Option to integrate h3's in the outline

[thbar]

My understanding is that currently only h2 (which define sections) can appear in the outline.

It would be great, when a Livebook gets a bit long (e.g. a training we're building with @adurand-cs at the moment), to be able to add h3 to the outline.

Is it possibly something that you would allow, as an option?

[jonatanklosko]

This is a bit tricky, one way would be to parse the markdown on every change and keep track of the h3 headings, but I am not sure if it provides enough value in the general case to justify the extra bookkeeping. I briefly considered doing it on the client, but we would need to insert the outline items in the correct spots, since we also show module definitions, so that's not the best either. We probably discussed this in the past, but I don't remember :D @josevalim wdyt?

[josevalim]

I wouldn't do H3 because of the reasons you said. If we really want to go down this path, I would go a more flexible route and uncouple it from the document layout. Perhaps we could add elements with id="..." or, if we want to be more explicit, with id="..." data-livebook-section.

[jonatanklosko]

uncouple it from the document layout

What do you mean? List the defined modules separately? And build the h2/h3 outline on the client based on the data attributes in the rendered elements?

[josevalim]

That's not what I meant but, if we decide to do it based on id="..." and data-livebook-section, then that's probably the best way to implement it indeed!

[adurand-cs]

How about paging instead ? It could also be useful for long Livebooks
It doesn't fully replace the need to add h3 to the outline but it might lessen it.

[jonatanklosko]

You can use relative links between notebooks, that's the best way to split content. Each notebook has its own state, but arguably having a large notebook where further code depends on state from previous code is not desired either, because it makes it harder to manage/grasp.