I would like to write in Markdown, then use either <font color="red">red text</font>
or <span style="color: red;">red text</span>
to color text, so that when the.md file is checked in say Gitlab, the font color is automatically parsed when browsing the HTML formatted version - but I also want to use the same.md file as a source for a PDF via (xe)latex.
I have seen:
... and my options seem to be:
<span>
explicitly for HTML, and \textcolor
explicitly for PDF via Latex, which forces me to keep two versions of the same markdown documentviolets are [blue]{color="blue"}
- which will definitely not be parsed by whatever Markdown-to-HTML engines used by Gitlab and suchSo, I was thinking - it must be possible, that I write <span>
or <font>
in my file (which would/should be recognized by Gitlab and such parsers), and then have a Lua filter for pandoc, that would transform these into \textcolor
, when using the.md file as a source to create PDF.
Unfortunately, I suck at Lua, and definitely do not know the internal document model of Pandoc enough, to be able to easily guess how could I get to these kinds of tags in a Markdown file. So my question is: is there an existing filter or setting in pandoc
already that does this - or lacking that, a Lua filter script that looks up such tags in a markdown document, that I could use a base for this kind of filtering?
Ok, I think I got somewhere - this is color-text-span.lua
(is a bit crappy, because the regex explicitly demands a space after the color:
colon, but hey - better than nothing):
-- https://stackoverflow.com/questions/62831191/using-span-for-font-color-in-pandoc-markdown-for-both-html-and-pdf
-- https://bookdown.org/yihui/rmarkdown-cookbook/font-color.html
-- https://ulriklyngs.com/post/2019/02/20/how-to-use-pandoc-filters-for-advanced-customisation-of-your-r-markdown-documents/
function Span (el)
if string.find(el.attributes.style, "color") then
stylestr = el.attributes.style
thecolor = string.match(stylestr, "color: (%a+);")
--print(thecolor)
if FORMAT:match 'latex' then
-- encapsulate in latex code
table.insert(
el.content, 1,
pandoc.RawInline('latex', '\\textcolor{'..thecolor..'}{')
)
table.insert(
el.content,
pandoc.RawInline('latex', '}')
)
-- returns only span content
return el.content
else
-- for other format return unchanged
return el
end
else
return el
end
end
Test file - test.md:
---
title: "Test of color-text-span.lua"
author: Bob Alice
date: July 07, 2010
geometry: margin=2cm
fontsize: 12pt
output:
pdf_document:
pandoc_args: ["--lua-filter=color-text-span.lua"]
---
Hello, <span style="color: red;">red text</span>
And hello <span style="color: green;">green text</span>
Call command:
pandoc test.md --lua-filter=color-text-span.lua --pdf-engine=xelatex -o test.pdf
Output:
(appreciate if someone can make this a comment, I have too low reputation to comment)
If you remove the space in the regex pattern you can omit the explicit space. Or even better allow for whitespaces and a non-mandatory semi colon:
Change the line thecolor = string.match(stylestr, "color: (%a+);")
to thecolor = string.match(stylestr, "color:%s*(%a+);?")
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.