This commit adds the headers for the top level documentation to
rustdoc's existing table of contents, along with associated items.
It only show two levels of headers. Going further would require the
sidebar to be wider, and that seems unnecessary (the crates that
have manually-built TOCs usually don't need deeply nested headers).
This commit makes three changes for consistency and readability:
- It shows the sibling navigation on module pages. It's weird
that it didn't work before, and is inconsistent with everything
else (even Crates have sibling navigation with other Crates).
- It hides the "In [parent]" header if it's the same as the
current crate, and if there's no other header between them.
We need to keep it on modules and types, since they have
their own header and data between them, and we don't want
to show siblings under a header implying that they're children.
- It adds a margin to deal with the headers butting directly into
the branding lockup.
This commit changes the layout to something a bit less "look at my logo!!!111"
gigantic, and makes it clearer where clicking the logo will actually take you.
It also means the crate name is persistently at the top of the sidebar, even
when in a sub-item page, and clicking that name takes you back to the root.
| | Short crate name | Long crate name |
|---------|------------------|-----------------|
| Root | ![short-root] | ![long-root]
| Subpage | ![short-subpage] | ![long-subpage]
[short-root]: https://github.com/rust-lang/rust/assets/1593513/fe2ce102-d4b8-44e6-9f7b-68636a907f56
[short-subpage]: https://github.com/rust-lang/rust/assets/1593513/29501663-56c0-4151-b7de-d2637e167125
[long-root]: https://github.com/rust-lang/rust/assets/1593513/f6a385c0-b4c5-4a9c-954b-21b38de4192f
[long-subpage]: https://github.com/rust-lang/rust/assets/1593513/97ec47b4-61bf-4ebe-b461-0d2187b8c6cahttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/image/index.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/crossbeam_channel/index.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/adler/struct.Adler32.htmlhttps://notriddle.com/rustdoc-html-demo-4/logo-lockup/crossbeam_channel/struct.Sender.html
This improves visual information density (the construct with the logo and
crate name is *shorter* than the logo on its own, because it's not
square) and navigation clarity (we can now see what clicking the Rust logo
does, specifically).
Compare this with the layout at [Phoenix's Hexdocs] (which is what this
proposal is closely based on), the old proposal on [Internals Discourse]
(which always says "Rust standard library" in the sidebar, but doesn't do the
side-by-side layout).
[Phoenix's Hexdocs]: https://hexdocs.pm/phoenix/1.7.7/overview.html
[Internals Discourse]: https://internals.rust-lang.org/t/poc-of-a-new-design-for-the-generated-rustdoc/11018
In newer versions of rustdoc, the crate name and version are always shown in
the sidebar, even in subpages. Clicking the crate name does the same thing
clicking the logo always did: return you to the crate root.
While this actually takes up less screen real estate than the old layout on
desktop, it takes up more HTML. It's also a bit more visually complex.
I could do what the Internals POC did and keep the vertically stacked layout
all the time, instead of doing a horizontal stack where possible. It would
take up more screen real estate, though.
This design is lifted almost verbatim from Hexdocs. It seems to work for them.
[`opentelemetry_process_propagator`], for example, has a long application name.
[`opentelemetry_process_propagator`]: https://hexdocs.pm/opentelemetry_process_propagator/OpentelemetryProcessPropagator.html
Has anyone written the rationale on why the Rust logo shows up on projects that
aren't the standard library? If we turned it off on non-standard crates by
default, it would line wrap crate names a lot less often.
Or maybe we should encourage crate authors to include their own logo more
often? It certainly helps give people a better sense of "place."
I'm not sure of anything that directly follows up this one. Plenty of other
changes could be made to improve the layout, like
* coming up with a less cluttered way to do disclosure (there's a lot of `[-]`
on the page)
* doing a better job of separating lateral navigation (vec::Vec links to
vec::IntoIter) and the table of contents (vec::Vec links to vec::Vec::new)
* giving readers more control of how much rustdoc hows them, and giving doc
authors more control of how much it generates
* better search that reduces the need to browse
But those are mostly orthogonal, not future possibilities unlocked by this change.
