Struct clear_on_drop::ClearOnDrop
source · [−]Expand description
Zeroizes a storage location when dropped.
This struct contains a reference to a memory location, either as a
mutable borrow (&mut T
), or as a owned container (Box<T>
or
similar). When this struct is dropped, the referenced location is
overwritten with its Default
value.
Example
#[derive(Default)]
struct MyData {
value: u32,
}
let mut place = MyData { value: 0 };
{
let mut key = ClearOnDrop::new(&mut place);
key.value = 0x01234567;
// ...
} // key is dropped here
assert_eq!(place.value, 0);
Implementations
sourceimpl<P> ClearOnDrop<P> where
P: DerefMut,
P::Target: Clear,
impl<P> ClearOnDrop<P> where
P: DerefMut,
P::Target: Clear,
sourcepub fn new(place: P) -> Self
pub fn new(place: P) -> Self
Creates a new ClearOnDrop
which clears place
on drop.
The place
parameter can be a &mut T
, a Box<T>
, or other
containers which behave like Box<T>
.
Note: only the first level of dereference will be cleared. Do
not use &mut Box<T>
or similar as the place, since the heap
contents won’t be cleared in that case. If you need the place
back, use ClearOnDrop::into_place(...)
instead of a borrow.
sourcepub fn into_place(c: Self) -> P
pub fn into_place(c: Self) -> P
Consumes the ClearOnDrop
, returning the place
after clearing.
Note: this is an associated function, which means that you have
to call it as ClearOnDrop::into_place(c)
instead of
c.into_place()
. This is so that there is no conflict with a
method on the inner type.
sourcepub fn into_uncleared_place(c: Self) -> P
pub fn into_uncleared_place(c: Self) -> P
Consumes the ClearOnDrop
, returning the place
without clearing.
Note: this is an associated function, which means that you have
to call it as ClearOnDrop::into_uncleared_place(c)
instead of
c.into_uncleared_place()
. This is so that there is no conflict
with a method on the inner type.
Trait Implementations
sourceimpl<P, T: ?Sized> AsMut<T> for ClearOnDrop<P> where
P: DerefMut + AsMut<T>,
P::Target: Clear,
impl<P, T: ?Sized> AsMut<T> for ClearOnDrop<P> where
P: DerefMut + AsMut<T>,
P::Target: Clear,
sourceimpl<P, T: ?Sized> AsRef<T> for ClearOnDrop<P> where
P: DerefMut + AsRef<T>,
P::Target: Clear,
impl<P, T: ?Sized> AsRef<T> for ClearOnDrop<P> where
P: DerefMut + AsRef<T>,
P::Target: Clear,
sourceimpl<P, T: ?Sized> Borrow<T> for ClearOnDrop<P> where
P: DerefMut + Borrow<T>,
P::Target: Clear,
T: Clear,
impl<P, T: ?Sized> Borrow<T> for ClearOnDrop<P> where
P: DerefMut + Borrow<T>,
P::Target: Clear,
T: Clear,
sourceimpl<P, T: ?Sized> BorrowMut<T> for ClearOnDrop<P> where
P: DerefMut + BorrowMut<T>,
P::Target: Clear,
T: Clear,
impl<P, T: ?Sized> BorrowMut<T> for ClearOnDrop<P> where
P: DerefMut + BorrowMut<T>,
P::Target: Clear,
T: Clear,
sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<P> Ord for ClearOnDrop<P> where
P: DerefMut + Ord,
P::Target: Clear,
impl<P> Ord for ClearOnDrop<P> where
P: DerefMut + Ord,
P::Target: Clear,
sourceimpl<P, Q> PartialEq<ClearOnDrop<Q>> for ClearOnDrop<P> where
P: DerefMut + PartialEq<Q>,
P::Target: Clear,
Q: DerefMut,
Q::Target: Clear,
impl<P, Q> PartialEq<ClearOnDrop<Q>> for ClearOnDrop<P> where
P: DerefMut + PartialEq<Q>,
P::Target: Clear,
Q: DerefMut,
Q::Target: Clear,
sourcefn eq(&self, other: &ClearOnDrop<Q>) -> bool
fn eq(&self, other: &ClearOnDrop<Q>) -> bool
This method tests for self
and other
values to be equal, and is used
by ==
. Read more
sourcefn ne(&self, other: &ClearOnDrop<Q>) -> bool
fn ne(&self, other: &ClearOnDrop<Q>) -> bool
This method tests for !=
.
sourceimpl<P, Q> PartialOrd<ClearOnDrop<Q>> for ClearOnDrop<P> where
P: DerefMut + PartialOrd<Q>,
P::Target: Clear,
Q: DerefMut,
Q::Target: Clear,
impl<P, Q> PartialOrd<ClearOnDrop<Q>> for ClearOnDrop<P> where
P: DerefMut + PartialOrd<Q>,
P::Target: Clear,
Q: DerefMut,
Q::Target: Clear,
sourcefn partial_cmp(&self, other: &ClearOnDrop<Q>) -> Option<Ordering>
fn partial_cmp(&self, other: &ClearOnDrop<Q>) -> Option<Ordering>
This method returns an ordering between self
and other
values if one exists. Read more
sourcefn lt(&self, other: &ClearOnDrop<Q>) -> bool
fn lt(&self, other: &ClearOnDrop<Q>) -> bool
This method tests less than (for self
and other
) and is used by the <
operator. Read more
sourcefn le(&self, other: &ClearOnDrop<Q>) -> bool
fn le(&self, other: &ClearOnDrop<Q>) -> bool
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
sourcefn gt(&self, other: &ClearOnDrop<Q>) -> bool
fn gt(&self, other: &ClearOnDrop<Q>) -> bool
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
sourcefn ge(&self, other: &ClearOnDrop<Q>) -> bool
fn ge(&self, other: &ClearOnDrop<Q>) -> bool
This method tests greater than or equal to (for self
and other
) and is used by the >=
operator. Read more
impl<P> Eq for ClearOnDrop<P> where
P: DerefMut + Eq,
P::Target: Clear,
Auto Trait Implementations
impl<P> RefUnwindSafe for ClearOnDrop<P> where
P: RefUnwindSafe,
impl<P> Send for ClearOnDrop<P> where
P: Send,
impl<P> Sync for ClearOnDrop<P> where
P: Sync,
impl<P> Unpin for ClearOnDrop<P> where
P: Unpin,
impl<P> UnwindSafe for ClearOnDrop<P> where
P: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more