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Comment by littlestymaar | Hacker News Reader

Only tangentially related, but it's a question that have bothered me for a while: Is there a reason why composite Math symbol aren't part of Unicode? Things like series, limits or integrals look like a really good fit for this kind of composition, and you could get rid of mathjax for 80% of its usage.

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I gotta think it's because all the math you mention cannot render within a normal line height. That's not the end of the world for rendering, but maybe that counts as a bridge too far in Unicode? Or maybe it just boils down to "because it doesn't yet" and as soon as someone makes a good proposal it'll happen

Unicode already has a bunch of things that extend the height like those "corrupted text" generators.

Those are a ton of combining accents put together. Crucially: they don't make the line any taller—that's what makes them so hard to read! An integral should be a little taller than the line height but you still want the integral's limits to be legible. Maybe I'm being too prescriptive; ∫₀¹𝑥 𝑑𝑥 would read ok if that 1 were stacked on top of the 0 without any other changes.

My apologies if HN's formatter strips the special characters (edit: it didn't yay!): I wrote integral sign, subscript 0, superscript 1, math italic x, thin space, math italic d, math italic x. And maybe the idea is we should use words like "the integral from zero to one of x with respect to x." IDK.

There is a proposal by the Julia language team

https://github.com/stevengj/subsuper-proposal

Everybody, if you're a somebody in your field, please go sign this.

I guess the question is how much typesetting do you want to stick into unicode? It works OK for emoji because the results are always simple: it's just another individual emoji, with the same size & characteristics as the original.

That said unicode is not free from typesetting weirdness, see the character ﷽.

consider the following:

𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫𒐫

As noted, it's a bit more complicated than just putting things above or below a symbol. Also, if you look closer at the output from MathJax, you'll notice things like the setting of x+y=z has slightly different spacing around the + than the =. For that matter, properly typeset mathematics will also the spaces around the colons differently in, e.g., f: X → { y ∊ *R* : |y| < 1 }. Math typesetting is not a simple matter. I'd also note that the existence of, e.g., ² or ₆ in Unicode is more a result of allowing the mapping of legacy encodings and that there is a preference in Unicode that in general, superscripts and subscripts not be handled through encodings but rather through the layout engine of the application which is why there is no superscripted decimal point or other such characters.

1) Combining emoji compose into a finite and reasonably small set of combined symbols. The set of mathematical formulas isn't finite in the same kind of way.

2) Layout of mathematical formulas is reasonably complicated. It doesn't make sense to force that complexity to be included in every text layout engine.

There is UnicodeMath[1], which was developed by Microsoft and is the default representation used by the Word equation editor.

It looks like this:

e=lim┬(n→∞)⁡(1+1/n)^n

f(x)=∑_(k=-∞)^∞〖c_n e^(ⅈkx)〗

∫_(-∞)^(+∞)〖exp⁡(-a/2 x^2) ⅆx〗=√(2π/a)

I find it quite readable, even for quite complicated formulae like the above. You can also replace the unicode symbols with Latex-style escape strings, like \sum or \below.

[1]: https://unicode.org/notes/tn28/UTN28-PlainTextMath-v3.1.pdf

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