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Aardvark and Bandicoot, Chapter 19

Thursday 19 May 2016, 12:25

In which a Parable is Related and Betting Strategies are Considered

[first chapter] | [all in this series]

Aardvark: Friend Bandicoot, I heard an interesting story recently. Perhaps you might find it edifying.

Bandicoot: Oh, goody! I do like stories, Friend Aardvark.

Aardvark and Bandicoot, Chapter 18

Wednesday 18 May 2016, 12:25

In which there is an Inquiry into What Counts, and into the Aardvark's Commitment to the Cause

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, I've got the module passing the test suite now!

Aardvark: Really?

B: Yes.

A: And it's really the module passing the test suite, not one of your school chums hiding inside the computer?

B: Uh-huh. Well, almost.

Aardvark and Bandicoot, Chapter 17

Tuesday 17 May 2016, 12:25

Some Clinical Consequences of Introjection

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, I've given a lot of thought to our conversation the other day about the ontology of software engineering.

Aardvark: I had hoped you would.

B: It took me a while to see it, but I think your point about no one single test case being necessary is in fact correct.

Aardvark and Bandicoot, Chapter 16

Monday 16 May 2016, 12:25

Studies in Ontology, with a Hint of Romance

[first chapter] | [all in this series]

Aardvark: Friend Bandicoot, do you know what a formal ontology is?

Bandicoot: Yes, Friend Aardvark. I learned about them in library school.

Aardvark and Bandicoot, Chapter 15

Sunday 15 May 2016, 12:25

Introducing the Mechanical Australian

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, I've implemented the double-double feature you wanted in the parser.

Aardvark: Again, Friend Bandicoot?

B: Well, you keep telling me to re-do it.

Aardvark and Bandicoot, Chapter 14

Saturday 14 May 2016, 12:25

In which a Feature is Implemented, but At What Cost?

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, Friend Aardvark! I've added that extra double-double feature you wanted in the parser!

Aardvark: Really?

B: Yes!

A: Really really?

B: Of course!

A: Not just "almost," Friend Bandicoot?

Aardvark and Bandicoot, Chapter 13

Friday 13 May 2016, 12:25

In which we Accept our Limitations with Humility

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, Friend Aardvark! I've added that extra double-double feature you wanted in the parser!

Aardvark: Really?

B: Yes!

A: Really really, Friend Bandicoot?

B: Of course! Well. Almost.

A: I see.

Aardvark and Bandicoot, Chapter 12

Thursday 12 May 2016, 12:25

In which a Blow is Struck for Feminist Scholarship

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, I implemented the double-double feature you wanted.

Aardvark: That's excellent, Friend Bandicoot.

B: Yes.

A: So, the test suite passes now, right?

B: Well... actually, I did something even better.

A: Oh.

Aardvark and Bandicoot, Chapter 11

Wednesday 11 May 2016, 12:25

In which Priorities have been Implemented

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, Friend Aardvark!

Aardvark: Good morning, Friend Bandicoot.

B: I implemented the optional extra double-double feature!

A: You mean, the module can finally add two plus two?

B: That's what I said.

Aardvark and Bandicoot, Chapter 10

Tuesday 10 May 2016, 12:25

In which Priorities are Set

[first chapter] | [all in this series]

Bandicoot: Good morning, Friend Aardvark!

Aardvark: Good morning, Friend Bandicoot.

B: I'm wearing my programming trousers again today.

A: I can see that you are.

B: Well?

Aardvark and Bandicoot, Chapter 9

Monday 9 May 2016, 12:25

In which a Debt is Paid

[first chapter] | [all in this series]

Post-It note on the Aardvark's office door: Home sick today. Migrane.

Aardvark and Bandicoot, Chapter 8

Sunday 8 May 2016, 12:25

In which a Post-Mortem Offers Valuable Insight

[first chapter] | [all in this series]

Aardvark: Good afternoon, Friend Bandicoot. I'm sorry to be late for this meeting.

Bandicoot: That's quite all right, Friend Aardvark. Is your head feeling better?

A: No. But we need to get this module out the door anyway, so I'll go be sick some other day. I spent most of this morning going through the test suite trying to figure out what's wrong with your code, and I think I've at least got some idea -

B: But there's nothing wrong with the code. You saw me demo it yesterday.

Aardvark and Bandicoot, Chapter 7

Saturday 7 May 2016, 12:25

In which a Demonstration Begins Well, and Concludes

[first chapter] | [all in this series]

Aardvark: Good morning, Friend Bandicoot. I trust you slept well?

Bandicoot: Very well, thank you, Friend Aardvark. It was most restful knowing I'd completed the project and wouldn't have to do any more work on it. Do you have new glasses today?

A: Yes, these are my demonstration spectacles.

B: Very appropriate to the occasion!

Aardvark and Bandicoot, Chapter 6

Friday 6 May 2016, 12:25

In which Concern is Expressed for One's Health

[first chapter] | [all in this series]

Aardvark: Good morning, Friend Bandicoot.

Bandicoot: Good morning, Friend Aardvark!

A: I'm surprised to see you here so early. Usually, you don't come in until just before lunch.

B: I was here all night!

Aardvark and Bandicoot, Chapter 5

Thursday 5 May 2016, 12:25

In which there is No More Progress, and a Management Decision is Made

[first chapter] | [all in this series]

Aardvark: Are you almost finished with that module for evaluating expressions?

Bandicoot: Yes! I have your module for parsing strings 80% complete!

A: Friend Bandicoot...

Aardvark and Bandicoot, Chapter 4

Wednesday 4 May 2016, 12:25

In which there Has been a Little More Progress, but Just a Little

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Aardvark: Friend Bandicoot, where do you stand with the expression evaluation module?

Bandicoot: I'm about 80% finished with the expression parser, Friend Aardvark. It's fun! I do like parsing.

Aardvark and Bandicoot, Chapter 3

Tuesday 3 May 2016, 12:25

In which Progress is Reported

[first chapter] | [all in this series]

Aardvark: Friend Bandicoot, how is that expression evaluator coming along?

Bandicoot: Oh, you mean the parser? It's about 75% complete, Friend Aardvark.

Aardvark and Bandicoot, Chapter 2

Monday 2 May 2016, 12:25

In which Some Points are Clarified, but One is Left Unanswered

[first chapter] | [all in this series]

Bandicoot: Friend Aardvark, Friend Aardvark!

Aardvark: Oh, good morning, Friend Bandicoot. I see you're wearing your programming pants again today.

B: Trousers.

A: What?

Aardvark and Bandicoot, Chapter 1

Sunday 1 May 2016, 12:25

"Ah, why, ye Gods! should two and two make four?"
- Alexander Pope, "The Dunciad"

In which a Project is Initiated

Bandicoot: Good afternoon, Friend Aardvark. I trust you're well?

Aardvark: Yes, thank you, Friend Bandicoot. Are you ready to do some software engineering?

Crowdfunding for LambdaConf

Friday 1 April 2016, 00:12

A "tech conference" called LambdaConf, after a blind reviewing process, accepted a technical presentation proposal from someone who had written about unpopular views on politics. Pressure groups demanded the conference exclude him; when the conference organizers decided not to do so, the pressure groups campaigned to have corporate sponsors withdraw support. Much to their discredit, most of the corporate sponsors did in fact do so. A "crowdfunding" campaign has been organized to replace the money those sponsors could have provided. I have donated, and I hope you will as well.

Mountain-climbing addresses for code lines

Wednesday 25 November 2015, 03:59

I found an interesting problem while working on a test case generator for the Tsukurimashou Project. The thing is that I'd like to assign an identifying code, which I will call an address, to each line of code in a code base. It's to be understood that these addresses have nothing to do with machine memory addresses, and they need not be sequential; they are just opaque entities that designate lines of code. Anyway, I would like lines of code to keep the same addresses, at least probabilistically, when the program is modified, so that when I collect test information about a line of code I can still keep most of it after I update the software.

Kleknev: a coarse-grained profiler for build systems

Monday 11 March 2013, 19:12

When I was preparing the Tsukurimashou 0.7 release, I had to build the entire package several times from scratch, to verify that all the necessary pieces really were included in what I was preparing to ship. When I run the build on my development machine it normally re-uses a lot of previously-built components, only updating the parts I have recently changed. That kind of incremental compilation is one of the main functions of GNU Make. But if I'm shipping a package for others to use, it has to work on their systems which don't have a previous history of successful builds; so I need to verify that it will actually build successfully in such an environment, and verifying that means copying the release-candidate package into a fresh empty directory on my own system and checking that the entire package (including all optional features) can build there.

Tsukurimashou is a big, complicated package. It's roughly 92,000 lines of code, which may not sound like so much. For comparison, the current Linux kernel is about 15,000,000. Tsukurimashou's volume of code is roughly equivalent to an 0.99 version of Linux (not clear which one - I couldn't find numbers I trusted on the Web just now, and am not motivated to go downloading old kernel sources just to count the lines). However, as detailed in one of my earlier articles, Tsukurimashou as a font meta-family is structured much differently from an orthodox software package. Things in the Tsukurimashou build tend to multiply rather than adding; and one practical consequence is that building from these 92,000 lines of code, when all the optional features are enabled, produces as many output and intermediate files and takes as much computation as we might expect of a much larger package. A full build of Tsukurimashou maxes out my quad-core computer for six or eight hours, and fills about 4G of disk space.

So after a few days of building over and over, it occurred to me that I'd really like to know where all the time was going. I had a pretty good understanding of what the build process was doing, because I created it myself; but I had no quantitative data on the relative resource consumption of the different components, I had no basis to make even plausible guesses about that, and quantitative data would be really useful. In software development we often study this sort of thing on the tiny scale, nanoseconds to milliseconds, using profiling tools that measure the time consumption of different parts of a program. What I really wanted for my build system was a coarse-grained profiler: something that could analyse the eight-hour run of the full build and give me stats at the level of processes and Makefile recipes.

I couldn't find such a tool ready-made, so I built one.

Where do I draw the line?

Monday 21 January 2013, 14:49

It's a very common pattern in the Han writing system that a character will be made of two parts that are themselves characters, or at least elements resembling characters, placed one above the other or one next to the other. For instance, 音 (sound) can be split into 立 (stand up) above 日 (day); and 村 (village) can be split into 木 (tree) next to 寸 (inch). This kind of structure can be nested, as in 語 (language). One can do a sort of gematria with the meanings, (what exactly is the deep significance of "village = tree + inch"?) but that's not the direction I'm interested in going today. Here's the thing: in the Tsukurimashou project, these two ways of constructing characters each correspond to a piece of code that's invoked many times throughout the system, and I thought it would be interesting to look at how often the different parameter values are used.

GIMP 2.8 versus FontForge

Saturday 19 May 2012, 10:58

A few days ago, I ran Arch Linux's update process and it pulled down and installed a new version of GIMP, version 2.8. This version incorporates some changes in the user interface which apparently were under development for a long time, but only very recently finally put into the "stable" distribution stream.

The one that interests me may appear on the surface to be very small, but it is and is meant to be a really significant shift in the entire definition of what GIMP is. GIMP used to be, as the name "GNU Image Manipulation Program" implies, an image editor. With version 2.8, GIMP has become an XCF file editor with the ability to read and write other formats.

Now on Github too

Tuesday 13 March 2012, 11:04

I took the plunge and created an account on the world's worst Internet dating site. This is mostly so that I can participate in the KanjiVG project, which has decided to host there; git and thereby Github remain not my favourite systems. However, I've established a mirror of Tsukurimashou in my new Github space, so people who do like git and Github can find it there now too.

Testing with Autotools, Valgrind, and Gcov

Saturday 4 February 2012, 09:27

I only have limited faith in software testing, partly because of my lack of faith in software engineering in general. Most professionally-written code is crap, and the more people use "methodologies," the worse their code seems to be. I'm inclined to think that the best way to remove bugs from code is to not put them in in the first place. Nonetheless, writing tests is fun. It's an interesting way to avoid doing real work, and some of you might enjoy reading about some test-related things I tried on a couple of my recent projects.

Distributed version control is not my favourite technology

Wednesday 11 January 2012, 11:41

Not too long ago a free software project I'm peripherally involved in decided it was time to replace its old and not broken version control system with something new and broken, and the lead maintainer conducted a straw poll of what the new system should be. My suggestion of "anything, as long as it's not distributed" was shouted down by the chorus of "anything, as long as it's distributed." Having lost the argument in that forum, I'm going to post my thoughts on why distributed version control sucks here in my own space where it's harder for me to be shouted down.

Code refactoring by combinatorial optimization

Monday 5 December 2011, 14:56

I encountered an interesting problem on the Tsukurimashou project recently, and some inquiries with friends confirmed my suspicion that if anyone has solved it, they've done it in a language-specific way for ridiculous languages. It appears I have to solve it again myself. Here are some notes.

Fixing Alpine's broken subject sort

Monday 4 April 2011, 10:09

I use the Alpine email software, which is successor to Pine. I mostly like it, but its implementation of "sort by subject" is broken and annoying.

It is documented that Alpine will strip "Re: " and variations from the start of a subject line before sorting, and that seems like something I would reasonably want: replies end up getting sorted with the things they are replies to, instead of all being grouped confusingly under "R". However, what is undocumented and unwelcome is that Alpine will also look for and remove strings enclosed in square brackets, which are typically used to identify mailing list messages. I subscribe to several mailing lists that identify themselves by square-bracketed tags at the start of the subject line while leaving the From: headers unchanged (messages are from the person who sent them instead of from the list). If subject sort worked, then as a natural consequence of how string sorting works, I could group all messages from the list together, sorted within the group by the rest of the subject. But because square-bracketed tags are silently ignored, I can't do that, and there is no way to group the mailing list messages together. There is no option to make subject sort sort on the actual subject, no really, the string that is in the Subject: header and not a munged version.

Fixed by deleting lines 4562 to 4565 of imap/c-client/mail.c in the Alpine 2.00 distribution, which check for square brackets and invoke mail_strip_subject_blob().

The Terrible Secret of OpenType Glyph Substitution

Monday 6 December 2010, 13:18

I was up until 3 this morning trying to figure out how to make OpenType glyph substitution work. That, in itself, is not news. Anyone who has tried to write substitution rules for OpenType fonts has probably gone through something similar. What is unusual, though, is that I not only succeeded, but also figured out the undocumented underlying principle so that I can predictably succeed in the future; as far as I can tell, the more usual practice is to just try things at random until one eventually either gets it working by accident, or gives up, without having learned anything useful either way.

The purpose of this entry is to provide the important information that I wasn't able to find on the Net and wish I had had. There is one important point I call the Terrible Secret, which makes all the difference to getting it to work; but rather than jump to that immediately I'm going to give the needed background first. I'll be using the terms that make sense to me, rather than the "easy" but uselessly vague simplified style used by all existing documentation I found.

Fixing the JED dealbreakers

Saturday 4 September 2010, 18:45

There are many things I like about the JED text editor, and for a number of years it has been my preferred editor for working on C code. However, it has a number of misfeatures that make it unacceptable for other tasks for which I need a text editor, so I have generally been using JED only for C code, and JOE for most other things (including, notably, English-language writing of both fiction and nonfiction in LaTeX and flat text). Just recently I had occasion to try to edit some C code on my laptop, which had a fresh default installation of JED, and it was a horrible experience, and I realized that I had, years ago, made a number of customizations to JED that I'd long since forgotten about.

For my own future reference, and anyone who might be facing a similar situation, here are some notes on changes I made. I decided while I was at it to try to not only bring the laptop's installation up to the desktop's standard so I could use it for C, but also fix as many as possible of the issues keeping me from using JED for other things on both installations, so that I could at least consider adopting it as my general editor instead of mostly using JOE. It remains to be seen whether JED will be able to serve as my all-purpose editor, but so far I've been liking it once I sorted out these issues.

In the matter of the 465 Hz tone

Friday 18 June 2010, 09:41

So, you've got an audio signal contaminated with a continuous tone at about 233 Hz, with a really strong second harmonic at 465 and some others throughout the audio spectrum. It sounds like a swarm of angry bees and makes the main signal hard to listen to. You can notch it out - that means applying a filter that simply removes the frequencies in question - but since 465 Hz is right in the important part of the speech band, the result is going to sound really bad. Any simple frequency-notch filter that blocks the interference is going to destroy things you want to keep, too. Look around the Net these past few days and you can read a lot of broadcast audio people complaining about this issue.

Time travel chaos game

Monday 5 April 2010, 13:19

Re-posting of an article first posted in May 2007.

Okay, here's a game sketch.  This idea is supposed to be a game that could live on a Web site somewhere, support a large number of players, but be fun to participate in even if you are brand new, or only connect occasionally, or if there are few or no other players.  Kind of like Wikipedia - except that my idea would actually know it's a game, unlike Wikipedia which thinks it's an encyclopedia.  I'm posting this here to make it harder for anyone to patent.

The UFP and the Filthy Humans

Friday 2 April 2010, 19:16

Re-posting of an article first posted in September 2008.

You are an officer, say a commodore, in the military-diplomatic-exploration organization of an interplanetary nation with United Federation of Planets (UFP) membership. You've been tasked with asserting your nation's interests with respect to a certain out-of-the-way planet that happens to be rich in natural resources. Unfortunately, it's already inhabited, by a race of disgusting natives we will call the Filthy Humans.