Re: How to access Span elements with lua filter based on their content

[Albert Krewinkel <albert+pandoc-9EawChwDxG8hFhg+JK9F0w@public.gmane.org>]

krulis....-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org writes:

> I am using pandoc to convert `org-agenda` list of todos to `docx` and `pdf`
> for my coworkers. File exported from `emacs org-agenda` can look like that
> (simplified):
>
> `tasks.org`
> ```
> * TODO Feed the cat
> ```
>
> Pandoc native output of this file parsing is:
>
> ```
> [Header 1 ("feed-the-cat",[],[]) [Span ("",["todo","TODO"],[]) [Str
> "TODO"],Space,Str "Feed",Space,Str "the",Space,Str "cat"]]
> ```
>
> Now if I convert this to any output format, I get spurious "TODO" pandoc
> strings (that are present from `org-mode`). How can I get rid of this
> "TODO" string (preferably also with surrounding spaces)?

Two options:

1. The org reader recognizes most org export options. So adding the
   following line to your input file should be enough:

       #+OPTIONS: todo:nil

   See: https://orgmode.org/manual/Export-Settings.html

2. With a Lua filter you'll want

      function Span (span)
        if span.classes:includes 'todo' then
          return {}   -- delete this element
        end
      end

> So, how can I access, or match, `pandoc Span` elements based on their
> content? Where can I read more about this?

_Just_ on their content is difficult for various reasons, but you can
compare AST elements using the normal `==` Lua operator. The comparison
of elements happens in Haskell, where elements don't have identity.

So `pandoc.Span {pandoc.Str 'hi'} == pandoc.Span {pandoc.Str 'hi'}`
would be true, but `{pandoc.Str 'hi'} == {pandoc.Str 'hi'}` would be
false, as lists are note treated as AST elements. We might change that
at some point.

HTH,

--
Albert Krewinkel
GPG: 8eed e3e2 e8c5 6f18 81fe  e836 388d c0b2 1f63 1124