Martin Duerst wrote: > At 07:26 05/11/23, Gregg Reynolds wrote: > >>1. It was legacy, so Unicode had so support it. Then they went > berserk with it. >>2. Whoever made that first fateful design mistake either didn't > understand what he was doing, or else designing in the service of the > Arabic/Hebrew/etc speaking community was not a priority (making Western > software work for those languages cheaply was most likely the > motivation, hence the desire to avoid handling LSD-first digits. But > that's just my speculation.) > > Well, Unicode is of course about encoding all scripts of the > world, whatever the direction. It seems extremely obvious that > in that context, you'd try to come up, or adopt, a solution > that didn't only allow each script to work on it's own, but > also different scripts together. The final algorithm is > probably more complex than it really needed to be, but that's > similar for most standards. Calling it 'berserk' doesn't help > in my view. > > Regarding LSD (least significant digit) first, that's of course > the crucial point. If you say that making Western software > work for RTL languages cheaply was the motivation for the > bidi algorithm, and for making RTL languages inherently bidi,
No, I was speculating that that might have had something to do with modeling RTL digit strings as MSD-first. Without that, you have problems with math routines. If we were starting from scratch today that might not be a big problem, but in the 50s and 60s processor time was hugely expensive, and most (business) computing was bean-counting. There were probably good economic reasons at the time in favor of the MSD-first design. But that's idle speculation. > then you seem to say that implementing LSD first is even more > difficult/expensive than implementing bidi. I'd probably have Not at all; only with respect to functions etc. that interpret digit strings as numbers. > to agree with that: While the technical details of a single > LSD-first number are much easier, making sure that everybody > in the world always knows which numbers are MSD-first and > which numbers are LSD-first would be a very expensive nightmare. > Messing up things like 123 and 321 can easily get expensive. > Having text, rather than numbers, run the wrong way at times, > doesn't look better, but is much better re. error detection. Similar arguments were made on the Unicode list not too long ago. Let's please not open up that debate here ;), but for what it's worth I never understood what the worry is. Personally I don't see any possibility of confusion, but others clearly do. -gregg _______________________________________________ emacs-bidi mailing list [email protected] http://lists.gnu.org/mailman/listinfo/emacs-bidi
