The situation reminds me of how Julia’s evolution was guided in some aspects by some opinionated and vocal {Python, R, MATLAB} developers who never had any intention of transitioning to Julia, whether or not their advice was implemented.
Case in point: backslashes and braces in TeX were there for a reason. You can say they make TeX code look ugly, and you would not be wrong. But when you throw them away without addressing the reason they were introduced, well, you end up with blog posts like this one.
$ f_\abs{x} $
$ f_\pi{x} $
In fact, not using backslashes for symbols can actually give an _edge_ with this problem because it would allow distinguishing `pi` and `#abs` (option E in the post).
I had a similar dilemma before I released 1.0.0 last spring, and decided against special cases like these. In Mathup binary operators (^, _, and /) always operate on exactly one group after the operator, regardless of (what I believe is) the author’s intention. So 1/2(x, y) is the same as 1/x(i, j) is the same as 1/f(x, y). I only have a couple of exceptions regarding spacing on trig functions, and (what I believe is) the differential operator. But if you want an implicit group to e.g. under a fraction, in a superscript, you must either denote that with spaces e^ x-1, or with parens e(x-1) [I courteously drop the parens from the output in these troubled expressions].
I'm pretty sure that's how LyX does it, possibly others as well.
- The use of space character to also act as the escape character (latex use backslash) [1]. Not only does it cause confusion, I have to now escape everything $F=ma$ become $ F = m a $ in typst. Complex math equations will be complex no matter what - why make simple equations harder to type to make it slightly easier to type complex ones.
- The lack of these grouping brackets (latex uses curly parenthesis).
What I want from my typesetting language is "typsetting completeness". While there might be sane defaults, I want to be able to control every decision made by the typesetter by escaping and grouping things as needed. If the language doesn't have these features, by definition, it is not complete.
[1] Latex also has to use space to act as ending delimiters. $\alpha x$ is correct and $\alpha\beta$ is correct, but $\alphax$ is not. But the solution to this is to allow $αx$ which some flavors of tex do.
For me, breaking from not just a 40-year-old history of mathematical typesetting but also from the American Mathematical Society recommendations is the dagger. Plus doubling work if you want to reuse what you wrote to render MathJax or KaTeX.
> $\alpha x$ is correct and $\alpha\beta$ is correct, but $\alphax$ is not.
Like you said, braces can be used so all of the following are valid: ${\alpha}x$, $\alpha{x}$ or the odd $\alpha{}x$.
AsciiMath (what my tool was inspired by) tries to be smart about this by parsing a/f(x) differently from a/x(f) and it looks like typst is making the same choose. I on the other hand opted to rather stay consistent. My reasoning is that the tool is fast enough, and I rarely (actually never) type my math expressions outside of an interactive experience where I can’t view the rendered result as I type, so I can spot my mistakes immediately (usually fixed by adding a space, or surrounding something with parens).
Then LaTeX is not complete. Macros don’t have to respect the grouping provided by curly braces in math mode, therefore you only have the illusion of control. Nobody in practice actually inspects the full package dependency chain needed to typeset a nontrivial document.
Here’s a proof of concept: https://tex.stackexchange.com/questions/748416/how-can-i-aut...
That said, Typst has many good things, like easy to write methods, which this new language should adopt.
I feel like this is a lesson people keep learning over and over across programming languages: don't let your syntax try to infer the intended meaning of what was typed, just do something simple and predictable.
So (b) seems like the only sane choice, but having the grouping operation being e^(abs(x)) is also crazy. You need something like TeX's e^{abs(x)}.
Personally I think the "best" workaround for this is to decouple the text representation and the representation the editing happens in. Allow people to type e^abs(x) and then the editor translates that into e^{abs(x)} while letting you edit it as an exponential, but if you're working on the underlying text file then you have to write e^{abs(x)}. For that matters, you can just have the editor represent it as a literal superscript.
(My hunch is that this is generally much-needed across languages: let the editor do some of the parsing work. I think there's much to be gained by separating the two, because you can keep the parser of the actual language simple while still getting all your editing-efficiency improvements out of the editor).