On Tue, Jul 19, 2011 at 12:28:46PM -0600, Idris Samawi Hamid ادريس سماوي حامد wrote: > On Tue, 19 Jul 2011 12:06:00 -0600, Khaled Hosny > <[email protected]> wrote: > > >>>The algorithm actually has a dedicated rule of this use case: > >>> http://www.unicode.org/reports/tr9/#Higher-Level_Protocols > >> > >>Sure. At the same time, these are exactly the kinds of rules we > >>_don't_ want to deify. > > >I'm not deifying anything, but it is unfair to criticise the algorithm > >for not considering certain use cases while it is actually considering > >them! > > >>The people who write these things are not typographers. The bidi > >>algorithm mixes text-editing needs with typesetting needs. > > >I haven't seen any evidence of this, no I see how this would be a bad > >thing. Unicode BiDi algorithm have been implemented and deployed by > >millions of users world wide, and its behaviour is what most people > >expect, drifting from it too much is not a wise idea IMO and I can see > >it making more problems than it solves. > > =================== > A higher-level protocol may use an entirely different algorithm that > heuristically auto-detects the paragraph embedding level based on > the paragraph text and its context. For example, it could base it on > whether there are more RTL characters in the text than LTR. As > another example, when the paragraph contains no strong characters, > its direction could be determined by the levels of the paragraphs > before and after. > =================== > > Vague, speculative, and whoever wrote that clearly is not a > typographer but someone apparently interested in text-editors. For > someone writing, eg, a multilingual critical edition this would > create havoc.
Those are mere hints; examples on what a higher protocol would do, not part of the standard and you are in no way obliged to implement them. > Anyway, the only point was that these rules need not be hard-coded > in the core of luatex, that's all. Agreed, though one can still write a core implementation that is configurable, still, I don't see much benefit here over a pure lua implementation. Regards, Khaled -- Khaled Hosny Egyptian Arab
