new package eqnlines reimplementing and extending equation environments of amsmath

[nbeisert]

I've been working on a reimplementation and extension of the amsmath functionality on equation environments which is nearing completion as a preview version, see intended abstract below. With this note, I wanted to give a heads-up to the Latex project about it. I plan to upload to CTAN tomorrow evening, and if anyone is interested in a last-minute inspection, I could send it upon request.

In short, eqnlines is meant to be used alongside amsmath for the many other features that the latter provides. It is backward compatible with the amsmath equations to a large extent (except for split and some odd nesting), only minor changes should be needed if this package were to be added to existing documents. It can be instructed to overwrite the amsmath equations environments or leave them in place untouched. It adds some options and flexibility (see below) that I wanted to have but that did not fit as an outside extension onto amsmath. It also fixes some issues of the amsmath implementation.

In this early stage, there will be room for adjustments, e.g. to implement or cooperate with PDF tagging (I would need to understand the workings first and probably would need help; I believe the implementation would be analogous to what would be required for amsmath equations).

eqnlines is a LaTeX2e package providing a framework for typesetting single- and multi-line equations which extends the established equation environments of LaTeX and the amsmath package with many options for convenient adjustment of the intended layout. In particular, the package adds flexible schemes for numbering, horizontal alignment and semi-automatic punctuation, and it improves upon the horizontal and vertical spacing options. The extensions can be used and adjusted through optional arguments and modifiers to the equation environments as well as global settings.

[davidcarlisle]

Thanks for your support of LaTeX. Good luck with your package, please do try to add tagging support sooner rather than later.

We can not really offer support to contributed packages at this stage, but you can hopefully find inspiration on places where it would be good to use the supplied hooks/sockets to enable tagging by looking at

https://github.com/latex3/latex2e/blob/develop/required/latex-lab/latex-lab-amsmath.dtx

and related files.

You could also add an entry (presumably "incompatible" for now) for your package at

https://latex3.github.io/tagging-project/tagging-status/full

(The YAML file for that data is linked from the page.)

[nbeisert]

Thanks for pointing out latex-lab-amsmath.dtx, that should help to get started.

[u-fischer]

I made some short tests with tagging and the package is currently incompatible. I opened a PR for an entry in the tagging status: latex3/tagging-project#805