wil writes: | John, you need to loosen your Goedel... Heh. Actually, if you think about it, Goedel's Theorem doesn't actually apply to music notation, staff or abc. The reason is that his theorem was only proved for languages of at least a certain "minimal" expressive power, and the minimum was the ability to count. He proved that a language that can count is either incomplete (i.e., some syntactically-valid statements have no meaning) or inconsistent (some valid statements have two meanings).
It's strange but true that music notations don't actually need (or have) the ability to count. So they are below Goedel's minimum expressive power, and could well be both complete and consistent. I wonder if lilypond or MusicML can count? Humans can (usually) count, so Goedel's Theorem applies to them. I saw a cute example of this a few years ago, in the form called Whitely's Paradox. In our case, we present the statement: Wil Macaulay cannot consistently assert this statement. We ask Wil whether this sentence is true, and no matter whether he answers "Yes" or "No", we observe that he is contradicting himself. We might also ask whether musicians are below Goedel's minimum in expressive power, since they routinely use a written language that lacks the ability to count, and don't seem to notice a limitation. So it's possible that Whitely's Paradox may not apply to musicians. | By the way, Skink handles the alternate bar stuff you posted, but I | have no idea what it "should" look like. What would you have | expected? The two alternate bars in question should look pretty much like two alternate endings, but they aren't endings and so lack the usual colons that indicate going back to the start. For an example of what it might look like, try: http://jc.tzo.net:1742/~jc/cgi/abc/TuneList/~jc/music/abc/src/jcabc2ps/abc/ (This is on my home machine, where I've been experimenting with some other useful extensions.) Scroll down to the SweetMaidOfGlendaruel entry and ask for PS or EPS or some other graphical form of the tune. You see this sort of thing a lot in bagpipe music. I was duly impressed the first time I noticed that abc2ps handled it without complaint. Of course, it also supports the K:Hp and K:HP gimmicks for the two common forms of Highland Pipe notation, so it's not that much of a surprise that other bagpipey things are supported. The idea here is that repeats and alternative bars are different concepts that need not be confused. It's true that to use alternatives, you do need to repeat, else alternatives are pointless. But in some music, a repeated phrase may vary not only in the endings, but in other measures as well. It's a curiosity of much Western music that variations in repeats happen mostly at the very ends of the phrases. This isn't true of some kinds of music. One kind is traditional Scottish bagpipe music (which could well be called "non-Western" ;-). The people who play this music do use the ordinary notation for alternative bars in places other than the ends of parts. We've had a few brief discussions of this in the past. I did notice some time back that abc2ps in fact had no problem with this. It uses the |: and :| symbols to indicate repeats, and uses [1 and |1 to indicate something to be played the first time only, etc. The implementations of these are in fact not related, and they don't interact. So you can use the notation for alternate measures anywhere you like. The only question is how it determines the end of the alternates. For [1 this is easy; it ends at [2. For [2, it uses the kludge of counting measures, and it only works if the alternates have the same number of measures. (This could be fixed quite easily, but that's a different topic.) It draws the final vertical line above the staff if it sees a double bar, and that's why I used a double bar in my first example. To subscribe/unsubscribe, point your browser to: http://www.tullochgorm.com/lists.html
