Allow the use of custom operator/function name

[Azercoco]

I would like to convert a mathematical expression with sech inside. sech is actually a typst function but not a LaTeX one, so in the LaTeX code, I need to add \DeclareMathOperator{\sech}{sech}.

It would be nice if this was taken into account by the convertor. Right now, I need to do additionnal pre and post processing to achieve the correct conversion.

[qwinsi]

OK. I will try to make this work

[Azercoco]

After looking into KaTex documentation, the correct way to make it work is to use \newcommand{\sech}{\operatorname{sech}}. This yields the translation into typst to 'op("sech")', while it should only be 'sech'.

From my template, I know at least the following operator are default in typst but not in LateX :

• sech
• csch
• sgn

Ideally, we should compare https://katex.org/docs/supported#math-operators and the Typst predefined operators :

https://typst.app/docs/reference/math/op/.

[Azercoco]

I did a review and the supported ones in typst but not in KaTeX are :

• dim
• id
• im
• mod
• Pr
• sech
• csch

Actually sgn, and csch are supported by neither.

So I would suggest :

• For the previoulsy mentionned operators, convert LaTeX \operatorname{sech} to just typst sech for eg.
• Otherwise, for clarity, instead of converting every LaTeX \operatorname{opr} to op("opr"), create typst preprocessor : #let opr = $op("opr") and then use it as a preamble for the typst code.
• Maybe also automatically convert the \DeclareMathOperator{...} from ansmath to \newcommand{...}{\operatorname{...}}

EDIT, I miss it but actually csch is defined in Typst.

[qwinsi]

Well, I will try to improve it as the following:

• Allow to turn the converter to "non-strict" mode. In such mode, any unrecognized LaTeX command (e.g. \myopr) will be translated to just myopr.
  And the Web App will show additional text area to remind the user to add #let myopr = $op("myopr"); before the Typst math block.
• For operators already supported by Typst (e.g. sech), convert LaTeX \operatorname{sech} to just typst sech instead of op("sech")

[qwinsi]

The improvement described above has been applied. Check it in the Web App.
Ideally, there should be some front-end UI interface to customize the options. I don't have much front-end development skills, so the front-end interface is in the plan but won't be done within recent days.