pandoc-lua-crossref

Pandoc Lua filter for cross-references. Faster than the non-Lua alternatives. Currently only supports HTML output. Very much a WIP and yet to be tested thoroughly.

Usage

Markdown input

In order to reference an element, it must have an Id and be numbered. Sections, figures, tables, and equations are automatically numbered, unless they have the class unnumbered.

Specifying section and figure Ids

Section and figure Ids are specified as they would normally be in Pandoc's Markdown:

# A section {#sec}

![Figure caption.](figure.jpg){#fig}

Specifying equation Ids

$$
E=mc^2
$${#einstein .class key="val"}

Specifying table Ids

Table: Table caption. {#id .class key=val}

FirstCol    SecondCol
----------  -----------
FirstCell   SecondCell

Cross-referencing syntax

The syntax used for cross-referencing items is briefly presented below using a series of examples.

Pandoc's Markdown	Output
See #figid. See #eqid.	See Fig. 1. See Eqn. (1).
See [#figid, #figid2, and #figid3].	See Figs. 1, 2, and 3.
See [#figid and #figid2 or #figid3].	See Figs. 1 and 2 or 3.
See [#figid; #figid2; #figid3].	See Figs. 1, 2, and 3.
See [#figid\; #figid2\; #figid3].	See Figs. 1; 2; 3.
See -#figid.	See 1.

No particular Id naming convention is assumed - the user is free to use a naming convention like #sec:id for section Ids, or @#fig:id for figure Ids, but can also choose not to do so. The cross-reference's prefix ("Sec.", "Fig.", "Eqn.", or "Tbl.") is inferred from the type of element that the Id references.

License

© 2025 R. N. West. Released under the GPL version 2 or greater.