pandoc codeblock containing Unicode characters

Question

Motivation
In Julia, many Unicode characters are allowed as identifier.  This facilitates the reading of algorithms containing greek letters like α, λ, ετc.

Question
How to fix the following Markdown codeblock so that pandoc can compile it to PDF?
```julia
? = 2
```

Minimal example test.md.
Error received
$ pandoc --pdf-engine=xelatex test.md -o test.pdf
[WARNING] Missing character: There is no ? in font [lmmono10-regular]:!

I tried
---
mainfont: Liberation Serif
---

```julia
? = 2
```

but I'm getting the same error.

(Edited)
My TeX Live 2020 :

I've tried mixing normal text with emojis and compile with LuaLaTeX, but only emojis were shown when the main font is set to Noto Emoji Color.

(Edit)  Thanks to comment, I've managed to get LuaLaTeX working with
documentclass{minimal}
usepackage{fontspec}
directlua
{luaotfload.add_fallback
 ("myfallback",
  {
   "NotoColorEmoji:mode=harf;"
  }
 )
}
setmainfont{LatinModernRoman}[
 RawFeature={fallback=myfallback}
]
begin{document}
It ? lorem ? LaTeX.
end{document}

My new try:
---
header-includes: |
  directlua
  {luaotfload.add_fallback
   ("myfallback",
    {
     "NotoColorEmoji:mode=harf;"
    }
   )
  }
mainfont: LatinModernRoman
mainfontoptions:
- RawFeature={fallback=myfallback}
---

It ? lorem ? LaTeX.

Error received:
$ pandoc --pdf-engine=lualatex test.md -o test.pdf
Error producing PDF.
! Undefined control sequence.
<argument> LaTeX3 error: 
                Misplaced equals sign in key-value input on line 17
l.17 fi

David Purton · Accepted Answer

You are getting the errors because pandoc treats the header as Markdown. You need to tell it to treat your header as a LaTeX code block.
However even after doing this, it still fails because the template puts the font selection before it inserts the header material. So you need to put the font selection in your header for things to happen in the right order.
You can use:
pandoc -s test.md -o test.tex

to see the intermediate tex file and diagnose what is going wrong.
Putting it all together, this will work:
---
header-includes:
- |
  ```{=latex}
  directlua{luaotfload.add_fallback(
               "myfallback",
               {"NotoColorEmoji:mode=harf;"}
             )}
  setmainfont[RawFeature={fallback=myfallback}]{LatinModernRoman}
  setmonofont[RawFeature={fallback=myfallback}]{LatinModernMono}
  ```
---

It ? lorem ? LaTeX.

```julia
? = 2
```

And then run:
pandoc --pdf-engine=lualatex test.md -o test.pdf

which gives:

pandoc codeblock containing Unicode characters

Motivation

Question

Error received

One Answer

Add your own answers!

Ask a Question