[rustc.git] / src / doc / edition-guide / src / rust-next / pin.md

# Pinning

![Minimum Rust version: 1.33](https://img.shields.io/badge/Minimum%20Rust%20Version-1.33-brightgreen.svg)

Rust 1.33 introduced a new concept, implemented as two types: 

* [`Pin<P>`](https://doc.rust-lang.org/std/pin/struct.Pin.html), a wrapper
  around a kind of pointer which makes that pointer "pin" its value in place,
  preventing the value referenced by that pointer from being moved.
* [`Unpin`](https://doc.rust-lang.org/std/marker/trait.Unpin.html), types that
  are safe to be moved, even if they're pinned.

Most users will not interact with pinning directly, and so we won't explain
more here. For the details, see the [documentation for
`std::pin`](https://doc.rust-lang.org/std/pin/index.html).

What *is* useful to know about pinning is that it's a pre-requisite for
`async`/`await`. Folks who write async libraries may need to learn about
pinning, but folks using them generally shouldn't need to interact with this
feature at all.
Commit	Line	Data
f035d41b XL	1	# Pinning
	2
	3	![Minimum Rust version: 1.33](https://img.shields.io/badge/Minimum%20Rust%20Version-1.33-brightgreen.svg)
	4
	5	Rust 1.33 introduced a new concept, implemented as two types:
	6
	7	* [`Pin<P>`](https://doc.rust-lang.org/std/pin/struct.Pin.html), a wrapper
	8	around a kind of pointer which makes that pointer "pin" its value in place,
	9	preventing the value referenced by that pointer from being moved.
	10	* [`Unpin`](https://doc.rust-lang.org/std/marker/trait.Unpin.html), types that
	11	are safe to be moved, even if they're pinned.
	12
	13	Most users will not interact with pinning directly, and so we won't explain
	14	more here. For the details, see the [documentation for
	15	`std::pin`](https://doc.rust-lang.org/std/pin/index.html).
	16
	17	What is useful to know about pinning is that it's a pre-requisite for
	18	`async`/`await`. Folks who write async libraries may need to learn about
	19	pinning, but folks using them generally shouldn't need to interact with this
	20	feature at all.
	21