two years, I realized that I have slowly — but surely — learned to accept and embrace one of the most controversial surface syntax in a programming language: the S-Expression.

The criticism to sexpr syntax are numerous, and most of them can be seen as silly once you have gotten used to it, however here lies the problem: most people never get past their initial reaction to sexpr. They see the parenthesis and just freeze up.

Lispers and Schemers are the first to point out the advantages to having such a syntax: it’s simple, easy to understand and parse, and concise. In the end, however, it actually all boils down to just one single thing: We know how to write awesome macro systems with a sexpr surface syntax.

And this is all well and good.

However, now that we have decided to stick with this syntax, and we have used it to our advantages to write many wonder macro systems, what else can we do with this decision?

In Scheme, when you write down a list of four elements, beginning with the word list like this:

(list 'apple 'banana 'cactus) => '(apple banana cactus)

You get a list with three elements. You can query it in the following ways:

(list?  '(apple banana cactus)) => #t
(length '(apple banana cactus) => 3
(first  '(apple banana cactus))   => apple
(last   '(apple banana cactus))   => cactus

So you are able to find out that it is a list, and from that, its length and its first and last element.

This is elementary stuff, and anyone learning Scheme would know this by the end of their first week in class. However, what about this?

(define hello (lambda () (display "Hello")))

This is again a list, of three elements. The first element is define, then hello and last is another list (which begins with the word lambda).

In R5RS Scheme, there’s virtually nothing you can do to query this structure. The most that you can do, as far as I know, is with MIT Scheme’s procedure? and procedure-arity procedures, which corresponds to list? and length for lists.

Wouldn’t it be cool if one could manipulate Scheme code (procedures) as easily as one could manipulate Scheme data (lists, vectors)? I don’t mean that there should be a procedure-car and procedure-cdr, but something more specific, like procedure-name and procedure-body. This can be extended to other constructs as well. Given:

(if (list? l) (length l) 0)

We could have

(expression-type? ##) => <if-expression>
(if-test          ##) => (list? l)
(if-then-clause   ##) => (length l)
(if-else-clause   ##) => 0

Why hasn’t this been done before? I did some literature research, and am surprised to see so little on this topic.

Recently, I came across Charlotte Herzeel’s talk at the S3 workshop, but I think she’s going about it in the wrong way because she’s only thinking about the manipulation of code as lists, using variations of car and cdr instead of something with more specific semantics attached to it. Perhaps her background in Common Lisp (instead of Scheme) maybe have something to do with that.

相對不發一言　似是你共我有了默契

永不要幼稚的罵戰

但表情彼此表情悄悄地暗示

這是冷戰

我愛你你也愛我

這個你我過去也聽過說過

破裂過厭棄過怨過傷過變過

你我卻永遠怕說破

冷戰再冷戰再冷戰

一錯再錯我卻愛上這個錯

怪責你揭破你放棄你可會使我好過

Shelley Young: you know
Shelley Young: your blog makes you look like a commie

Just so you know, I’m not a commie.

When I got back to the US last spring, I went to talk to Olin Shivers about my idea of implementing R5RS on top of Alan and Ian’s COLA runtime. While I think that is still a good idea, it didn’t pan out then and I moved on to work on something else.

Instead I have been working with Olin to restart the Scheme Underground effort that has (pretty much) been abandoned since the early 90s. Our initial plan was to work on a nice interactive shell that’s based on Olin’s work on scsh, however that idea was abandoned after realizing that the Tüebingen crew already did something similar with Commander S. However, with its customizable viewers, Commander S is actually quite a bit more than just a normal interactive shell, so I still think it’s interesting to implement our original (simpler) concept.

To get up to speed on Scheme, I learned about Termcap and Terminfo and ported Paul Foley’s terminfo.lisp to Scheme. I also took another Common Lisp project, Linedit, as inspiration and wrote my own Scheme version from scratch.

Lately, I have been working on porting MIT Scheme’s Edwin editor to Scheme48. I hope to get a terminal-based text-only version done before the beginning of the summer. Wish me luck.

I took Srinig’s Fluid Blue theme and sinified it by changing it to use the reddish colors from the Tango Project’s color palette. I’m called my derived theme Fluid Red, it’s available in my Git repository.

Here’s some Scheme code for all of you fans out there:

(define-record-type keystroke
  (%make-keystroke %value %meta?)
  keystroke?
  (%value char-value)
  (%meta? meta?))

(define-record-discloser keystroke
  (lambda (k)
    `(Keystroke ,(keystroke->sexpr k) ,(keystroke-hash k) )))

(define (parse-key form)
  (if (list? form)
      (let ((tag (car  form))
            (val (cadr form)))
        (case tag
          ((control) (%control  (parse-key val)))
          ((meta)    (%meta     (parse-key val)))
          ((key)     (%key     val))
          (else      (error "This is not a valid key form " tag))))
      (%key form)))

I saw this clip from News Hounds from Hannity and Colmes, and my first thought was:

If that were not the Iranian govt lynching an Iranian, but the American govt doing it to an “Islamo-fascist”, wouldn’t Hannity approve of it completely?

Here’s the clip, see it for yourself:

I haven’t been doing much – other than playing Wii tennis, I have mostly been staying at home. Yesterday, I decided to venture out to the bigger world that is Central, Hong Kong.

I went to the new shiny mall in town, the IFC (giant penis-shaped building by the waterfront) and strolled around. Everything in that mall seemed über expensive. I didn’t feel comfortable at all walking into one of the stores wearing my ratty cardigan from American Apparel and a tote bag that says ‘ILLEGAL DRUGS’.

To escape it all, I ended up sitting around at a McDonalds.

Afterwards, I met up with my mom at c!ty’super, the local Whole Foods-like supermarket. While waiting in line, I saw this caucasian woman in her late 20s holding a shopping basket with a box of DeCecco pasta and other groceries on one hand, and a hastily printed copy of Rachael Ray’s You won’t be Single for Long vodka cream pasta from the Food Network on her other hand.

I think I’m the only one in the checkout line who noticed it. If she were in the US, I think she probably wouldn’t dare to put her new recipe in such proud display.