Antoine Leca scripsit:
I am sorry John, I should have miss a post of yours. I asked you where it is
written, and did not find any answer to this; unless someone consider that
all marks, including spacing combining vowels, are "(European) diacritics".
Well, it depends on what the equivoque "combining marks" in the title of Section 7.7 means. This is where (p. 187) the remarks about SP and NBSP appear:
# Marks as Spacing Characters. By convention, combining marks may be exhibited
# in (apparent) isolation by applying them to U+0020 SPACE or to U+00A0 NO-BREAK
# SPACE. This approach might be taken, for example, when referring to the
# diacritical mark itself as a mark, rather than using it in its normal way
# in text. The use of U+0020 SPACE versus U+00A0 NO-BREAK SPACE affects line
# breaking behavior.
These words are equivocal in more ways than one. What does "By convention... may be exhibited" mean? Does this mean that the sequence <SPACE, mark> should be rendered as an isolated mark, or does it mean that optionally it may be? Is the convention one which is optional for those encoding texts, or optional for implementers? Are these words intended to be in any way prescriptive, or are they intended merely to be descriptive of what some people have chosen to do? If "This approach might be taken, for example, when referring to the diacritical mark itself as a mark", what other approach might be taken as an alternative? The language is altogether far too loose for a standard. The result is the current confusion, according to which people are trying to encode texts according to what they think Unicode expects them to do, and finding that the rendering engines they use do not provide either this or any other way to display what they want to display, and yet claim to conform to Unicode.
-- Peter Kirk [EMAIL PROTECTED] (personal) [EMAIL PROTECTED] (work) http://www.qaya.org/
