[css3-text] one dot leader (U+2024), vertical presentation form for vertical horizontal ellipsis (U+FE19)

UAX14 data [1] marks the following as belonging to the IN (inseparable)
line breaking class:

   - U+2024 (one dot leader)
   - U+2025 (two dot leader)
   - U+2026 (ellipsis)
   - U+FE19 (presentation form for vertical horizontal ellipsis)

In contrast, CSS3 Text only specifies line break behavior for U+2025 and
U+2026 [2].

Note that the UAX14 [3] behavior for all of these characters is to forbid
breaking between any pair of these characters, i.e., they are considered as
XP (exclude pair) characters. However, CSS3 Text does not specify that
UAX14 semantics apply in any case with respect to the IN breaking class;
i.e., the default line breaking rules in Section 5.1 [4].

So, what should the behavior be for U+2024 and U+FE19? My reading of the
current text is that this behavior is unspecified, i.e., these may be
considered as soft break opportunities, but this is left UA dependent. Is
that the intended reading?

[1] http://www.unicode.org/Public/UNIDATA/LineBreak.txt
[2] http://dev.w3.org/csswg/css3-text/#line-break
[3] http://unicode.org/reports/tr14/#DescriptionOfProperties
[4] http://dev.w3.org/csswg/css3-text/#line-break-details

Received on Thursday, 30 August 2012 02:54:10 UTC