NNBSP

[Richard Wordingham via Unicode]

On Thu, 17 Jan 2019 04:51:57 +0100
Marcel Schneider via Unicode <unicode at unicode.org> wrote:

> Also, at least one French typographer was extremely upset
> about Unicode not gathering feedback from typographers.
> That blame is partly wrong since at least one typographer
> was and still is present in WG2, and even if not being a
> Frenchman (but knowing French), as an Anglophone he might
> have been aware of the most outstanding use case of NNBSP
> with English (both British and American) quotation marks
> when a nested quotation starts or ends a quotation, where
> _‘ ”_ or _“ ’_ and _’ ”_ or _” ’_ are preferred over the
> unspaced compounds (_‘”_ or _“’_ and _’”_ or _”’_), at
> least with proportional fonts.

There's an alternative view that these rules should be captured by the
font and avoid the need for a spacing character.  There is an example
in the OpenType documentation of the GPOS table where punctuation
characters are moved rightwards for French.

This alternative conception hits the problem that mass market Microsoft
products don't select font behaviour by language, unlike LibreOffice
and Firefox.  (The downside is that automatic font selection may then
favour a font that declares support for the language, which gets silly
when most fonts only support that language and don't declare support.)

Another spacing mess occurs with the Thai repetition mark U+0E46 THAI
CHARACTER MAIYAMOK, which is supposed to be separated from the
duplicated word by a space.  I'm not sure whether this space should
expand for justification any more often than inter-letter spacing. Some
fonts have taken to including the preceding space in the character's
glyph, which messes up interoperability.  An explicit space looks ugly
when the font includes the space in the repetition mark, and the lack of
an explicit space looks illiterate when the font excludes the leading
space.

Richard.