closes#20953closes#21361
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In the future, we will likely derive these `impl`s via syntax extensions or using compiler magic (see #20617). For the time being we can use these manual `impl`s.
r? @aturon
cc @burntsushi @Kroisse
As discussed with @aturon I added implementations of various op traits for references to built-in types which was already suggested by the ops reform RFC.
The 2nd commit updates the module documentation of core::ops to fully reflect the recent change from pass-by-reference to pass-by-value and expands on the implications for generic code.
After PR #19766 added implicit coersions `*mut T -> *const T`, the explicit casts can be removed.
(The number of such casts turned out to be relatively small).
This commit aims to stabilize the `TypeId` abstraction by moving it out of the
`intrinsics` module into the `any` module of the standard library. Specifically,
* `TypeId` is now defined at `std::any::TypeId`
* `TypeId::hash` has been removed in favor of an implementation of `Hash`.
This commit also performs a final pass over the `any` module, confirming the
following:
* `Any::get_type_id` remains unstable as *usage* of the `Any` trait will likely
never require this, and the `Any` trait does not need to be implemented for
any other types. As a result, this implementation detail can remain unstable
until associated statics are implemented.
* `Any::downcast_ref` is now stable
* `Any::downcast_mut` is now stable
* `BoxAny` remains unstable. While a direct impl on `Box<Any>` is allowed today
it does not allow downcasting of trait objects like `Box<Any + Send>` (those
returned from `Thread::join`). This is covered by #18737.
* `BoxAny::downcast` is now stable.
The example of the `Index` and `IndexMut` trait contained too much `Foo`.
It now contains a bit more `Bar` to make things clearer which parts are
defining the type of the index.
I searched for times when we were hiding functions with # in the documentation,
and fixed them to not use it unless neccesary.
I also made random improvements whenever I changed something. For example,
I changed Example to Examples, for consistency.
Fixes#13423
* Not all traits are part of the prelude anymore
* We switched from pass-by-reference to pass-by-value for most traits
* Add some explanations around pass-by-value traits in the context of
generic code and additional implementations for reference types.
While it's unstable and will probably be replaced or "reformed" at some point, it's useful in the mean time to be able to introspect the type system when debugging, and not be limited to sized types.
Fixes#21058
No in-tree users. Ugly interface. Closes#14332.
I just happened to notice that this module still lives and has no users. Assuming we don't want it.
r? @aturon cc @alexcrichton
