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

On Thu, Aug 30, 2012 at 2:40 PM, Koji Ishii <kojiishi@gluesoft.co.jp> wrote:

> > 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?
>
> Yes. As discussed before, CSS Text Level 3 recommends differences between
> line-break values. We made this list by hearing typographic experts in CJK,
> and also by referring existing products. U+2025 and U+2026 were in the list
> to behave differently between normal/strict and loose, but U+2024 and
> U+FE19 were not.
>
> So UA may change their behavior/class between normal/strict and loose, or
> keep consistent across values.
>

OK. It may be worth adding a note saying that 2024 and FE19 are
intentionally not included; otherwise, other readers will ask the same
question.


> -----Original Message-----
> From: Glenn Adams [mailto:glenn@skynav.com]
> Sent: Thursday, August 30, 2012 11:53 AM
> To: W3C Style
> Subject: [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
>
>