Enclose sections

[flupe]

Enclose sections

[flupe]

I have implemented the behaviour described above on my fork. It's not particularly pretty but does the job.
Essentially, we fold over top-level blocks to find the document structure:

• If it's a heading, we check if it closes or opens new sections and render it manually¹.
• If it's something else, we render it using the already existing rendering functions, thus accounting for extensions.

This makes the assumption that document headings only appear at the uppermost level (in mmarkBlocks), which they should anyway.

Let me know if there's any interest in this thing.

Footnotes

1. We could also render headings with the existing rendering function, but currently this function automatically adds an id to every heading, which we obviously want to avoid. We could turn auto-ids into an extension, too. ↩

[mrkkrp]

I think the best thing we can do here is to expose more internals of MMark, e.g. in Text.MMark.Internal to facilitate custom logic like this. I'm open to a PR that does that.