InspireData: How We Did It In Lisp Jeremy Jones

A very whizzy, very polished shrinkwrapped Windows and OSX application written in Common Lisp that actually sells well (> 80k seats sold). 12MB of lisp code in 284 source files. Key learnings: specification is hard so incremental refinement is necessary, and “Lisp supports this better than anything I know”. Key quote: “The world needs to use more lisp.”

FEMLISP Nicolas Neuss

A system for solving partial differential equations using finite element methods. 30K lines of lisp code. Key quality: the stability of the base language - “I learned Common Lisp and I’m still up-to-date!” FEMLISP currently has one user, and there seems to be some reluctance to increase that number…

Using Common Lisp For Large Internet Systems Stefan Richter

freiheit.com is a 60 person company that builds large internet systems in 98% Java with the rest being C and C++. (See also  h.w.a.) While it is easy to make mistakes, it is well known how to build large internet systems (1 million users and above). The various bits and pieces are usually in Java, but almost everything could be done in CL today, and certainly tomorrow with a bit of effort. The talk seemed to diverge at this point. On the one hand we should be encouraging people to use lisp in web programming (use weblocks and blog about it; “write a book”). On the other hand we should be introducing call-cc into CL, because (despite seeming to contradict many of the best practices for building scalable internet systems) they are really cool for web apps…

PWGL Killian Sprotte

Killian had a great two-hour presentation on the impressive PWGL/Patchworks with OpenGL musical composition and analysis tool (or “Programming with Boxes”). Unfortunately he only had 45 minutes to present it. Certainly the talk with the highest “wow” factor, this is one to download and try out, not to read (or write) about.

ECL = (not only) Embeddable Comman Lisp Juan José Garcia Ripoll

A presentation of the past, present and future of ECL. A pretty convincing demonstration that ECL is not stripped down, but is a fully fledged Common Lisp (to mix my metaphors).

Selvaag House Designer Kristoffer Kvello

Using Knowledge Based Engineering and CL to automatically design buildings. Six full-time lisp programmers. Impressive application. I’ve always thought lisp uniquely suited to automated compliance applications - turns out I was right. Key observation: “Lisp: all good, no problems.”

HPC Platform Marc Battanyi

Subtitled “CL + FPGA = The Ultimate Processing Platform (or the Worst Case of NIH Syndrome)”, this presentation was another that suffered from being too long for its timeslot. All is forgiven, however, because Marc’s humour is bone dry.

? Ken Tilton

Ummm. This was Cells redux redux. I think. As a proponent (exponent?) of Screenshot Driven Development I can’t disagree with Kenny’s decision to concentrate on (as he put it) “stupid pet tricks”, but with no discernable structure, narrative or point, I really didn’t feel I learned anything…

All in all, the talks were great, the crowd interesting, the venue unique, and, while I won’t be at ELS in Bordeaux, I’m definitely intending to be at ILC ‘09 at MIT (driven by Dan Weinreb - who was in Amsterdam - and Guy Steele - who wasn’t). I might even actually have done some lisping by then…

Down my end of the table(s) talk was about R6RS and the social psychology of standardisation; ARC and the rôle of Paul Graham in the (Common) Lisp community; theoretical physics and the bandwidth requirements of CERN; performance characteristics of Bigloo, SBCL and Chez Scheme; why developing in Schemes other than Scheme48 is painful and the wonders of Slime; and the mystery of where all the lispers maintaining the Swiss International Airlines Limited application have gone.

I made a particularly unconvincing argument for the wonders of CLIM and Climacs. Must do better!

I was the first to leave, so things might well have broken up acrimoniously by the end of the evening, but judging on what I saw and heard I would have to say that ZSLUG has a great future ahead of it.

No one replied.

So I had to do it myself. Startlingly simple for my humble needs, the solution consists of a key-code invoking a macro which shells out to cscript running a Jscript program. The slightly interesting point is that this last is generated by Parenscript, and looks like so:

(defvar wd-app (*get-object "" "Word.Application"))
(defvar a-doc wd-app.*active-document)

(defun de-number ()
  (let ((cnt a-doc.*lists.*count))
    (dotimes (i cnt)
      (let ((lst (slot-value (a-doc.*lists 1)
                             '*range.*list-format)))
        (lst.*convert-numbers-to-text 3)))))

This is obviously far from being great style, but it gets the job done and has me wondering about all the other things I could be doing with parentheses…

VBacs - give it a go if you’re sentenced to Word.

PS. Does anyone have a programmatic way to replace the furshlugginer automatic numbering in a Word document with its textual equivalents? (That is, replace the automatically inserted numbering “1.13″ with the text “1.13″.)

To examine the differences Waters used two simple functions, maplist-nreverse:

(defun maplist-nreverse (f list)
  (do ((sub list (cdr sub))
       (r nil (cons (funcall f sub) r)))
      ((null sub) (nreverse r))))

and maplist-rplacd:

(defun maplist-rplacd (f list)
  (let ((r (cons nil nil)))
    (do ((sub list (cdr sub))
	 (end r (let ((x (cons (funcall f sub) nil)))
		  (rplacd end x)
		  x)))
	((null sub) (cdr r)))))

Timing the functions using #'identity as the map function he got the following results (Lucid Common Lisp on an HP-730):

(where the numbers represent computation time in microseconds per cons created).

For no real reason I replicated this on an Intel Core2 T7200 2.0GHz running Win32 and sbcl 1.0.6:

(where the numbers represent computation time in microseconds per element of the input list).

Although the trend seems to be for the rplacd version to be slightly faster, the differences seem minor, and we might as well adopt Waters’ recommendations:

In closing I would like to note that the very best thing to do is to avoid writing code that conses lists altogether. Whenever possible, you should use standard parts of Common Lisp that do the consing for you. In particular, you should use functions like replace, map, reduce, remove, union, etc. whenever they are appropriate. Beyond this, you should take advantage of looping macro packages such as loop and Series.

We will issue specific commands with a set of push buttons, turn functions on and off with switches, indicate position information and point to existing drawing parts with the light pen, rotate and magnify picture parts by turning knobs, and observe the drawing on the display system.

Where are my knobs and buttons? Why is the great advance of recent decades in widely available physical human-computer interaction the click-wheel mouse?

Sutherland opens his thesis by observing:

Heretofore, most interaction between men and computers has been slowed down by the need to reduce all communication to written statements that can be typed; in the past, we have been writing letters to rather than conferring with our computers.

Isn’t it time the epistolary model of interaction evolved?^1,2

2. Yes, I am being deliberately provocative - this is the web - but I can imagine zipping through a document accepting and rejecting edits with my PS2 control being a lot more productive (and fun) than the mouse+keyboard experience.

Your favourite lisp(s) + emacs + Slime (+ paredit) constitute a fabulous development environment that is widely used, and therefore widely supported, on #lisp. Eschewing this environment for something else will make it far harder for people to understand your problems and (if you ask nicely, and intelligently) help you with them.

(I also find it telling that when the smart folks who started developing lisp had the time and energy to build editors they built emacsen.)

However, if you really can’t stand emacs (perhaps because of a childhood incident with Richard Stallman, a wasp’s nest and a jar of manuka honey), you could use plain Vi (and give up the wonders of Swank) or Cusp, if you’re an Eclipse fan.

But don’t come running to us when something goes wrong.

A2

“I want to learn Russian but I can’t be bothered with all the funny characters.”

* “FEP” = Frequently Expressed Predjudice

By following the instructions for your lisp implementation:

• sbcl - (sb-ext:save-lisp-and-die filename :executable t)
• clisp - (ext:saveinitmem filename :save-executable t)
• OpenMCL - (require "COCOA-APPLICATION")
• ECL - (c:build-program ...)
• Allegro - (generate-executable ...)
• LispWorks - (deliver ...)

These last two have a whole host of bells and whistles (including, in the case of LispWorks, a tree-shaker), but require the paid-for versions. (You should also check their royalty requirements.)

A2

Why would you want to? Really? What commonly distributed systems in this day and age come in a single executable file, except as a delivery mechanism that subsequently sprays various libraries, databases and settings mechanisms around your filesystem?

I say - No. The proper place for the Control key is not “on the home row” but on each side of the Space Bar, where Tom
Knight and the mothership intended them to be. And outside the Control keys should be the Meta keys, and outside them should be the Super keys, and finally the Hyper keys. This allows for what I think is a very natural way of typing key-chords - the modifiers with one hand, and the letter/symbol with the other. These are, after all, the sorts of keyboards on which Emacs was first developed.

How you do this will depend on your OS and your keyboard. For Windows, you might like to start here or here.^* In OSX you can look in System Preferences > Keyboard & Mouse > Modifier Keys. For Linux, there are a thousand xmodmap and xkb tutorials…

The other keyboard reconfiguration I recommend is, where possible, to put the parentheses on unshifted keys (swapping with the [square] brackets works on some keyboards). Of course, if, like me, you live/work in a locale with all manner of chicken scratchings on top of proper latin letters this may not be possible or convenient. (Eric Naggum’s more radical approach can be seen here.)

So, my advice for Emacs (Climacs, VBacs) newbies would be: don’t swap Caps-Lock and Control, swap Alt, Ctrl, Windows, Application, AltGr…

1. Fire up regedt32.exe and navigate to HKEY_CURRENT_USER\Keyboard Layout.
2. Create a new entry Scancode Map (using Edit > New > Binary Value).
3. Edit the new entry (using Edit > Modify Binary Data) to contain the following:

       0000   00 00 00 00 00 00 00 00
       0008   04 00 00 00 1D 00 38 00
       0010   38 00 5B E0 5B E0 1D 00
       0018   00 00 00 00

   The table is in little-endian form. The first 8 bytes are header (all zeroes). The next four bytes contain the count of entries (4, including the sentinel). The three following four byte entries swap Left Alt (0x38) with Left Ctrl 0x1D), Left Win (0xE058) with Left Alt, and Left Ctrl with Left Win. The last 4 bytes are a null terminator/sentinel.

4. Close up, log off, log on, and enjoy.

If you did this, of course, it would be entirely at your own risk.