Does the use of "consume" imply taking ownerhsip?

[aryzing]

The nomicon states that split_at_mut will consume its value. Does this mean it takes ownership of the value? If so, does it really take ownership?

[jonboh]

From the signature in https://doc.rust-lang.org/std/primitive.slice.html#method.split_at_mut, I wouldn't say that it takes ownership of the value, it consumes the slice which is a (mutable) reference and spits two mutable references. But it doesn't take ownership over the pointed to value.

You can experiment with modified verison of the code snippet that appears in the reference:

let mut v = [1, 0, 3, 0, 5, 6];
let (left, right) = v.split_at_mut(2);
assert_eq!(left, [1, 0]);
assert_eq!(right, [3, 0, 5, 6]);
left[1] = 2;
v[2] = 2; // ERROR! This would imply that you can refer to the values in the slice from two different mutable references
right[1] = 4;

So once, you have left and right as mutable references the mutable reference v is no longer usable.

[aryzing]

Thanks for clarifying.