std::ptr::swap - Rust
Description: API documentation for the Rust `swap` fn in crate `std`.
Keywords: rust, rustlang, rust-lang, swap

# Function std::ptr::swap 1.0.0 [−] [src]

    pub unsafe fn swap<T>(x: *mut T, y: *mut T)

Swaps the values at two mutable locations of the same type, without deinitializing either.

The values pointed at by `x` and `y` may overlap, unlike `mem::swap` which is otherwise equivalent. If the values do overlap, then the overlapping region of memory from `x` will be used. This is demonstrated in the examples section below.

# Safety

This function copies the memory through the raw pointers passed to it as arguments.

Ensure that these pointers are valid before calling `swap`.

# Examples

Swapping two non-overlapping regions:

    use std::ptr;

    let mut array = [0, 1, 2, 3];

    let x = array[0..].as_mut_ptr() as *mut [u32; 2];
    let y = array[2..].as_mut_ptr() as *mut [u32; 2];

    unsafe {
        ptr::swap(x, y);
        assert_eq!([2, 3, 0, 1], array);
    }Run

Swapping two overlapping regions:

    use std::ptr;

    let mut array = [0, 1, 2, 3];

    let x = array[0..].as_mut_ptr() as *mut [u32; 3];
    let y = array[1..].as_mut_ptr() as *mut [u32; 3];

    unsafe {
        ptr::swap(x, y);
        assert_eq!([1, 0, 1, 2], array);
    }Run

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