4 ms·

Huh... I never considered that parentheses go the other way around in RTL languages... How do you think the user made the mistake in the first place? It seems

Huh... I never considered that parentheses go the other way around in RTL languages... How do you think the user made the mistake in the first place? It seems like it was edited to "look right" when it was rendered wrong?

sp332 3y ago
(()) isn't a palindrome, but ())( is.
chrismorgan 3y ago
When you say “go the other way around”, it’s important to note that you still use U+0028 "(" LEFT PARENTHESIS as the opening delimiter and U+0029 ")" RIGHT PARENTHESIS as the closing one, despite their names; but when the bidirectional algorithm decides they should be rendered right-to-left, they get replaced with the opposite glyphs, according to the Unicode Bidi_Mirroring_Glyph property, and so LEFT PARENTHESIS is rendered as a right parenthesis. See https://unicode.org/reports/tr9/#Mirroring https://unicode.org/reports/tr9/#Mirroring for description of the process, and https://www.unicode.org/Public/UCD/latest/ucd/BidiMirroring.txt https://www.unicode.org/Public/UCD/latest/ucd/BidiMirroring.... for the full list of mirrorings, including mentioning cases where there is no appropriate mirrored character defined by Unicode (like √—in fact, I think they’re all mathematical notation), and so they suggest the renderer horizontally flip the glyph instead (which isn’t perfect, as things like italic slant will be inverted).
taneliv 3y ago
Try for yourself! It might be very instructive, even if you can't reproduce this exact same issue. Install an RTL locale and keyboard setting (Arabic is more funky with the cursive script where letters change form after you input the _next_ letter, Hebrew is not, so it might be easier to recognize some issues). Either way, you don't need to know the language, just bang on the keyboard to produce some text. Or copy from somewhere. Now try to: enter numbers in the text (they are LTR at least in those two RTL locales). Try to select a passage with both text and numbers. Try to copy and paste words from, say, Arabic Wikipedia in the middle of English text, and vice versa. Enter parenthesis, especially near newlines. I don't know about you, but my intuition about where text will get inserted is sometimes quite wrong. Don't be alarmed if things work differently in different applications. Or perhaps, be. I still haven't figured out how to input RTL and LTR text properly in Slack using Firefox (I don't know which party to blame, even: me, browser, or Slack).
- schoen 3y ago
  The character rendering is much less context-dependent than Arabic, but Hebrew does have a few final forms which are different at the end of a word, so one can't strictly say that Hebrew characters will never change as a result of adding additional text. Just not nearly as much as Arabic characters do! Actually, I don't remember clearly how the different forms are handled by different character sets and if one would have to type them explicitly in some configurations. Surely on typewriters, but maybe not in Unicode?
  - taneliv 3y ago
    True, I forgot those final forms in Hebrew. Perhaps my mind is conflating them with the initial capital letters of sentences and names in most text with Latin letters. On the different forms, https://en.wikipedia.org/wiki/Arabic_script_in_Unicode https://en.wikipedia.org/wiki/Arabic_script_in_Unicode has a short summary. It is possible to type those contextual forms explicitly (they have their own code points), but "presentation forms are present only for compatibility with older standards, and are not currently needed for coding text."

sp332 3y ago

(()) isn't a palindrome, but ())( is.

chrismorgan 3y ago

When you say “go the other way around”, it’s important to note that you still use U+0028 "(" LEFT PARENTHESIS as the opening delimiter and U+0029 ")" RIGHT PARENTHESIS as the closing one, despite their names; but when the bidirectional algorithm decides they should be rendered right-to-left, they get replaced with the opposite glyphs, according to the Unicode Bidi_Mirroring_Glyph property, and so LEFT PARENTHESIS is rendered as a right parenthesis. See https://unicode.org/reports/tr9/#Mirroring https://unicode.org/reports/tr9/#Mirroring for description of the process, and https://www.unicode.org/Public/UCD/latest/ucd/BidiMirroring.txt https://www.unicode.org/Public/UCD/latest/ucd/BidiMirroring.... for the full list of mirrorings, including mentioning cases where there is no appropriate mirrored character defined by Unicode (like √—in fact, I think they’re all mathematical notation), and so they suggest the renderer horizontally flip the glyph instead (which isn’t perfect, as things like italic slant will be inverted).

taneliv 3y ago

Try for yourself! It might be very instructive, even if you can't reproduce this exact same issue. Install an RTL locale and keyboard setting (Arabic is more funky with the cursive script where letters change form after you input the _next_ letter, Hebrew is not, so it might be easier to recognize some issues). Either way, you don't need to know the language, just bang on the keyboard to produce some text. Or copy from somewhere. Now try to: enter numbers in the text (they are LTR at least in those two RTL locales). Try to select a passage with both text and numbers. Try to copy and paste words from, say, Arabic Wikipedia in the middle of English text, and vice versa. Enter parenthesis, especially near newlines. I don't know about you, but my intuition about where text will get inserted is sometimes quite wrong. Don't be alarmed if things work differently in different applications. Or perhaps, be. I still haven't figured out how to input RTL and LTR text properly in Slack using Firefox (I don't know which party to blame, even: me, browser, or Slack).

schoen 3y ago
The character rendering is much less context-dependent than Arabic, but Hebrew does have a few final forms which are different at the end of a word, so one can't strictly say that Hebrew characters will never change as a result of adding additional text. Just not nearly as much as Arabic characters do! Actually, I don't remember clearly how the different forms are handled by different character sets and if one would have to type them explicitly in some configurations. Surely on typewriters, but maybe not in Unicode?
- taneliv 3y ago
  True, I forgot those final forms in Hebrew. Perhaps my mind is conflating them with the initial capital letters of sentences and names in most text with Latin letters. On the different forms, https://en.wikipedia.org/wiki/Arabic_script_in_Unicode https://en.wikipedia.org/wiki/Arabic_script_in_Unicode has a short summary. It is possible to type those contextual forms explicitly (they have their own code points), but "presentation forms are present only for compatibility with older standards, and are not currently needed for coding text."