> Date: Sun, 20 Apr 2014 12:58:23 -0700 > From: Asmus Freytag <[email protected]> > > On 4/20/2014 3:24 AM, Eli Zaretskii wrote: > > Would someone please help understand the following subtleties and > > obscure language in the UBA document found at > > http://www.unicode.org/reports/tr9/? Thanks in advance. > > Eli, > > I've tried to give you some explanations
Thanks! > in some places, I concur with you that the wording could be improved > and that such improved wording should be proposed to the UTC (or its > editorial committee) for incorporation into a future update. How do we do that? > For details, see below. > > > > 1. In paragraph 3.1.2, near its very end, we have this sentence (with > > my emphasis): > > > > As rule X10 will specify, an isolating run sequence is the unit to > > which the rules following it are applied, and the last character of > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > > one level run in the sequence is considered to be immediately > > followed by the first character of the next level run in the > > sequence during this phase of the algorithm. > > > > What does it mean here by "the rules following it"? Following what? > > That looks like a bad referent, but from context, this "it" must be X10 Ah, so simply saying "the following rules" or "rules following X10" would be enough. > Bullet 1 could be changed to > > . Create a stack for elements each consisting of a*code point* > (Bidi_Paired_Bracket property value) > and a text position. Initialize it to empty. > > to make things more clear. And a slight wording change might help the > reader with item 2: > > 2. Compare the*code point for the*closing paired bracket being > inspected or its > canonical equivalent to the*code poin*t (Bidi_Paired_Bracket > property value) in the current stack > element. > > > And, to continue > > 3. If the values match, meaning*the character being inspected and the > character** > ** at the text position in the stack* form a bracket pair, then [...] Right, this makes the description a whole lot more clear. > Apply rules W1–W7, N0–N2, and I1–I2 to each of the isolating run > sequences. > For each sequence, [completely] apply each rule in the order in which > they appear below. > The order that one isolating run sequence is treated relative to another > does not matter. > > I believe the above restatement expresses the same thing in fewer words. It does, thanks. > > 5. Rule N0 says: > > > > . For each bracket-pair element in the list of pairs of text positions > > > > a. Inspect the bidirectional types of the characters enclosed > > within the bracket pair. > > b. If any strong type (either L or R) matching the embedding > > direction is found, set the type for both brackets in the pair > > to match the embedding direction. > > > > First, what is meant here by "strong type [...] matching the embedding > > direction"? Does the "match" here consider only the odd/even value of > > the current embedding level vs R/L type, in the sense that odd levels > > "match" R and even levels "match" L? Or does this mean some other > > kind of matching? Table 3, which the only place that seems to refer > > to the issue, is not entirely clear, either: > > > > e The text ordering type (L or R) that matches the embedding level > > direction (even or odd). > > > > Again, the sense of the "match" here is not clear. > > even/odd --- R/L match, might be made more explicit I agree this should be made more explicit, as this is a somewhat subtle issue that might trip the reader. > > Next, what is meant here by "the characters enclosed within the > > bracket pair"? If the bracket pair encloses another bracket pair, > > which is inner to it, do the characters inside the inner pair count > > for the purposes of resolving the level of the outer pair? > They do, so there's no need to change the text. It might be a good idea to say that explicitly, e.g. as a note, or at least provide another example where the strong characters are only inside an inner bracket pair, which will send the same message to the reader. Thanks again for the clarifications. _______________________________________________ Unicode mailing list [email protected] http://unicode.org/mailman/listinfo/unicode
