Expand description
§EmptyBox
, a way to safely move values in and out of Box
s without
reallocations
EmptyBox
is similar to a statically checked Box<Option<T>>
:
use empty_box::EmptyBox;
// A box with a string!
let boxed = Box::new("Hello!".to_string());
// Oh no, we don't like that string.
let (string, empty) = EmptyBox::take(boxed);
// Let's make an objectively superior string, and put it into the original
// box.
let superior = "Objectively superior string!".to_string();
// Now we have our superior string in the box!
let boxed = empty.put(superior);
assert_eq!("Hello!", string);
assert_eq!("Objectively superior string!", &*boxed);
Creating an EmptyBox
from a Box
and then putting a T
back into the
EmptyBox
will avoid allocating a new Box
, instead reusing whatever old
Box
the T
was EmptyBox::take
n from.
Structs§
- An “emptied”
Box
. Constructed viaEmptyBox::take()
, anEmptyBox<T>
is aBox
from which the contents have been moved. This allows for reuse of theBox
viaEmptyBox::put()
, which moves the contents back in, turning theEmptyBox
back into aBox<T>
.