pandoc-crossref: Pandoc filter for cross-references

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pandoc-crossref is a pandoc filter for numbering figures, equations, tables and cross-references to them.

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Dependencies base (>=4.2 && <5), bytestring (>=0.9 && <0.11), containers (>=0.1 && <0.6), data-default (>=0.4 && <0.6), mtl (>=1.1 && <2.3), pandoc (>=1.13 && <1.16), pandoc-crossref, pandoc-types (>= && <1.13), template-haskell, yaml (>=0.8 && <0.9) [details]
License GPL-2.0-only
Author Nikolay Yakimov
Category Text
Source repo head: git clone
this: git clone v0.1.5.2)
Uploaded by lierdakil at 2015-09-27T21:08:16Z
Distributions Arch:, NixOS:
Reverse Dependencies 1 direct, 0 indirect [details]
Executables pandoc-crossref
Downloads 48824 total (249 in the last 30 days)
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Status Docs available [build log]
Last success reported on 2015-09-30 [all 1 reports]

Readme for pandoc-crossref-

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pandoc-crossref filter

pandoc-crossref is a pandoc filter for numbering figures, equations, tables and cross-references to them.

Input file (like can be converted into html, latex, pdf, md or other formats.

Optionally, you can use cleveref for latex/pdf output, e.g. cleveref pdf, cleveref latex, and listings package, e.g. listings pdf, listings latex

You can also enable per-chapter numbering (as with --chapters for latex output). You need to specify -M chapters for non-latex/pdf output however. Examples: html, markdown, latex, pdf.

Tested with pandoc 1.13.2 and 1.14.

This work is inspired by pandoc-fignos and pandoc-eqnos by @tomduck.

This package tries to use latex labels and references if output type is LaTeX. It also tries to supplement rudimentary LaTeX configuration that should mimic metadata configuration by setting header-includes variable.


Syntax is loosely based on discussion in

Image labels


To label an (implicit) figure, append {#fig:label} (with label being something unique to reference this figure by) immediately after image definition.

This only works on implicit figures, i.e. an image occurring by itself in a paragraph (which will be rendered as a figure with caption by pandoc)

Image block and label can be separated by one or more spaces.

Equation labels

$$ math $$ {#eq:label}

To label a display equation, append {#eq:label} (with label being something unique to reference this equation by) immediately after math block.

This only works if display math and label specification are in a paragraph of its own.

Math block and label can be separated by one or more spaces.

Table labels

a   b   c
--- --- ---
1   2   3
4   5   6

: Caption {#tbl:label}

To label a table, append {#tbl:label} at the end of table caption (with label being something unique to reference this table by). Caption and label must be separated by at least one space.

Section labels

You can also reference sections of any level. Section labels use native pandoc syntax, but must start with "sec:", e.g.

# Section {#sec:section}

You can also use autoSectionLabels variable to automatically prepend all section labels (automatically generated with pandoc included) with "sec:". Bear in mind that references can't contain periods, commas etc, so some auto-generated labels will still be unusable.

Code Block labels

There are a couple options to add code block labels. Those work only if code block id starts with lst:, e.g. {#lst:label}

caption attribute

caption attribute will be treated as code block caption. If code block has both id and caption attributes, it will be treated as numbered code block.

```{#lst:code .haskell caption="Listing caption"}
main :: IO ()
main = putStrLn "Hello World!"

Table-style captions

Enabled with codeBlockCaptions metadata option. If code block is immediately adjacent to paragraph, starting with Listing: or : , said paragraph will be treated as code block caption.

Listing: Listing caption

```{#lst:code .haskell}
main :: IO ()
main = putStrLn "Hello World!"


```{#lst:code .haskell}
main :: IO ()
main = putStrLn "Hello World!"

: Listing caption

Wrapping div

Wrapping code block without label in a div with id lst:... and class, starting with listing, and adding paragraph before code block, but inside div, will treat said paragraph as code block caption.

<div id="lst:code" class="listing">
Listing caption
main :: IO ()
main = putStrLn "Hello World!"


[@fig:label1;@fig:label2;...] or [@eq:label1;@eq:label2;...] or [@tbl:label1;@tbl:label2;...] or @fig:label or @eq:label or @tbl:label

Reference syntax heavily relies on citation syntax. Basic reference is created by writing @, then basically desired label with prefix. It is also possible to reference a group of objects, by putting them into brackets with ; as separator. Similar objects will be grouped in order of them appearing in citation brackets, and sequential reference numbers will be shortened, e.g. 1,2,3 will be shortened to 1-3.

You can capitalize first reference character to get capitalized prefix, e.g. [@Fig:label1] will produce Fig. ... by default. Capitalized prefixes are derived automatically by capitalizing first letter of every word in non-capitalized prefix, unless overriden with metadata settings. See Customization for more information.


It's possible to use raw latex commands \listoffigures, \listoftables and listoflistings, which will produce ordered list of figure/table/listings titles, in order of appearance in document.

\listoflistings depends on other options, and is defined in preamble, so it will work reliably only with standalone/pdf output.


Assuming you already installed Haskell platform, you can install pandoc-crossref with cabal:

cabal update
cabal install pandoc-crossref


Run pandoc with --filter option, passing path to pandoc-crossref executable, or simply pandoc-crossref, if it's in PATH:

pandoc --filter pandoc-crossref

If you installed with cabal, it's most likely located in $HOME/.cabal/bin on *NIX systems, or in %AppData%\cabal\bin on Windows.


There are several parameters that can be set via YAML metadata (either by passing -M to pandoc, or by setting it in source markdown)

Following variables are supported:

  • cref: if True, latex export will use \cref from cleveref package. Only relevant for LaTeX output. \usepackage{cleveref} will be automatically added to header-includes.
  • chapters: if True, number elements as chapter.item, and restart item on each first-level heading (as --chapters for latex/pdf output)
  • chaptersDepth, default 1: header level to treat as "chapter". If chaptersDepth>1, then items will be prefixed with several numbers, corresponding to header numbers, e.g. fig. 1.4.3.
  • listings: if True, generate code blocks for listings package. Only relevant for LaTeX output. \usepackage{listings} will be automatically added to header-includes. You need to specify --listings option as well.
  • codeBlockCaptions: if True, parse table-style code block captions.
  • figureTitle, default Figure: Word(s) to prepend to figure titles, e.g. Figure 1: Description
  • tableTitle, default Table: Word(s) to prepend to table titles, e.g. Table 1: Description
  • listingTitle, default Listing: Word(s) to prepend to listing titles, e.g. Listing 1: Description
  • titleDelimiter, default :: What to put between object number and caption text.
  • figPrefix, default fig., figs.: Prefix for references to figures, e.g. figs. 1-3
  • eqnPrefix, default eq., eqns.: Prefix for references to equations, e.g. eqns. 3,4
  • tblPrefix, default tbl., tbls.: Prefix for references to tables, e.g. tbl. 2
  • lstPrefix, default lst., lsts.: Prefix for references to lists, e.g. lsts. 2,5
  • secPrefix, default sec., secs.: Prefix for references to sections, e.g. secs. 2,5
  • autoSectionLabels, default false: Automatically prefix all section labels with sec:. Note that this messes with pandoc's automatic header references.
  • chapDelim, default .: Delimiter between chapter number and item number.
  • rangeDelim, default -: Delimiter between reference ranges, e.g. eq. 2-5
  • lofTitle, default # List of Figures: Title for list of figures (lof)
  • lotTitle, default # List of Tables: Title for list of tables (lot)
  • lolTitle, default # List of Listings: Title for list of listings (lol)
  • figureTemplate, default \\[figureTitle\\] \\[i\\]\\[titleDelim\\] \\[t\\]: template for figure captions, see Templates
  • tableTemplate, default \\[tableTitle\\] \\[i\\]\\[titleDelim\\] \\[t\\]: template for table captions, see Templates
  • listingTemplate, default \\[tableTitle\\] \\[i\\]\\[titleDelim\\] \\[t\\]: template for listing captions, see Templates

figPrefix, eqnPrefix, tblPrefix, lstPrefix can be YAML arrays. That way, value at index corresponds to total number of references in group, f.ex.

  - "fig."
  - "figs."

Will result in all single-value references prefixed with "fig.", and all reference groups of two and more prefixed with "figs.":

[@fig:one] -> fig. 1
[@fig:one; @fig:two] -> figs. 1, 2
[@fig:one; @fig:two; @fig:three] -> figs. 1-3

They can be YAML strings as well. In that case, prefix would be the same regardless of number of references.

They can also be used with first character capitalized, i.e. FigPrefix, etc. In this case, these settings will override default reference capitailzation settings.

LaTeX customization

Support for above variables with LaTeX/PDF output is limited. In particular, the following variables are honored:

  • figureTitle
  • tableTitle
  • listingTitle
  • lofTitle -- ignores formatting
  • lotTitle -- ignores formatting
  • lolTitle -- ignores formatting
  • *Prefix, upper-/lowercase and single/plural form. Note that with cleveref output, if *Prefix is array, only first two items are used, and the rest is ignored.

Templates are not supported.

You can add arbitrary LaTeX commands to document header, however, using header-includes metadata field. Please bear in mind, that pandoc-crossref up to and including requires header-includes to be YAML array, e.g.

    - "\\newcommand{\\pcdoc}{Pandoc-crossref documentation}"

This will be added before any customization applied by pandoc-crossref. For a complete list of what is added to template, consult ModifyMeta.hs.


pandoc-crossref supports advanced caption customization via caption templates. Templates are specified as YAML metadata variables (see Customization), and are parsed as default Pandoc Markdown. Variables are specified with display math syntax, i.e. $$var$$ in a template will be replaced with value of variable var. Variables can be specified in YAML metadata block, or from command line (with -M switch). There are two special variables, that are set internally:

  • i -- object number, possibly with chapter number (if chapter=True)
  • t -- object caption, as given in source Markdown

Please note that at the moment, templates are not supported with LaTeX/PDF output.

Settings file

It is also possible to set variables used by pandoc-crossref with a separate YAML file. If a given variable is not set in metadata, then pandoc-crossref will attempt to read it from file specified by crossrefYaml metadata variable, or, if not set, from pandoc-crossref.yaml from current working directory. This allows for reusable configurations. One possible application is ad-hoc internationalization.

For example, consider $HOME/misc/pandoc-crossref-es.yaml:

figureTitle: "Figura"
tableTitle: "Tabla"
figPrefix: "fig."
eqnPrefix: "ec."
tblPrefix: "tbl."
loftitle: "# Lista de figuras"
lotTitle: "# Lista de tablas"

One could use this with pandoc-crossref as follows:

pandoc -F pandoc-crossref.hs -M "crossrefYaml=$HOME/misc/pandoc-crossref-es.yaml"