Incorrect latex generated for \notsubset in editor

[jaltekruse]

Calling .latex() on a Mathquill editor that contains \notsubset will generate \not \subset.

Planning on trying to debug into the library to try to find a cause, but thought it was worth reporting as I saw it.

[kschaefe]

Is there some visual difference between \notsubset and \not\subset? Or are you just concerned that that LaTeX is being transformed (normalized) and you weren't expecting that?

[jaltekruse]

The original symbol is a subset symbol with a line through it. The resultant latex generates a separate "not" and "subset" symbol. It looks like there is some code that is finding subwords in symbol names when generating latex, but I would assume it is already in some tree representation that should have a clear separation between different symbols. So it seems odd that anything would need to be parsed out of the in memory representation to generate the latex.

[jaltekruse]

I realized this isn't incorrect latex, it is a compound symbol that isn't being recognized by the parser. The proper latex for the symbol is \not\subset, but these two commands together should become one symbol. Will try to take a look at the parser soon to understand how to fix it. @laughinghan is there support for other cases like this in the parser today that I could look at?

[jaltekruse]

This is also an issue for all of the number sets like \R, \N, \Z
They all produce symbols like \mathbb{Z} that are valid latex, but not currently parseable by MathQuill.

[kevinbarabash]

This also breaks copy/pasting of the \notsubset symbol since when you paste it, what's being pasted is \neg\subset.

[jaltekruse]

Part of this was fixed here the symbols for sets of numbers like \R, \N, \Z - #910

Still need to fix all of the symbols that have a preceding \not, there are several beyond \not\subset. Testing things out on overleaf, it appears you can put a \not before just about any symbol to get a version of it with a line through it. So for compatibility with Latex we may want to look at implementing this in a generic way while fixing it, rather than just fixing it for the few symbols with unicode versions of the symbols with a slash through them. For example, while the spacing kind of sucks, this is apparently valid latex.

\not a

Which produces this:

[jaltekruse]

And if we do decide to go that route, this is then kind of related to implementing \cancel #953

[sharkx]

This also breaks copy/pasting of the \notsubset symbol since when you paste it, what's being pasted is \neg\subset.

I'm having the same issue in a different context. I have created a very simple plugin for the summernote editor which allows insert and edit of existing elements.

When I enter the symbol, I need to type \nsup, and the latex I get back is \not\subset.
But if I go back and edit and use \not\subset to initialize the input field, it gets transformed to \neg\subset.
Any hints on how to avoid or fix this ?
Thank you.