[CSS3 Text] Japanese Iteration Marks

CSS3 Text introduces a property to control whether strict or loose
line breaking rules are used in Japanese:

   http://www.w3.org/TR/css3-text/#word-break

One of the differences between strict and loose is allowing breaks before
Japanese iteration marks. I have read in various sources that when there's
a break before an iteration mark, the iteration mark should be replaced
with the appropriate character. Wikipedia describes and illustrates this
behavior here:

   http://en.wikipedia.org/wiki/Iteration_mark
   http://en.wikipedia.org/wiki/Reference_mark#Repetition_marks

I am currently speccing this in CSS3 Text. What I have so far is

    | If the UA breaks before a Japanese iteration mark, it should* replace
    | the iteration mark the character represented by the iteration mark:
    |
    |   * the corresponding Han character, for IDEOGRAPHIC ITERATION
    |     MARK (U+3005) and VERTICAL IDEOGRAPHIC ITERATION MARK (U+303B)
    |   * the (appropriately-voiced) corresponding Hiragana character,
    |     for HIRAGANA ITERATION MARK (U+309D) and HIRAGANA VOICED ITERATION
    |     MARK (U+309E)
    |   * the (appropriately-voiced) corresponding Katakana character,
    |     for KATAKANA ITERATION MARK (U+30FD) and KATAKANA VOICED ITERATION
    |     MARK (U+30FE)
    |
    | A sequence of <var>N</var> iteration marks corresponds to the sequence
    | of <var>N</var> characters that immediately precedes it. If an iteration
    | mark does not correspond to a character of the matching script type,
    | then the iteration mark must not be replaced.

This text doesn't address the vertical iteration marks U+3031-3035, however.
I'm not sure exactly how those work. Can anyone explain what behavior is
expected?

* I am currently using 'should' rather than 'must'. Let me know if I should
   change that (or anything else).

~fantasai

Received on Wednesday, 10 January 2007 07:05:23 UTC