Bidi: inserting Japanese paragraphs in Arabic/Farsi document

[Eli Zaretskii]

> From: Philippe Verdy <verdy_p at wanadoo.fr>
> Date: Sun, 20 Nov 2016 17:20:49 +0100
> Cc: Simon Cozens <simon at simon-cozens.org>, 
> 	unicode Unicode Discussion <unicode at unicode.org>
> 
> The alignment of the paragraph to the right is optional, it is less essential.

It's essential for people who speak those languages.  Not seeing the
alignment would cause some brows to be raised (and can also cause
incorrect reading in some marginal cases).

> That alignment is prefered only when it is a separate paragraph, but if the Japanese citation is within an Arabic
> paragraph encoded as :
> 
> ARABIC-ONE "【Japanese1】Japanese2" ARABIC-TWO
> 
> I expect to see
> 
> OWT-CIBARA Japanese2 【Japanese1】"" ENO-CIBARA
> 
> aligned to the right margin

No, you should see this:

 OWT-CIBARA "Japanese2 【Japanese1】" ENO-CIBARA

That's what Emacs shows me.

> There's still the problem of surrounding quation marks that don't form matching pairs (unlike brackets), that's
> why authors will likely use mirrorable quotation marks, or will need to surround the Japanese citation and the
> quotations using some isolation using <bdi>...</bdi> or equivalent bidi isolate controls, or an LTR override
> control for the leading quotation mark to get:

I don't see any problems with quotes in Emacs, see above.

> May be some bidi processors may opt for matching quotation mark pairs such as "..." or “...” or „...‟ or «...» or
> »...« or 「...」, but it is well known that this won't work if quotation marks are not paired or use the same
> mirrorable character for the leasing and trailing quotation marks as ”...”,.

They do match here without any problems.