futures_util/
macros.rs

1/// Pins a value on the stack.
2///
3/// Can safely pin values that are not `Unpin` by taking ownership.
4///
5/// **Note:** Since Rust 1.68, this macro is soft-deprecated in favor of
6/// [`pin!`](https://doc.rust-lang.org/std/pin/macro.pin.html) macro
7/// in the standard library.
8///
9/// # Example
10///
11/// ```rust
12/// # use futures_util::pin_mut;
13/// # use core::pin::Pin;
14/// # struct Foo {}
15/// let foo = Foo { /* ... */ };
16/// pin_mut!(foo);
17/// let _: Pin<&mut Foo> = foo;
18/// ```
19#[macro_export]
20macro_rules! pin_mut {
21    ($($x:ident),* $(,)?) => { $(
22        // Move the value to ensure that it is owned
23        let mut $x = $x;
24        // Shadow the original binding so that it can't be directly accessed
25        // ever again.
26        #[allow(unused_mut)]
27        let mut $x = unsafe {
28            $crate::__private::Pin::new_unchecked(&mut $x)
29        };
30    )* }
31}
futures_util/macros.rs

futures_util/
macros.rs
