Hi Sebastien,

Thanks for your comments, and your thoughts on the proposed deprecation.

It’s worth explicitly considering why we wouldn’t want to steer people away from the TeX-syntax LaTeX fragments, so I am glad you have brought up some reasons. I do not find myself agreeing with them however, and will endeavour to explain why below.

These points seem to have a common thread in wanting to have Org be like LaTeX. I find this sensible, but I think this is a good opportunity to point out that $/$$ are very much second class citizens in LaTeX now, no matter what you may see in old documents.

To quote from David Carlisle (one of the main members of the LaTeX3 team) on tex.stackexchange:

$$ is TeX primitive syntax, which, as others have commented is hard to redefine (in classic TeX there is no command name which triggers entering or leaving display math). LaTeX doesn’t officially support $$. The most noticeable failure if you use the syntax is that the fleqn option will no longer affect the display of the mathematics, it will remain centered rather than being set flush left.

Another member of the LaTeX3 team, Joseph Wright, has made even stronger comments about $-syntax on tex.stackexchange:

I’d note with my ’LaTeX3’ hat on that there is a strong chance we’ll favour \( ... \) to the point of not supporting $...$ for LaTeX3. So in the long term it might be best to get used to \(...\).

In further comments Joseph goes on to say that it is likely that $-syntax will not be dropped outright, but that $$ likely will be. Among other things the $-syntax produces worse error reporting and spacing.

So, to sum up LaTeX currently prefers \(...\) / \[...\] over $ / $$, and it looks like people will be pushed more strongly in this direction in future.

More than anything else, I think this demonstrates why aside from annoyances with the parsing, purely from a user perspective, it would make sense to favour LaTeX-syntax LaTeX fragments.

All the best,
Timothy

From: Sébastien Miquel
Subject: Re: Org Syntax Specification
To: Timothy, org-mode-email
Date: Sat, 15 Jan 2022 20:40:12 +0800

Hi,

The new document seems much clearer. It makes a nice complement to the
manual and we should definitely lose the (draft). Thank you Timothy
for the work.

Lastly, having spent a while looking at the syntax, I’m wondering if we should take this opportunity to mark some of the syntactic elements we’ve become less happy with as (depreciated). I’m specifically thinking of the TeX-style LaTeX fragments which have been a bit of a pain. To quote Nicolas in org-syntax.org:

It would introduce incompatibilities with previous Org versions, but support for $...$ (and for symmetry, $$...$$) constructs ought to be removed.

They are slow to parse, fragile, redundant and imply false positives. — ngz


This quote has been mentioned a few times lately, and no one has yet
spoken in favor of the $…$ syntax, so I'll have a quick go.

It is easier to use, easier to read and more commonly used (and known)
in tex documents (a quick web search for sample tex documents confirms
the latter). Removing this syntax would make org slightly harder to
pick up, with respect to writing scientific documents.

As for the listed shortcomings, I don't think we know whether its
slowness is significant and false positives can be avoided by using
the \dollar entity (possibly ?). In my own use, the only usability
issue I can think of is false negatives while writing : inserting a
space or other such characters at the end of a snippet removes the
fontification (I solve this by modifying the fontification regexps).

Regards,

-- 
Sébastien Miquel