Tell Documenter about non-`export`ed names that are part of my package's public API

[DilumAluthge]

In my package's documentation, I have a page public.md with the following contents:

# Public API

```@autodocs
Modules = [MyPackage]
Public = true
Private = false
```

And a page private.md with the following contents:

# Private API (Internals)

```@autodocs
Modules = [MyPackage]
Public = false
Private = true
```

Obviously, all of the exported names in my package are part of the public API. However, the converse is false. There are some names in my package that part of the public API but are not exported.

Unfortunately, currently, these names will show up on the private.md page, and they will not show up on the public.md page.

Is there a way to tell Documenter that certain non-exported names are actually part of the public API, so that they do show up under the public names and do not show up under the private names?

[mortenpi]

Just thinking out loud here a bit:

• Now that we have the public keyword (Add public keyword JuliaLang/julia#50105), this should be based on that.
• I also think that there are two slightly separate actionable things here:
  1. Adding support for using the public declarations for filtering in the at-autodocs.
  2. Adding an indicator to the spliced docstrings. My two cents right now is that we should add a badge (or something) for internal docstrings, and just keep rendering the public ones like we do right now (I expect most docstrings that get included in the manual to be public API).

[mortenpi]

Third action item here:

3. Add a checkdocs = :public option, to make sure that all docstrings that are considered public API are included in the manual. Current options are :none (no checks), :exports (only checks exported names, but not non-exported public names), and :all (would include also non-public internal docstrings).

[LilithHafner]

Adding an indicator to the spliced docstrings. My two cents right now is that we should add a badge (or something) for internal docstrings, and just keep rendering the public ones like we do right now (I expect most docstrings that get included in the manual to be public API).

Agreed. This is also what the REPL help mode does.

[gdalle]

Bumping this issue, since it would be very useful especially to mark non-public docstrings with a scary badge. But listing the public ones as part of @autodocs would be great too. How hard would it be for someone who has never contributed to Documenter?