jcr writes:

> Another approach is to use Lua's debug facilities to find the path to
> the script being executed, and add its directory to the Lua package
> path. This is the function I use:
>
> ```
> local function addMyDirToPath()
> local myFile = debug.getinfo(2, "S").source:sub(2)
> local myDir = myFile:match("(.*)/.*") or '.'
> package.path = ("%s/?.lua;%s"):format(myDir, package.path)
> end
> ```

That's elegant. Another way to get the value of `myDir` would be

local myDir = pandoc.path.directory(arg[0])

and should also work on all platforms. It relies on pandoc's built-in
path library and on a feature of the default lua interpreter, which
pandoc replicates for compatibility:
https://www.lua.org/manual/5.4/manual.html#7