Bumping this thread to note: Implementation PRs have landed in all the Swift-DocC repos' main branches:
- https://github.com/apple/swift-cmark/pull/46 (linked earlier in the thread)
- parse table cell spans in cmark and use the information by QuietMisdreavus · Pull Request #74 · apple/swift-markdown · GitHub
- Add support for row- and column-span in tables by QuietMisdreavus · Pull Request #385 · apple/swift-docc · GitHub
- https://github.com/apple/swift-docc-render/pull/420
The initial implementation opted to use the ^ marker for rowspan instead of the " marker from the proposal; the primary reason for this was to align with proposals in the CommonMark Forum discussion about table syntax. This is open to discussion; i left in the option (in swift-cmark) to use the "ditto-mark" syntax, so it would be a small change to start using it. I'd like to know what everyone thinks!