Words for similar but distinct concepts, that are not themselves similar. The ELF standard for object and executable files contains two concepts which are similar enough to confuse, but different enough that it's normally important not to confuse them, and they're called ‘section’ and ‘segment’. I often wish they'd been called by more obviously different names: ‘section’ and ‘kangaroo’, or something. And I was just reminded this morning of another similar case: ‘project manager’ and ‘product manager’ as distinct corporate roles.

If two concepts are similar but distinct, the words for them should not reflect this by also being similar but distinct! They should be as different as possible.

Moral versus probabilistic ‘expect’. This might fall into the same general category as yesterday's moral vs tactical ‘should’, though I'm not sure whether ‘probabilistic’ and ‘tactical’ are similar enough for it to count. But even if so, it's a particularly noticeable sub-case of it and worth mentioning in its own right.

Imagine a parent saying to a child, before going to visit someone for the day, ‘Now I expect you to be on your best behaviour’; and then, when the child has left the room to get ready, they turn to their co-parent and say ruefully ‘I expect him to throw a huge screaming tantrum, so we'd better be ready to leave in a hurry’. Two clearly distinct words for ‘expect’, please!

Failing to draw a distinction between any worthwhile things. There's a particular way in which a concept – a noun or adjective, or a philosophical term of art – can fail to be practically useful: by being defined in such a way that nothing, or nothing interesting, satisfies its definition. Or else nothing (interesting) doesn't satisfy its definition. As soon as you notice you're talking about a concept which encompasses either everything or nothing, you're usually wasting your time (except in the rare cases where you really intended to be talking about either everything or nothing), and should instead be looking for some alternative concept (or a less absolutist interpretation of the same concept) which manages to draw a dividing line such that at least one interesting thing falls on each side of it.

I want a word for that particular form of uselessness, so that I can much more economically point out when somebody (certainly including me) has perpetrated it, and it doesn't take me a whole paragraph just to explain why I'm giving up and trying a different approach.

Moral versus tactical ‘should’. It keeps striking me as an unfortunate property of English that the word ‘should’, and many of its synonyms and related words, are sometimes used to indicate moral obligation and sometimes used to indicate the tactically (or strategically) optimal course of action. Usually it's obvious from context which sense is meant in any given case, but not always, and I've seen just a couple too many arguments flare up from somebody misconstruing a ‘should’ as moral when it was intended tactically, or (more rarely) vice versa. It's a pain to keep tacking on disambiguating parentheses such as ‘(I'm speaking in the tactical sense here)’, so I want two clearly different words that can be used in place of the ambiguous ‘should’, at least in sensitive circumstances and perhaps more widely too.

In other news, the car hassle now seems to be mostly sorted out. I've got a new (well, second-hand, but new to me) Polo to replace my defunct Clio; my insurance company have paid me a settlement that looked relatively plausible in terms of my own perusal of online price guides; I've given back the temporary hire car; all that's left now is for the insurers to sort out getting paid back by the other insurers, for which they don't need my help as far as I know. Phew.

Though I've been musing in the past few days that my methodology for choosing a car is wrong. (If you think it seems foolish to think about this just after I buy one, I wouldn't disagree, but better that than not thinking about it at all!) In the past my approach has been to think up a list of models that meet my basic requirements for size and price range and suchlike, then go and test-drive all of them; on some of the test drives I get a strong sense of wrongness, when it just doesn't behave the way I instinctively feel a car should, and then I go ‘warrgh!’ and decide not to buy that one.

The thing is, I got that same sense of wrongness the first time I got into the hire car, and actually it turned out I adjusted to that fine over a fortnight or so, to the point where the Polo now feels less right to me than it did in the test drive. I'm sure I'll readjust fine to the Polo, of course, but that's precisely my point: if that feeling of culture shock at an unfamiliar car is a basically transient issue, I shouldn't be basing buying decisions on it. What I want to be able to do is to distinguish the annoyances which are merely unfamiliarity from the ones that are genuinely annoying and will still be irritating me after a month, and I'm not sure if I can do that on a short test drive.

Or perhaps I should assume that any immediate annoyance is something I'll get used to eventually, and make my buying decisions solely on objectively measurable properties such as that model's statistical reliability, fuel consumption, likely TCO, and tedious things like that.

In the past few weeks, mostly due to sorting out my car hassle, I've had to do a few things (e.g. making a particular phone call) which I knew in advance would be stressful.

I've noticed during the process that there's a certain length of time beyond which I don't seem to worry much about the stress of doing the thing. It's fairly reliably seemed to be about two days: if I plan to do such a thing well in advance, I don't feel stressed about it until about two days before it, and then I start to worry, and to curse my former self for having committed me to doing it. Whereas if I plan to do it within two days, I'm much more prone to let the visceral dislike of the idea affect my decision to do it at all.

Of course this is all perfectly normal human nature and in either case my clear duty is to ignore the feeling of stress and just get on and do it anyway. But it's been striking me as interesting that the time horizon seems so consistent. It's as if the ‘me’ more than two days in the future is someone I don't quite see as myself, and hence I can foist unpleasant jobs on him with relative equanimity; but the nearer-future me is really me, so that jobs I foist on him are ones I know I'm going to have to do…

In the past two days I have made more phone calls than I typically make in three months. I've been sorting out buying a car, and trying to get it independently inspected before I do so; for various reasons involving last-minute schedule changes and people not having vital bits of information so that I have to call someone else to get them and call back to pass them on, this has involved an absolutely frantic couple of days of telephoning all sorts of people repeatedly. I expect everyone involved is sick of the sound of my voice by now – I certainly am – and since this is an open-plan office I also expect my colleagues have concluded that I haven't done anything this week but call up car-related people on the phone and get cross with them.

It wouldn't have been so bad if every call I needed to make had gone right the first time. Instead, nearly every attempted call I've made today or yesterday has involved being unable to get through to the person I want, calling back later and/or being promised a callback, and usually taking about three or four calls to get anywhere. This has tended to make me feel as if every time I pick the phone up I'm engaging in a battle of wills rather than (as I should be) simply requesting or providing information, and it's now got to the point where I feel a strong sense of something I can only describe as ‘telephone fatigue’ every time I realise I'm going to have to pick the thing up again.

Bonus points on the battle-of-wills score go to the RAC vehicle inspections line, which when all the lines are busy does not place your call in a queue but instead automatically puts it through to a support division who can't actually do anything to help you except promise a callback that may or may not materialise. Another bonus point goes to the person I tried to phone twice, was promised a callback by a receptionist both times, he finally did call back just when I'd left my desk alone for two minutes and I got back to the phone just as it went to voicemail, and then I immediately called him back and he promptly put me on hold.

If I never so much as look at another telephone for the rest of my life, it'll be half an hour too soon. I'd quite like to put a tea cosy over mine for the rest of the week, so it doesn't loom in the corner of my vision and annoy me merely by existing.

Direct Line rang me up yesterday, told me my car was a write-off, and let me know what paperwork would have to go where as a result.

Today I rang them back to ask them the one question I hadn't remembered to ask at the time, which is how long I get to keep the hire car they supplied me with. The woman I just spoke to had managed (or, more likely, her computer system had managed) to lose all my details, but said that the usual procedure is that I have to give the hire car back five days after receiving the settlement cheque.

That doesn't seem very long! I had guessed they'd at least let me keep it for a few weeks while I sorted out finding and buying a new car. I can of course start that process in advance of receiving the cheque – but I could easily imagine that not everybody would have the spare money to do that. So I'm less impressed with DL this week than I was last week.

On the plus side, my neck is definitely getting better. Can't credit DL with that one, though!

When I bought a house a few years back, I was initially very scared of all the complicated and and arcane procedure that I'd heard was involved, and I wondered in particular how I (or anyone else without experience) could possibly get through it without getting something wrong. I found out (of course) that the answer is your solicitor: in addition to their nominal role of handling the legal aspects of property transfer, they also perform the vital secondary role of experienced guide: the person who understands the whole procedure, tells you what you need to do when, lets you know when you have to make decisions and expresses them in terms that make sense, and makes sure nothing gets left out.

After my car accident last week, I had a similar feeling of ‘help, this is surely all too complicated for me’, and was relieved to find out that in such situations your own insurance company performs a similar secondary role, even when they're confident it's going to be the other lot paying. At least, mine is doing that, and doing it very efficiently; rumour has it that some insurers will basically let you fend for yourself in the post-accident clearup process. So I'm currently in a good mood with Direct Line.

So DL arranged for a temporary hire car to be delivered to my office on Friday, and someone from a body shop showed up early this morning to pick up my own car for repair. (The chap who came out said it probably shouldn't take too long, but then actually looked at the dent and muttered ‘bloody hell’. So I'm not sure whether he stands by that estimate any more, but apparently they'll ring me at some point and let me know what the situation is.)

My neck is still a bit stiff, but the doctor reckoned it was nothing serious, and it's definitely feeling better than it was last week.

I had a car accident on the way home from work this evening. Pulled up at a roundabout and the car behind me didn't stop. Bang, rear-end shunt.

Fortunately a Highways Agency vehicle happened to pass by a minute or two later, and took charge smoothly. The other driver and I were both totally calm, but also totally dithering because we didn't really know what to do next. We knew we had to exchange details, but neither of us was quite sure what else if anything had to be done.

I think I'm personally OK, though I'll go to a doctor tomorrow to make sure. I'm less convinced that my car will recover…

Years ago, when I used to juggle a lot, I'd always notice that when I spent a whole evening juggling for the first time in a while (e.g. coming back to university at the start of term and attending the first meeting of the juggling society), my legs would hurt the next morning from all the crouching down to pick up dropped things.

I had completely forgotten this phenomenon, but I belatedly remembered it this morning, after james_r brought a bag of juggling kit to sonicdrift and mobbsy's party yesterday. I'm glad I'm down for spending most of today sitting in front of a computer!

Still, it was fun to dust off some old skills, although I had a little of the same problem as I had last year playing the violin at aiwendel's do. (Gosh, apparently that party was a year before this one to the day. 11th July is clearly my personal Resurrect An Old Skill Day.) I could remember what I used to be able to do, and although I gave a reasonable account of myself, I knew I was distressingly out of practice. Come to think of it, I had much the same problem as with the violin: the tricks I wanted to do were things I no longer had the skill for, but I improved later in the evening as I toned down my own expectations and moved over to doing simpler stuff that I could still manage.

It was also fun to see some novice jugglers having a go later on and to give them (hopefully) helpful advice. That was another thing we used to do all the time at the university juggling society, but I'd forgotten just how satisfying it could be to see somebody's skill visibly improve in a period of hours.

(I also got comically clonked on the head by an incoming club while attempting to pass with James, but I think that must have looked more painful than it actually was. I've had worse things happen to me recently!)

Bah. Twice in the past week I've been bitten by pieces of badly thought out syntax which look general but aren't. (Curiously, both have involved braces.)

In bash 3, the brace expansion syntax has been extended to permit numeric ranges separated by ‘..’, so that where you could previously have written ‘a{0,1,2}’ and had it expand to ‘a0 a1 a2’, you can now achieve the same thing by writing ‘a{0..2}’. However:

$ echo a{0..9}
a0 a1 a2 a3 a4 a5 a6 a7 a8 a9
$ echo a{A,B,C,D,E,F}
aA aB aC aD aE aF
$ echo a{0..9,A,B,C,D,E,F}
a0..9 aA aB aC aD aE aF

Bah! You can only get the two types of braced thing to combine by using a second pair of braces inside the first, which don't look as if they ought to be necessary, but they are:

$ echo a{{0..9},A,B,C,D,E,F}
a0 a1 a2 a3 a4 a5 a6 a7 a8 a9 aA aB aC aD aE aF

That was last week. Today's is in gnuplot, which lets you write a braced pair of numeric literals and interprets them as the real and imaginary parts of a complex number. This is easy to find out even without looking in the manual, because it uses the same syntax on output if you do something that has a complex result:

gnuplot> print {1,1}*{2,3}
{-1.0, 5.0}
gnuplot> print sqrt(-1)
{0.0, 1.0}

But what you might not have expected, having discovered that, is that it only applies to numeric literals. You can't, for instance, do this:

gnuplot> print {pi/2, 1.234}
               ^
         invalid complex constant

That would be too easy, of course. Instead you must do something much more ugly, like this:

gnuplot> print pi/2 + {0, 1.234}
{1.5707963267949, 1.234}

And if you wanted a non-constant imaginary component too, I can only assume you'd be forced to fall back to writing the expression for the imaginary part, multiplying explicitly by {0,1}, and adding it to the expression for the real part. Bah!

I just found a USB key in the pocket of my jeans. The jeans came out of the drawer yesterday, and I haven't seen the key in months. Ergo, it's gone through the laundry at least once. Oops.

It still seems to work, though, and it hadn't even lost the last lot of data I remember putting on it!

Attempting a task, and then realising simultaneously that (a) it was a bad idea and would have had a bad consequence, but also (b) I mucked it up in such a way that the bad consequence did not in fact occur.

I can never work out what I should be calling myself an idiot for, in that situation!

I've been noticing this week that I appear not to be the sole occupier of my property any more.

Last weekend I heard loud meowling noises around the time I was going to bed, close enough to make me wonder if they were coming from my own garden rather than a neighbour's. And, sure enough, every time I've gone out of the back door this week to put something in the wheely-bin, a black cat with white feet has been in my back garden. This morning I saw it out of the back window, walking along the fence right next to me and looking at me coolly.

It hasn't let me come near it; every time I get within the same half of the garden, it looks startled and hops it over the fence.

I'm getting the impression that it (no idea whether it's a he or a she) has claimed my garden as part of its territory, there being no resident quadruped to challenge the claim. (The previous owners of this house had a big dog, but that was in 2007; now I think about it, it faintly surprises me that the local feline community has taken this long to notice the dog's absence and reallocate the space. Perhaps it just takes a long time for the City Kitty Committee to organise a meeting.)

I don't think I actually object to it; there's nothing in my garden I particularly value except the sheds, which I reckon are safe enough. If it wants to damage any of the plants, it's most welcome to: 90% of them are weeds, even after I've weeded.

But if it's going to be there, I feel as if I'd like to know its name, and at least be able to say hi to it in passing without it going ‘warrgh, scary biped’ and levitating out of range.

A thing that has struck me from time to time is the surprising number of things that come in varieties labelled as ‘1’ and ‘3’, or ‘1st’ and ‘3rd’, missing out 2.

I tend to think of this as ‘Trinity Boat Club Syndrome’, since my standard example case is the 1st and 3rd Trinity Boat Club. (I've always faintly wondered what happened to the 2nd, and had rather hoped it would have been disbanded in mysterious circumstances after the inadequately explained sinking of a John's boat, or possibly an Oxford one; I was recently disappointed to find out that their website actually answers the question and it's nothing so exciting.)

There are several other common ones. You hear a lot about the Third World and the First World, but ‘Second World’ is not a widely used phrase by comparison. Fiction tends to appear in single novels or trilogies, with relatively few two-volume works in between. And both books and computer games are often described as first-person or third-person, but very few of either are second-person.

More domain-specific examples include the fact that in technical drawing, orthographic projections come in first angle and third angle, but never second, and that in violin-playing it's common to use first position and third position, but second position (while a perfectly meaningful concept) comes up rather less often.

So: what other examples of this haven't I thought of, and what can we do to rehabilitate the poor left-out number 2?

I cannot choose the wine in front of me.
And yet I can't discount a bluffing play:
The wine in front of you it cannot be.

You think I'm stalling, but you must agree
That while I hope your choice you might betray,
I cannot choose the wine in front of me.

You beat my Turk, a fighting prodigy,
So you might trust your strength to save the day.
The wine in front of you it cannot be.

You beat my Spaniard very skilfully.
So you would put the poison far away:
I cannot choose the wine in front of me.

I know the poison comes from oversea.
Its origin enables me to say
The wine in front of you it cannot be.

I switched the glasses when you couldn't see!
Yet, unresolved, the paradox must stay –
I cannot choose the wine in front of me;
The wine in front of you it cannot be.

(With apologies to William Goldman. It randomly occurred to me in the bath that this particular poetic form and piece of dialogue were a strikingly good fit for each other.)

Last night I walked over to cartesiandaemon's place at around 9pm, for a small gathering of people.

On the way there I approached a group of five rowdy-looking lads heading the other way along the pavement, who were roaring ‘wooorrr’ at each other. As I passed them, they suddenly went quiet, and as I walked away I heard one of them mutter behind me ‘Thought that was a PCSO for a moment’.

I certainly wasn't deliberately imitating a PCSO, or any other kind of official person. I was just walking along the street, wearing black jeans and a black T-shirt. Though I suppose, in retrospect, I did have straps visible on my torso, a complicated device hanging off my belt, was walking with a long and confident stride and jingling faintly as I went, so some or all of those might have contributed to such an impression. (The straps were attached to a rucksack containing a jumper and a bottle of wine, the device on my belt is a digital watch, the jingle was keys and spare change, and the gait signified a desire to get there quickly rather than a sense of authority and power, but I suppose they weren't to know any of that.)

So on the one hand it amused me at the time that I singlehandedly put the wind up five rowdies by accident. On the other hand, I did actually just go and look up the wording of the law on the web, to make sure it wasn't possible to accidentally commit illegal police impersonation!

(I don't think so, though. As I read the Police Act 1996 section 90, you have to either be deliberately trying to deceive, or have something that's distinctively police uniform or a badge or document.)

The sentiment ‘it's not much to ask’, presented as the sole justification of why people should do something you want. When everybody has a ‘not much to ask’ request and they're all different (or, occasionally, when the same person thinks of a different one every week for a year), they add up until collectively they are a lot to ask – so some of them have to go unfulfilled, despite each of them individually being so small that the asker couldn't imagine how anyone might have a good reason not to do it.

Don't just point out that the cost is low and leave it at that. Show why the benefit (whether to you, to whoever you're asking for it, or to somebody else) outweighs it!

Sometimes, in previous years, I've googled around to try to find interesting things about the third of May. For instance, the other year I discovered that I shared a birthday with Machiavelli. (Previously the only person I'd known of who shared my birthday was Jeff Sinclair, who is two hundred and forty-one years younger than me :-)

This year, I didn't need to go looking, because one came to me. Randomly skimming my LJ friends-friends page some months ago, I came across a snippet in Neil Gaiman's blog, who had in turn found it in a book of legends from the Inner Hebrides:

…the third of May, when the Devil and his angels were cast out of heaven (and therefore 3rd May is a day on which no important undertaking should be begun and on which it is unpardonable to commit a crime)…

That is, I would have to say, considerably more awesome than Machiavelli. Sorry, Nick, but there it is.

Working on a compiler tool chain has some odd side effects. On my work computer:

$ cd ~/src/misc
$ ls hello* | wc -l
60

It's only just occurred to me to think of it this way, but I appear to be a power user of hello-world programs.