Is it possible to write a custom output writer for Pandoc?
For example, suppose I want to convert a document:
pandoc -f markdown -t myCustomMarkup asdf.md
Does Pandoc have a way I can specify the conversion rules for myCustomMarkup? (e.g. I could specify that text that had the 'bold' attribute should map to <bold>text</bold>, and so on for all features/attributes that Pandoc recognises).
Can anyone point me to some documentation as to how I can implement my own?
I can't seem to find any mention of this.
(Additionally, is there a way to "plug in" a writer defined in a file without having to (say) re-compile pandoc? e.g. pandoc -f markdown -t myCustomMarkup --writerpath=path/to/my/writer asdf.md)
There's no easy way to do this with current pandoc, but the next version of pandoc will contain code that allows you to write custom writers with a bit of easy lua scripting. (The code for this is already in the master branch in http://github.com/jgm/pandoc.) You'll be able to do
pandoc -t myfunkyformat.lua myfile.md
Here's an example of what a custom writer script might look like:
https://github.com/jgm/pandoc/blob/master/data/sample.lua
You can use the code now if you compile from source:
https://github.com/jgm/pandoc/wiki/Installing-the-development-version-of-pandoc
Related
I assume that inserting a reference to a BibTex bibliography in a YAML-metadata is sufficient for the references to be produced. This is like pandoc does not print references when .bib file is in YAML, which was perhaps misunderstood and which has no accepted answer yet.
I have the example input file:
---
title: Ontologies of what?
author: auf
date: 2010-07-29
keywords: homepage
abstract: |
What are the objects ontologists talk about.
Inconsistencies become visible if one models real objects (cats) and children playthings.
bibliography: "BibTexExample.bib"
---
An example post. With a reference to [#Frank2010a] and more.
## References
I invoke the conversion to latex with :
pandoc -f markdown -t pdf postWithReference.markdown -s --verbose -o postWR.pdf -w latex
The pdf is produced, but it contains no references and the text is rendered as With a reference to [#Frank2010a] and more. demonstrating that the reference file was not used. The title and author is inserted in the pdf, thus the YAML-metadata is read. If I add the reference file on the command line, the output is correctly produce with the reference list.
What am I doing wrong? I want to avoid specifying the bibliography file (as duplication, DRY) on the command line. Is there a general switch to demand bibliography processing and leaving the selection of the bibliography file to the document YAML-metada?
In the more recent version requires --citeproc instead of --filter=pandoc-citeproc
Theo bibliography is inserted by the pandoc-citeproc filter. It will be run automatically when biblioraphy is set via the command lines, but has to be run manually in cases such as yours. Addind --filter=pandoc-citeproc will make it work as expected.
I am using pypandoc to convert a markdown file to LaTex. My markdown file has a header, for example:
# Header Text #
When pypandoc renders the file as a .tex file, this appears as:
\hypertarget{header-text}{%
\section{Header Text}\label{header-text}}
While this is a nice feature to make it easy to link back to section headers, I don't necessarily want that and would prefer in this case for pypandoc to just generate:
\section{Header Text}
Is there a pandoc setting, or a pypandoc setting, that can be used to turn off the \hypertarget{} feature? I have reviewed the documentation for pandoc and didn't see it anywhere.
I had the same need, and I am using the -auto_identifiers switch,
pandoc -r markdown-auto_identifiers -w latex test.md -o test.tex
That will remove both
\hypertarget{header-text}{%
and
\label{header-text}}
leaving only
\section{Header Text}
like you requested.
Source
There is no such switch. If you want different output, you'd either have to use a pandoc filter or, as #mb21 already noted, post-process the output.
Neither of these options is very good: using a filter to manually define header output will lose you all kinds of other pandoc features, like --top-level-division and support for unnumbered headers. Post-processing, on the other hand, tends to be brittle and difficult to get right.
Anyway, below is a panflute filter, which will replace headers with a custom command. Save it to a file and pass it to pypandoc via the filters option; this should give you the desired output.
from panflute import *
sectionTypes = ["section", "subsection", "subsubsection",
"paragraph", "subparagraph"]
def reduce_header(elem, doc):
if type(elem) == Header:
cmd = "\\%s{" % sectionTypes[elem.level - 1]
inlines = [RawInline(cmd, "tex")]
inlines.extend(elem.content)
inlines.append(RawInline("}", "tex"))
return Plain(*inlines)
if __name__ == "__main__":
run_filter(reduce_header)
Pandoc allows you to include metadata at the beginning of a Markdown document using a header like
---
title: The Song That Never Ends
subtitle: It Goes On and On My Friends
author: Abraham Lincoln
lang: en_US
---
Is there any way to convey this information to Pandoc when the input format is not Markdown? I’m specifically interested in HTML input. I tried calling Pandoc with --from=html+yaml_metadata_block, but this didn’t seem to change the behavior at all—the YAML block is just interpreted as HTML.
(It is possible to include some metadata in the “percent format” shown in the “pandoc_title_block” section of the manual, but there doesn’t seem to be a way to give a separate title and subtitle with that syntax. It’s also possible to include the YAML header before the HTML and to force Pandoc to interpret the input as Markdown, but this seems hacky, and if you try to convert that to “real” Markdown then the output is full of HTML tags instead of Markdown formatting characters.)
You can use the --metadata (short -M) or --metadata-file options to supply metadata on the command line, for example:
pandoc -M title="The Song That Never Ends"
A simple solution would be to use Lua filters to augment the metadata read from the HTML file as described in the Lua filters doc. Below is an updated version:
-- file: additional-metadata.lua
function read_file_as_markdown_yaml (filename)
-- read metadata file into string
local metafile = io.open(filename, 'r')
local content = metafile:read('*a')
metafile:close()
-- get metadata
return pandoc.read(content, 'markdown').meta
end
function Meta (meta)
-- read YAML file and add its content to the metadata
local yaml_meta = read_file_as_markdown_yaml(meta.default_meta_file)
for k, v in pairs(yaml_meta) do
-- use YAML metadata as fallback
meta[k] = meta[k] or v
end
return meta
end
Use with
pandoc --lua-filter additional-metadata.lua \
--metadata default_meta_file:YOUR-FILE-HERE.yaml \
your-input-file.html
Background
Pandoc's markdown lets you specify extensions for how you would like your markdown to be handled:
Markdown syntax extensions can be individually enabled or disabled by appending +EXTENSION or -EXTENSION to the format name. So, for example, markdown_strict+footnotes+definition_lists is strict markdown with footnotes and definition lists enabled, and markdown-pipe_tables+hard_line_breaks is pandoc’s markdown without pipe tables and with hard line breaks.
My specific question
For a given pandoc conversion where, say, I use grid tables in my source:
pandoc myReport.md --from markdown+pipe_tables --to latex -o myReport.pdf
How can I write a pandoc YAML block to accomplish the same thing (specifying that my source contains grid tables?)
A generalized form of my question
How can I turn extensions on and off using pandoc YAML?
Stack Overflow Questions that I don't think completely answer my question
Can I set command line arguments using the YAML metadata - This one deals with how to specify output options, but I'm trying to tell pandoc about the structure of my input
What can I control with YAML header options in pandoc? - Answerers mention pandoc's templates, but neither the latex output template nor the markdown template indicate any sort of option for grid_tables. So, it's not clear to me from these answers how knowing about the templates will help me figure out how to structure my YAML.
There may also not be a way to do this
It's always possible that pandoc isn't designed to let you specify those extensions in the YAML. Although, I'm hoping it is.
You can use Markdown Variants to do this in an Rmarkdown document. Essentially, you enter your extensions into a variant option in the YAML header block at the start of the your .Rmd file.
For example, to use grid tables, you have something like this in your YAML header block:
---
title: "Habits"
author: John Doe
date: March 22, 2005
output: md_document
variant: markdown+grid_tables
---
Then you can compile to a PDF directly in pandoc by typing in your command line something like:
pandoc yourfile.md -o yourfile.pdf
For more information on markdown variants in RStudio: http://rmarkdown.rstudio.com/markdown_document_format.html#markdown_variants
For more information on Pandoc extensions in markdown/Rmarkdown in RStudio:
http://rmarkdown.rstudio.com/authoring_pandoc_markdown.html#pandoc_markdown
You can specify pandoc markdown extension in the yaml header using md_extension argument included in each output format.
---
title: "Your title"
output:
pdf_document:
md_extensions: +grid_tables
---
This will activate the extension. See Rmarkdown Definitive Guide for details.
Outside Rmarkdown scope, you can use Pandocomatic to it, or Paru for Ruby.
---
title: My first pandocomatic-converted document
pandocomatic_:
pandoc:
from: markdown+footnotes
to: html
...
As Merchako noted, the accepted answer is specific to rmarkdown. In, for instance, Atom md_extensions: does not work.
A more general approach would be to put the extensions in the command line options. This example works fine:
----
title: "Word document with emojis"
author: me
date: June 9, 2021
output:
word_document:
pandoc_args: ["--standalone", "--from=markdown+emoji"]
----
For people stumbling across this in or after 2021, this can be done without Rmarkdown. You can specify a YAML "defaults" file, which basically includes anything you could want to configure.
In order to do what OP wanted, all you'd need to do is
from: markdown+pipe_tables
in the defaults file, then pass it when you compile.
You can also specify the input and output files, so you can end up with the very minimal command
pandoc --defaults=defaults.yaml
and have it handle the rest for you. See https://pandoc.org/MANUAL.html#extensions for more.
I want to write an asciidoc document and convert it into a pdf document. However, I want to use a format style different than the default ones. To do so I convert the txt file to docbook using asciidoc and then try to convert the resulting docbook xml to a pdf file using dblatex.
The idea is to set a particular tex style for dblatex to obtain the desired pdf result. I've copied the existing docbook.sty style as it is recommended here to do a small style modification. The only change done in the ./docbook file is \setlength{\textwidth}{18cm} to \setlength{\textwidth}{12cm}. However, when I run the command
dblatex --texstyle=./docbook.sty test.txt
Or the command
dblatex -s ./docbook.sty test.txt
Both produce the same result in the style change: none. I mean, no matter which modification I do to ./docbook.sty file, these modifications are not applied to the output. I obtain always the same result, a pdf with the default formatting. Do you guys have any idea where is the problem?
Thanks in advance.
I would recommend:
Copy the Dblatex docbook.sty to a new filename in your working directory which is "obviously yours" (e.g., mydbstyle.sty).
Continue to supply a full or relative path argument to the --texstyle option (e.g., /path/to/mydbstyle.sty or ./mydbstyle.sty). Failing to do so requires that mydbstyle.sty be in a directory enumerated by the TEXINPUTS environment variable (which you likely have not explicitly set).
Within mydbstyle.sty, use the following directives to initialize your style:
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{mydbstyle}[2013/02/15 DocBook Style]
\RequirePackageWithOptions{docbook}
% ...
% your LaTeX commands here
Pass a DocBook 4.5 XML file as an argument to Dblatex (in your example you are passing test.txt which makes me uncertain whether you're passing an AsciiDoc source file).
dblatex --texstyle=./mydbstyle.sty mybook.xml