Hi.
From: Konstantin Ritt <ritt.ks_at_gmail.com> Date: Thu, 7 Jun 2012 13:06:04 +0300 > Yep, forgot to mention that the difference is in that that some paired > quotation characters might be used alone in place of apostrophe, etc. > so that the BPA rules could be relaxed for the quotation marks. > Dunno about their mirroring in all languages. I thought the > BidiMirroring.txt is supposed to list a (language-independent) > characters and their respective mirrored brothers. > UAX#24 section 2.2 "Handling Characters with the Common Script Property" > states: >> In determining the boundaries of a run of text in a given script, programs must resolve any of the special script property values, such >> as Common, based on the context of the surrounding characters. A simple heuristic uses the script of the preceding character, which >> works well in many cases. However, this may not always produce optimal results. For example, in the text "... gamma (γ) is ...", this >> heuristic would cause matching parentheses to be in different scripts. >> >> Generally, paired punctuation, such as brackets or quotation marks, belongs to the enclosing or outer level of the text and should >> therefore match the script of the enclosing text. In addition, opening and closing elements of a pair resolve to the same script property >> values, where possible. The use of quotation marks is language dependent; therefore it is not possible to tell from the character code >> alone whether a particular quotation mark is used as an opening or closing punctuation. For more information, see Section 6.2, >> General Punctuation, of [Unicode]. >> >> Some characters that are normally used as paired punctuation may also be used singly. An example is U+2019 right single quotation >> mark, which is also used as apostrophe, in which case it no longer acts as an enclosing punctuation. An example from physics would >> be <ψ| or |ψ>, where the enclosing punctuation characters may not form consistent pairs. > IIUC, this is the same problem like the one PRI #231 is intended to solve. > For the cases like "a«b»" one would expect similar results provided by > the UBA and the script itemization. > Konstantin 2012/6/7 Philippe Verdy <verdy_p_at_wanadoo.fr>: >> Their pairing and mirroring is not appropriate for all languages using them. >> >> 2012/6/7 Konstantin Ritt <ritt.ks_at_gmail.com>: >>> Actually, they have a respective entries in the BidiMirroring.txt: >>> 00AB; 00BB # LEFT-POINTING DOUBLE ANGLE QUOTATION MARK >>> 00BB; 00AB # RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK >>> and mapped into gc=Pi and gc=Pf. >>> Even without the per-language tailoring, it seems like a good basic >>> approximation, no? Phillipe is correct; Wikipedia gives some examples of language-specific variation in opening and closing quotation marks: http://en.wikipedia.org/wiki/Non-English_usage_of_quotation_marks (also of course as Konstantin notes the single quotation marks are used in some languages as apostrophes to indicate possession) I have not used say French-style quotations in facebook where parentheses get displayed at the wrong places if used in mixed right-to-left and left-to-right text. So I dunno what happens to quotation marks in mixed-directionality text yet. Best, --C. E. Whitehead [email protected]
