8 ms·

I love this. There are lots of characters in Unicode I'd love to know the history of, but searching for such things is hard, at best. The one I've stumbled ac

I love this. There are lots of characters in Unicode I'd love to know the history of, but searching for such things is hard, at best. The one I've stumbled across recently are the "Negative Squared Latin Capital Letter" (1F170 - 1F189 [1]). The 26 letters are there, but "A", "B", "O", and "P" are special. Blood types and a parking symbol. Sure, but why? Why was it decided we needed all of the Latin letters in inverted squares, except those? Why aren't they their own symbol? I'm not complaining here, I just want to know the history. I'd also love to know the history of the other Latin letter ranges. It feels super odd to me to have, say the "Mathematical Bold Fraktur" range of characters (1D56C - 1D59F [2]). What's the history of including a font in Unicode? Why did we stop with the few that are in there? This is probably somewhere online, but I can't find it. [1] https://unicode-search.net/unicode-namesearch.pl?term=negative+squared https://unicode-search.net/unicode-namesearch.pl?term=negati... [2] https://unicode-search.net/unicode-namesearch.pl?term=mathematical+bold+fraktur https://unicode-search.net/unicode-namesearch.pl?term=mathem...

chrisoverzero 6y ago
>Sure, but why? Some OSes display some unicode characters as emoji-default. These characters were selected for that for exactly the reason you surmise. There’s a [text presentation selector][] to enforce the text variation. This is also useful for making (yellow triangle with exclamation point inside) become (single color triangle outline with same-color exclamation point inside). ETA: Ah, OK, here’s a post with pictures demonstrating this: https://stackoverflow.com/questions/48534667/how-to-display-a-colored-emoji/48535790#48535790 https://stackoverflow.com/questions/48534667/how-to-display-... [text presentation selector]: http://www.unicode.org/reports/tr51/#def_text_presentation_selector http://www.unicode.org/reports/tr51/#def_text_presentation_s...
- kps 6y ago
  > Some OSes display some unicode characters as emoji-default. Those characters have the Emoji_Presentation Unicode property, as listed in https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.txt https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.t... If a site wished to exclude garish blobs from comments while permitting textual symbols, that would be the right way to do it.
plutonic 6y ago
Fraktur is used in mathematics, chiefly when discussing/denoting Lie groups. I've listed some sources but you can probably Google for more. [0] https://en.wikipedia.org/wiki/Fraktur#After_1941 https://en.wikipedia.org/wiki/Fraktur#After_1941 [1] https://mathoverflow.net/questions/87627/fraktur-symbols-for-lie-algebras https://mathoverflow.net/questions/87627/fraktur-symbols-for...
- banana_giraffe 6y ago
  That's fair, but why stop there? The example that comes to mind is "Courier 12pt is the only font ever for screenplays". It's required to convey a screenplay, to my mind, like using Fraktur is required in the math space. Despite what it may seem like, I'm really not trying to mis-parse the reasons here, I'm honestly trying to figure out where the line is, and why it's there.
  - kps 6y ago
    Historically, a few were included in the Letterlike Symbols block¹ because they were present in some pre-Unicode character set. Much later it was argued that since a few were present, they all should be present. ¹ https://en.wikipedia.org/wiki/Letterlike_Symbols https://en.wikipedia.org/wiki/Letterlike_Symbols
    - chungy 6y ago
      Also note that these selective ones were part of the basic multilingual plane, where space was always a bit at a premium. They were assigned before Unicode expanded to have 17 complete 16-bit planes and space stopped being a problem.
  - thotsBgone 6y ago
    The introduction of the Fraktur font introduces different meaning. 'R' in Fraktur would mean something different than R in another font in the same text.
    - 6y ago
deleted 6y ago
[deleted]
the_mitsuhiko 6y ago
> The one I've stumbled across recently are the "Negative Squared Latin Capital Letter" (1F170 - 1F189 [1]). The 26 letters are there, but "A", "B", "O", and "P" are special. In which way are they special? As far as unicode is concerned they are all the same. It's just that some have an emoji rendering variant for the blood type reasons. The rendering can be picked through representation characters: http://www.unicode.org/reports/tr51/#def_text_presentation_selector http://www.unicode.org/reports/tr51/#def_text_presentation_s...
neolog 6y ago
I don't see what's special about ABOP on that page?
- banana_giraffe 6y ago
  Interesting, every font I've seen renders them like this: https://imgur.com/a/ZPBfaK0 https://imgur.com/a/ZPBfaK0 I thought it was suggested to render them like that from Unicode somewhere, but it's 100% possible I'm making that part up.
  - lilyball 6y ago
    My recollection is for the textual characters that got repurposed as emoji, it’s implementation-defined as to whether the character defaults to text or emoji but that most renderers opt for emoji (which I believe is copying Apple’s decision here). There are variation selectors you can use to force textual or emoji presentation.
    - kps 6y ago
      It's not implementation defined, i's defined by the Emoji_Presentation property in https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.txt https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.t... Some implementations are just wrong.
      - lilyball 6y ago
        That file is new in Unicode 13. Also I think it might be based on Apple's behavior. I just tested every single emoji codepoint listed there, and it's almost entirely consistent with Apple's default rendering. And the very few exceptions (like ) actually seem to depend on whether the text renderer is styled or not, where it becomes emoji in styled fields (like Spotlight) and text in plain-text fields (like this comment box). This seems to only be done for the small handful of pre-existing text symbols that got turned into emoji and given the Emoji_Presentation property.
  - AnssiH 6y ago
Someone 6y ago
The committee thinks/thought that the Fraktur letters aren’t just a different way to write letters, but symbols with a different meaning, just as ℂ, ℕ, and ℝ aren’t a different way to write C, N and R. (And yes, they included not only 𝔸𝔹ℂ𝔻𝔼𝔽𝔾ℍ𝕀𝕁𝕂𝕃𝕄ℕ𝕆ℙℚℝ𝕊𝕋𝕌𝕍𝕎𝕏𝕐ℤ, but also 𝕒𝕓𝕔𝕕𝕖𝕗𝕘𝕙𝕚𝕛𝕜𝕝𝕞𝕟𝕠𝕡𝕢𝕣𝕤𝕥𝕦𝕧𝕨𝕩𝕪𝕫 and 𝟘𝟙𝟚𝟛𝟜𝟝𝟞𝟟𝟠𝟡 in Unicode. In iOS Safari, using the font for entering HN comments, ℂℍℙℚ renders a bit taller and bolder for me. ℝ and ℤ render taller, but not bolder. Why beats me.) I agree with them on ℂ, ℕ, and ℝ. I also think that makes it hard to disagree with them on the Fraktur letters.
- BlueTemplar 6y ago
  What bothers me is that for some reason only some latin letters and numbers are available as subscripts and superscripts...
  - jml7c5 6y ago
    Most of the Latin subscript glyphs are from the Phonetic Extensions block. They only added those that were actually used in various phonetic notations. This Wikipedia page has a good list of why various ones were added, in addition to those from the Subscripts and Superscripts block: https://en.wikipedia.org/wiki/Unicode_subscripts_and_superscripts#Other_superscript_and_subscript_characters https://en.wikipedia.org/wiki/Unicode_subscripts_and_supersc...
- Kwpolska 6y ago
  > In iOS Safari, using the font for entering HN comments, ℂℍℙℚ renders a bit taller and bolder for me. ℝ and ℤ render taller, but not bolder. Why beats me. Font fallback. HN specifies Verdana, Geneva, sans-serif. Geneva has the six characters mentioned. The rest will be rendered using a different font that covers more parts of Unicode, or that covers Unicode math specifically. With the built-in system fonts, that would be Cambria Math on Windows and one of the STIX fonts on macOS. (Source: Firefox → Inspect Element → Fonts tab of the right Inspector pane. Chrome can do that too in a slightly different place, macOS Safari is too user-hostile to have this feature.)
yenwodyah 6y ago
There's a popular belief in Japan that a person's blood type influences their personality[0]. This probably made Japanese emoji designers add them to their pre-unicode emoji sets, which then got rolled into the first set of unicode emoji in 2010[1], along with a bunch of other Japanese symbols. [0] https://en.wikipedia.org/wiki/Blood_type_personality_theory https://en.wikipedia.org/wiki/Blood_type_personality_theory [1] https://emojipedia.org/unicode-6.0/ https://emojipedia.org/unicode-6.0/
pbhjpbhj 6y ago
Weird that this comes up today. My Steam handle has an O and I used "negative squared Latin" characters -- I was investigating this yesterday (I found no answers!). Last year my Steam name showed properly on MS Win10 and on Kubuntu. About 6 months ago Win 10 started showing it with the O as red. Last week the red O doesn't show at all in one part of Steam but shows white in another part. I copied the symbols to a Unicode decoder and it showed the O name with a {blood red} modifier, something like that. I searched briefly but couldn't find the symbol without the red colour, but it only shows red in some places: I'd pasted it into the search bar in Firefox (on Kubuntu), it showed as a number-square (1Fxxx) but then after searching it showed as the red-O character. Utf8 is weird.
- kilburn 6y ago
  In case you enjoy the technical pedantry: UTF-8 is "just" an encoding scheme to represent the characters defined in the Unicode standard. There are other schemes in the standard (like UTF-16 or UCS-4). Your issue here is with the characters and their representation, not with the specific encoding. Hence, what you wanted to say is: "Unicode is weird" ;)
  - framecowbird 6y ago
    This is the most nicely delivered pedantry I've ever read, kudos!
- Kwpolska 6y ago
  Here you go: o = "\U0001F17E" black = o + "\ufe0e" red = o + "\ufe0f" print(black, red) HN seems to strip the special sequences, here it is on a pastebin instead: https://paste.debian.net/1169485/ https://paste.debian.net/1169485/ More details: http://unicode.org/faq/vs.html http://unicode.org/faq/vs.html http://www.unicode.org/Public/emoji/5.0/emoji-variation-sequences.txt http://www.unicode.org/Public/emoji/5.0/emoji-variation-sequ...
  - bmn__ 6y ago
    Kwpolska, most of your comments since 2011 are shadow banned. Occasionally HN readers vouch them back into visibility.

chrisoverzero 6y ago

>Sure, but why? Some OSes display some unicode characters as emoji-default. These characters were selected for that for exactly the reason you surmise. There’s a [text presentation selector][] to enforce the text variation. This is also useful for making (yellow triangle with exclamation point inside) become (single color triangle outline with same-color exclamation point inside). ETA: Ah, OK, here’s a post with pictures demonstrating this: https://stackoverflow.com/questions/48534667/how-to-display-a-colored-emoji/48535790#48535790 https://stackoverflow.com/questions/48534667/how-to-display-... [text presentation selector]: http://www.unicode.org/reports/tr51/#def_text_presentation_selector http://www.unicode.org/reports/tr51/#def_text_presentation_s...

kps 6y ago
> Some OSes display some unicode characters as emoji-default. Those characters have the Emoji_Presentation Unicode property, as listed in https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.txt https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.t... If a site wished to exclude garish blobs from comments while permitting textual symbols, that would be the right way to do it.

plutonic 6y ago

Fraktur is used in mathematics, chiefly when discussing/denoting Lie groups. I've listed some sources but you can probably Google for more. [0] https://en.wikipedia.org/wiki/Fraktur#After_1941 https://en.wikipedia.org/wiki/Fraktur#After_1941 [1] https://mathoverflow.net/questions/87627/fraktur-symbols-for-lie-algebras https://mathoverflow.net/questions/87627/fraktur-symbols-for...

banana_giraffe 6y ago
That's fair, but why stop there? The example that comes to mind is "Courier 12pt is the only font ever for screenplays". It's required to convey a screenplay, to my mind, like using Fraktur is required in the math space. Despite what it may seem like, I'm really not trying to mis-parse the reasons here, I'm honestly trying to figure out where the line is, and why it's there.
- kps 6y ago
  Historically, a few were included in the Letterlike Symbols block¹ because they were present in some pre-Unicode character set. Much later it was argued that since a few were present, they all should be present. ¹ https://en.wikipedia.org/wiki/Letterlike_Symbols https://en.wikipedia.org/wiki/Letterlike_Symbols
  - chungy 6y ago
    Also note that these selective ones were part of the basic multilingual plane, where space was always a bit at a premium. They were assigned before Unicode expanded to have 17 complete 16-bit planes and space stopped being a problem.
- thotsBgone 6y ago
  The introduction of the Fraktur font introduces different meaning. 'R' in Fraktur would mean something different than R in another font in the same text.
  - 6y ago

deleted 6y ago

[deleted]

the_mitsuhiko 6y ago

> The one I've stumbled across recently are the "Negative Squared Latin Capital Letter" (1F170 - 1F189 [1]). The 26 letters are there, but "A", "B", "O", and "P" are special. In which way are they special? As far as unicode is concerned they are all the same. It's just that some have an emoji rendering variant for the blood type reasons. The rendering can be picked through representation characters: http://www.unicode.org/reports/tr51/#def_text_presentation_selector http://www.unicode.org/reports/tr51/#def_text_presentation_s...

neolog 6y ago

I don't see what's special about ABOP on that page?

banana_giraffe 6y ago
Interesting, every font I've seen renders them like this: https://imgur.com/a/ZPBfaK0 https://imgur.com/a/ZPBfaK0 I thought it was suggested to render them like that from Unicode somewhere, but it's 100% possible I'm making that part up.
- lilyball 6y ago
  My recollection is for the textual characters that got repurposed as emoji, it’s implementation-defined as to whether the character defaults to text or emoji but that most renderers opt for emoji (which I believe is copying Apple’s decision here). There are variation selectors you can use to force textual or emoji presentation.
  - kps 6y ago
    It's not implementation defined, i's defined by the Emoji_Presentation property in https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.txt https://www.unicode.org/Public/13.0.0/ucd/emoji/emoji-data.t... Some implementations are just wrong.
    - lilyball 6y ago
      That file is new in Unicode 13. Also I think it might be based on Apple's behavior. I just tested every single emoji codepoint listed there, and it's almost entirely consistent with Apple's default rendering. And the very few exceptions (like ) actually seem to depend on whether the text renderer is styled or not, where it becomes emoji in styled fields (like Spotlight) and text in plain-text fields (like this comment box). This seems to only be done for the small handful of pre-existing text symbols that got turned into emoji and given the Emoji_Presentation property.
- AnssiH 6y ago

Someone 6y ago

The committee thinks/thought that the Fraktur letters aren’t just a different way to write letters, but symbols with a different meaning, just as ℂ, ℕ, and ℝ aren’t a different way to write C, N and R. (And yes, they included not only 𝔸𝔹ℂ𝔻𝔼𝔽𝔾ℍ𝕀𝕁𝕂𝕃𝕄ℕ𝕆ℙℚℝ𝕊𝕋𝕌𝕍𝕎𝕏𝕐ℤ, but also 𝕒𝕓𝕔𝕕𝕖𝕗𝕘𝕙𝕚𝕛𝕜𝕝𝕞𝕟𝕠𝕡𝕢𝕣𝕤𝕥𝕦𝕧𝕨𝕩𝕪𝕫 and 𝟘𝟙𝟚𝟛𝟜𝟝𝟞𝟟𝟠𝟡 in Unicode. In iOS Safari, using the font for entering HN comments, ℂℍℙℚ renders a bit taller and bolder for me. ℝ and ℤ render taller, but not bolder. Why beats me.) I agree with them on ℂ, ℕ, and ℝ. I also think that makes it hard to disagree with them on the Fraktur letters.

BlueTemplar 6y ago
What bothers me is that for some reason only some latin letters and numbers are available as subscripts and superscripts...
- jml7c5 6y ago
  Most of the Latin subscript glyphs are from the Phonetic Extensions block. They only added those that were actually used in various phonetic notations. This Wikipedia page has a good list of why various ones were added, in addition to those from the Subscripts and Superscripts block: https://en.wikipedia.org/wiki/Unicode_subscripts_and_superscripts#Other_superscript_and_subscript_characters https://en.wikipedia.org/wiki/Unicode_subscripts_and_supersc...
Kwpolska 6y ago
> In iOS Safari, using the font for entering HN comments, ℂℍℙℚ renders a bit taller and bolder for me. ℝ and ℤ render taller, but not bolder. Why beats me. Font fallback. HN specifies Verdana, Geneva, sans-serif. Geneva has the six characters mentioned. The rest will be rendered using a different font that covers more parts of Unicode, or that covers Unicode math specifically. With the built-in system fonts, that would be Cambria Math on Windows and one of the STIX fonts on macOS. (Source: Firefox → Inspect Element → Fonts tab of the right Inspector pane. Chrome can do that too in a slightly different place, macOS Safari is too user-hostile to have this feature.)

yenwodyah 6y ago

There's a popular belief in Japan that a person's blood type influences their personality[0]. This probably made Japanese emoji designers add them to their pre-unicode emoji sets, which then got rolled into the first set of unicode emoji in 2010[1], along with a bunch of other Japanese symbols. [0] https://en.wikipedia.org/wiki/Blood_type_personality_theory https://en.wikipedia.org/wiki/Blood_type_personality_theory [1] https://emojipedia.org/unicode-6.0/ https://emojipedia.org/unicode-6.0/

pbhjpbhj 6y ago

Weird that this comes up today. My Steam handle has an O and I used "negative squared Latin" characters -- I was investigating this yesterday (I found no answers!). Last year my Steam name showed properly on MS Win10 and on Kubuntu. About 6 months ago Win 10 started showing it with the O as red. Last week the red O doesn't show at all in one part of Steam but shows white in another part. I copied the symbols to a Unicode decoder and it showed the O name with a {blood red} modifier, something like that. I searched briefly but couldn't find the symbol without the red colour, but it only shows red in some places: I'd pasted it into the search bar in Firefox (on Kubuntu), it showed as a number-square (1Fxxx) but then after searching it showed as the red-O character. Utf8 is weird.

kilburn 6y ago
In case you enjoy the technical pedantry: UTF-8 is "just" an encoding scheme to represent the characters defined in the Unicode standard. There are other schemes in the standard (like UTF-16 or UCS-4). Your issue here is with the characters and their representation, not with the specific encoding. Hence, what you wanted to say is: "Unicode is weird" ;)
- framecowbird 6y ago
  This is the most nicely delivered pedantry I've ever read, kudos!
Kwpolska 6y ago
Here you go: o = "\U0001F17E" black = o + "\ufe0e" red = o + "\ufe0f" print(black, red) HN seems to strip the special sequences, here it is on a pastebin instead: https://paste.debian.net/1169485/ https://paste.debian.net/1169485/ More details: http://unicode.org/faq/vs.html http://unicode.org/faq/vs.html http://www.unicode.org/Public/emoji/5.0/emoji-variation-sequences.txt http://www.unicode.org/Public/emoji/5.0/emoji-variation-sequ...
- bmn__ 6y ago
  Kwpolska, most of your comments since 2011 are shadow banned. Occasionally HN readers vouch them back into visibility.