There's not really any reason to not have the visibility default to
inherited, and this saves us the trouble of checking everywhere for
whether we have a visibility or not.
This means that callers can pass in a closure like
`|buf| some_function(..., &mut buf)` and pass in arbitrary arguments to
that function without complicating the trait definition. We also keep
the impl for str and String, since it's useful to be able to just pass
in "" or format!("{}"...) results in some cases.
This changes Print's definition to take self, instead of &self, because
otherwise FnOnce cannot be called directly. We could instead take FnMut
or even Fn, but that seems like it'd merely complicate matters -- most
of the time, the FnOnce does not constrain us at all anyway. If it does,
a custom Print impl for &'_ SomeStruct is not all that painful.
This introduces a WithFormatter abstraction that permits one-time
fmt::Display on an arbitrary closure, created via `display_fn`. This
allows us to prevent allocation while still using functions instead of
structs, which are a bit unwieldy to thread arguments through as they
can't easily call each other (and are generally a bit opaque).
The eventual goal here is likely to move us off of the formatting
infrastructure entirely in favor of something more structured, but this
is a good step to move us in that direction as it makes, for example,
passing a context describing current state to the formatting impl much
easier.
Fix confusion in theme picker functions
To reproduce the bug currently: click on the theme picker button twice (to show it then hide it). Then click anywhere else: the dropdown menu appears again.
The problem was coming from a confusion of what the `hideThemeButtonState` and `showThemeButtonState` were supposed to do. I switched their codes and updated the `switchThemeButtonState` function. It now works as expected.
r? @kinnison
These impls prevent ergonomic use of the config (e.g., forcing us to use
RefCell) despite all usecases for these structs only using their Display
impls once.
This drops the parking_lot dependency; the ReentrantMutex type appeared
to be unused (at least, no compilation failures occurred).
This is technically a possible change in behavior of its users, as
lock() would wait on other threads releasing their guards, but since we
didn't actually remove any threading or such in this code, it appears
that we never used that behavior (the behavior change is only noticeable
if the type previously was used in two threads, in a single thread
ReentrantMutex is useless).
Fix theme picker blur handler: always hide instead of switching
Fixes a minor bug in UI generated by rustdoc.
For example, this page: https://doc.rust-lang.org/std/
Reproduction steps:
1. Click the theme picker twice
* The list of themes will be shown and then hidden
2. Click anywhere else
* The list of themes will be show again, which is unexpected
The bug was caused by blur event handler toggling the state of the element instead of always hiding it regardless of the current state.
Change opaque type syntax from `existential type` to type alias `impl Trait`
This implements a new feature gate `type_alias_impl_trait` (this is slightly different from the originally proposed feature name, but matches what has been used in discussion since), deprecating the old `existential_types` feature.
The syntax for opaque types has been changed. In addition, the "existential" terminology has been replaced with "opaque", as per previous discussion and the RFC.
This makes partial progress towards implementing https://github.com/rust-lang/rust/issues/63063.
r? @Centril
