4 ms·

I have already explained why mathematical alphanumeric symbols exist in the first place [1]. They are an extremely small portion of Unicode; you need way more e

I have already explained why mathematical alphanumeric symbols exist in the first place [1]. They are an extremely small portion of Unicode; you need way more examples. By the way, if we indeed decide to encode characters according to glyphs, we would have to distinguish a double-storey `a` from a single-storey `a` (among others). They have clearly different glyphs, so why shouldn't we? Think about that. [1] https://news.ycombinator.com/item?id=28294032 https://news.ycombinator.com/item?id=28294032

WalterBright 3y ago
> I have already explained But somehow mathematical books have done just fine without any need for such encodings. Meaning in written language is inferred from the context, not the symbol. This is because meanings are infinite in variety, and symbols are finite. > Think about that I did. That's what fonts are for. Fonts come in endless variety, and so cannot be encoded into Unicode. They are an orthogonal property of rendered text. And so is formatting - it's an orthogonal property.
- lifthrasiir 3y ago
  > But somehow mathematical books have done just fine without any need for such encodings. Printed books have no reason to think about encodings. In fact, they can use one-off metal types (or images nowadays) for unusual characters. In return printed books cannot be easily searched if the entry doesn't appear in prepared indices. > Fonts come in endless variety, and so cannot be encoded into Unicode. But some fonts convey semantics. For example a normal text does not distinguish two variants of `a`, but IPA does, so Unicode does encode a single-storey `ɑ` separately and unify a double-storey `a` to the normal lowercase `a`. (p. 299 of the Unicode standard 15.0) Semantics is arguably the only way to judge those cases. If fonts do not matter but glyphs do matter, how would know a particular glyph should be identically encoded to other glyph or not? I think you agree that a double-storey `a` and a single-storey `a` are same characters with different fonts. Semantics is how we decide the "same characters" part!
  - WalterBright 3y ago
    > Printed books have no reason to think about encodings Exactly! It's the visual that matters. If you cannot print Unicode text on a sheet of paper and know its meaning, then Unicode has gone into a ditch. > printed books cannot be easily searched if the entry doesn't appear in prepared indices Are you going to invent a new encoding for every distinct use of the letter 'a'? That's not remotely possible. > But some fonts convey semantics People invent new fonts every day. Hell, I've invented fonts! Your mission to encode them all into Unicode is an instantly hopeless task. Again, semantics are divined from context. I know a mathematical 'i' from the english letter 'i' and the french letter 'i' and the bullet point 'i' and the electric current 'i' by context, and so do you and everyone else. I even use the letter 'A' to represent an Army in my computer game Empire. Nobody has a problem divining the meaning. (and B for Battleship, S for Submarine , etc.)
    - lifthrasiir 3y ago
      > It's the visual that matters. I expect a good search function for my electronic book! > Again, semantics are divined from context. I gave an explicit counterexample. You can't distinguish an IPA `ɑ` (open back unrounded vowel) from an IPA `a` (open front unrounded vowel) with just a context---[hɑt] and [hat] are different pronunciations. So they have to be differently encoded, right? And due to its history, either the "normal" `a` glyph will exactly look like one of them, depending on the font. So we can't have perfectly distinct glyphs for distinct code points anyway. Maybe we need a better rationale, something like semantics...
      - WalterBright 3y ago
        We have many words that are spelled the same, but sound different based on context, like "sow". That isn't a problem. They don't have to be differently encoded. Besides, are you now planning on adding accents and dialect pronunciations, too?
        lifthrasiir 3y ago
        I'm not talking about homonyms (but I wasn't clear enough about that, sorry). I'm talking about the exact alphabets describing pronunciations. Honestly I can't really differentiate [hɑt] and [hat] sounds, but their IPA renditions are clearly different and have to be differently encoded.

WalterBright 3y ago

> I have already explained But somehow mathematical books have done just fine without any need for such encodings. Meaning in written language is inferred from the context, not the symbol. This is because meanings are infinite in variety, and symbols are finite. > Think about that I did. That's what fonts are for. Fonts come in endless variety, and so cannot be encoded into Unicode. They are an orthogonal property of rendered text. And so is formatting - it's an orthogonal property.

lifthrasiir 3y ago
> But somehow mathematical books have done just fine without any need for such encodings. Printed books have no reason to think about encodings. In fact, they can use one-off metal types (or images nowadays) for unusual characters. In return printed books cannot be easily searched if the entry doesn't appear in prepared indices. > Fonts come in endless variety, and so cannot be encoded into Unicode. But some fonts convey semantics. For example a normal text does not distinguish two variants of `a`, but IPA does, so Unicode does encode a single-storey `ɑ` separately and unify a double-storey `a` to the normal lowercase `a`. (p. 299 of the Unicode standard 15.0) Semantics is arguably the only way to judge those cases. If fonts do not matter but glyphs do matter, how would know a particular glyph should be identically encoded to other glyph or not? I think you agree that a double-storey `a` and a single-storey `a` are same characters with different fonts. Semantics is how we decide the "same characters" part!
- WalterBright 3y ago
  > Printed books have no reason to think about encodings Exactly! It's the visual that matters. If you cannot print Unicode text on a sheet of paper and know its meaning, then Unicode has gone into a ditch. > printed books cannot be easily searched if the entry doesn't appear in prepared indices Are you going to invent a new encoding for every distinct use of the letter 'a'? That's not remotely possible. > But some fonts convey semantics People invent new fonts every day. Hell, I've invented fonts! Your mission to encode them all into Unicode is an instantly hopeless task. Again, semantics are divined from context. I know a mathematical 'i' from the english letter 'i' and the french letter 'i' and the bullet point 'i' and the electric current 'i' by context, and so do you and everyone else. I even use the letter 'A' to represent an Army in my computer game Empire. Nobody has a problem divining the meaning. (and B for Battleship, S for Submarine , etc.)
  - lifthrasiir 3y ago
    > It's the visual that matters. I expect a good search function for my electronic book! > Again, semantics are divined from context. I gave an explicit counterexample. You can't distinguish an IPA `ɑ` (open back unrounded vowel) from an IPA `a` (open front unrounded vowel) with just a context---[hɑt] and [hat] are different pronunciations. So they have to be differently encoded, right? And due to its history, either the "normal" `a` glyph will exactly look like one of them, depending on the font. So we can't have perfectly distinct glyphs for distinct code points anyway. Maybe we need a better rationale, something like semantics...
    - WalterBright 3y ago
      We have many words that are spelled the same, but sound different based on context, like "sow". That isn't a problem. They don't have to be differently encoded. Besides, are you now planning on adding accents and dialect pronunciations, too?
      - lifthrasiir 3y ago
        I'm not talking about homonyms (but I wasn't clear enough about that, sorry). I'm talking about the exact alphabets describing pronunciations. Honestly I can't really differentiate [hɑt] and [hat] sounds, but their IPA renditions are clearly different and have to be differently encoded.