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Remove [mut] syntax in pin docs

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This commit is contained in:
Chris Gregory 2019-04-11 21:21:19 -05:00
parent 3de0106789
commit 94a5c3b2b2
1 changed files with 9 additions and 9 deletions
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18
src/libcore/pin.rs
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@ -158,12 +158,12 @@
//! is called *even if your type was previously pinned*! It is as if the
//! compiler automatically called `get_unchecked_mut`.
//!
//! This can never cause a problem in safe code because implementing a type that relies on pinning
//! requires unsafe code, but be aware that deciding to make use of pinning
//! in your type (for example by implementing some operation on `Pin<&[mut] Self>`)
//! has consequences for your `Drop` implementation as well: if an element
//! of your type could have been pinned, you must treat Drop as implicitly taking
//! `Pin<&mut Self>`.
//! This can never cause a problem in safe code because implementing a type that
//! relies on pinning requires unsafe code, but be aware that deciding to make
//! use of pinning in your type (for example by implementing some operation on
//! `Pin<&Self>` or `Pin<&mut Self>`) has consequences for your `Drop`
//! implementation as well: if an element of your type could have been pinned,
//! you must treat Drop as implicitly taking `Pin<&mut Self>`.
//!
//! In particular, if your type is `#[repr(packed)]`, the compiler will automatically
//! move fields around to be able to drop them. As a consequence, you cannot use
@ -173,13 +173,13 @@
//!
//! One interesting question arises when considering the interaction of pinning and
//! the fields of a struct. When can a struct have a "pinning projection", i.e.,
//! an operation with type `fn(Pin<&[mut] Struct>) -> Pin<&[mut] Field>`?
//! an operation with type `fn(Pin<&Struct>) -> Pin<&Field>`?
//! In a similar vein, when can a generic wrapper type (such as `Vec<T>`, `Box<T>`, or `RefCell<T>`)
//! have an operation with type `fn(Pin<&[mut] Wrapper<T>>) -> Pin<&[mut] T>`?
//! have an operation with type `fn(Pin<&Wrapper<T>>) -> Pin<&T>`?
//!
//! Having a pinning projection for some field means that pinning is "structural":
//! when the wrapper is pinned, the field must be considered pinned, too.
//! After all, the pinning projection lets us get a `Pin<&[mut] Field>`.
//! After all, the pinning projection lets us get a `Pin<&Field>`.
//!
//! However, structural pinning comes with a few extra requirements, so not all
//! wrappers can be structural and hence not all wrappers can offer pinning projections: