Is there a way to use h1 as title: in metadata if title: isn't specified?

[the-solipsist]

I've got 50+ qmd files with # title, and that same string copied in the metadata with title:.

When I render the files as html, the title gets duplicated, with 2 <h1> headings.

If I remove title:, then the title-metadata block doesn't get rendered correctly. I've tried --shift-heading-by=-1, but that makes ## <h2> headings into # <h1> headings. I can manually remove the # heading for each of the files. But I'm wondering if there's any way to make quarto treat <h1> headings as titles.

[mcanouil]

Would you be able to share the code ? I am not fully sure to understand your case.

[the-solipsist]

I have a file like this:

---
title: "Grand Title"
author: "Pranesh Prakash"
date: 2011-01-25
standalone: true
shift-heading-level-by: 0
---

# Grand Title

Lorem. 

## Heading 2

Lorem ipsum.

The <h1> title appears twice:

---
title: "Grand Title"
author: "Pranesh Prakash"
date: 2011-01-25
standalone: true
shift-heading-level-by: -1
---

# Grand Title

Lorem. 

## Heading 2

Lorem ipsum.

If I use shift-heading-level-by: -1, then the title issue gets fixed, but "Heading 2" becomes an <h1>, which I don't want.

---
author: "Pranesh Prakash"
date: 2011-01-25
standalone: true
shift-heading-level-by: 0
---

# Grand Title

Lorem. 

## Heading 2

Lorem ipsum.

If I remove title: from the metadata and don't shift the heading levels, then the metadata block disappears:

---
title: "Grand Title"
author: "Pranesh Prakash"
date: 2011-01-25
standalone: true
shift-heading-level-by: 0
---

Lorem. 

## Heading 2

Lorem ipsum.

What I'd like is ideally this while keeping # Grand Title:

[mcanouil]

Why do you have Quarto document with h1 title and title set if you don't want that?
This is the standard behaviour of Quarto.
What you could do is write a small Lua filter to remove h1 title that do not have the title class.

[the-solipsist]

If anyone reading this wants to know how to get this done, either:

1. delete all instances of # title, or
2. Use this lua filter (adapted from @tarleb's lua filter here)

local title

-- Set title from level 1 header, or
-- discard level 1 header if title is already set.
function promote_header_title (header)

  if header.level >= 2 then
    return header
  end

  if not title then
    title = header.content
    return {}
  end

  local msg = '[WARNING] title already set; discarding header "%s"\n'
  io.stderr:write(msg:format(pandoc.utils.stringify(header)))
  return {}
end

return {
  {Meta = function (meta) title = meta.title end}, -- init title
  {Header = promote_header_title},
  {Meta = function (meta) meta.title = title; return meta end}, -- set title
}