- From: Aharon (Vladimir) Lanin <aharon@google.com>
- Date: Sun, 26 Sep 2010 17:43:37 +0200
- To: fantasai <fantasai.lists@inkedblade.net>
- Cc: public-i18n-bidi@w3.org, W3C style mailing list <www-style@w3.org>
- Message-ID: <AANLkTinrG3Zzfb1M4NQWtqMkq2nabzc-CgxwV0Jzm3pL@mail.gmail.com>
> The spec says > > # User agents that support bidirectional text must apply the Unicode > # bidirectional algorithm to every sequence of inline boxes > # uninterrupted by a forced (bidi class B) line break or block boundary. > # This sequence forms the "paragraph" unit in the bidirectional algorithm. > > In what way is this not sufficient to address your concerns? Taken by itself, it is perfectly explicit and sufficient. The problem is that the unicode-bidi:isolate spec is also perfectly explicit and sufficient, and, it seems to me, conflicts with the above: for the purpose of bidi resolution in its containing paragraph (if any), the [unicode-bidi:isolate] element itself is treated as if it were an Object Replacement Character (U+FFFC). When both specs apply, I think it should be either implicitly obvious or explicitly stated which one wins. I do not think it is implicitly obvious, so I would like to state it explicitly. Once we are at it, it is nice to mention the other cases where unicode-bidi:isolate has no effect, like the first two you mention, although this fact is implicitly obvious from the specs, just for the convenience of the reader (not as a normative definition), but I would not have brought those cases up if it were not for (what I think are) the ambiguous ones. Aharon On Sun, Sep 26, 2010 at 4:26 PM, fantasai <fantasai.lists@inkedblade.net>wrote: > On 09/25/2010 05:25 PM, Aharon (Vladimir) Lanin wrote: > >> The current definition >> <http://dev.w3.org/csswg/css3-text-layout/#unicode-bidi> >> >> of unicode-bidi:isolate states: >> >> "For the purposes of the Unicode bidirectional algorithm, the contents >> of the element are considered to be inside a separate, independent >> paragraph, and for the purpose of bidi resolution in its containing >> paragraph (if any), the element itself is treated as if it were an >> Object Replacement Character (U+FFFC). (If the element is broken across >> multiple lines, then each box of the element is treated as an Object >> Replacement Character.)" >> >> I think that it is worthwhile to stipulate that unicode-bidi:isolate has >> no effect whatsoever on any element that either creates a separate UBA >> paragraph, or serves as a UBA paragraph break in its containing UBA >> paragraph. Such elements include: any element taken "out of flow" e.g. >> with float or position:absolute, any element with display other than >> "inline", <br bidibreak=hard>, <textarea>, <input type="text">. This >> > > Elements that are out-of-flow do not affect their surrounding contents. > That is the definition of out-of-flow, and it needs no further > clarification here. As for atomic inlines such as <textarea> and > <input>, they are handled as U+FFFC under the non-textual entities > clause (which will be further clarified in the next revision of CSS2.1) > and the bidi independence of their contents are covered by the spec text > quoted below. > > stipulation is particularly important for the display:block and <br >> bidibreak=hard> elements, for whom unicode-bidi:isolate's specification >> that the element be treated in the containing paragraph as if it were >> U+FFFC, i.e. bidi class ON, conflicts with the proposed specification >> < >> https://docs0.google.com/a/google.com/document/edit?id=1zR06HjhVvt7ySAJeqq7zQZSzpLTRgV8AoQNo_vNznX4&pli=1&authkey=CIXomoYI# >> > >> >> that these element be treated in the containing paragraph as if they >> were bidi class B. >> > > The spec says > > # User agents that support bidirectional text must apply the Unicode > # bidirectional algorithm to every sequence of inline boxes > # uninterrupted by a forced (bidi class B) line break or block boundary. > # This sequence forms the "paragraph" unit in the bidirectional algorithm. > > In what way is this not sufficient to address your concerns? > > ~fantasai >
Received on Sunday, 26 September 2010 15:44:55 UTC