PCell

vstd::cell::pcell_maybe_uninit

Struct PCell 

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pub struct PCell<V>(/* private fields */);
Expand description

Variant of pcell::PCell<V> for potentially uninitialized data.

See the pcell::PCell<V> docs for a high-level overview.

§Example

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use vstd::prelude::*;
use vstd::cell::pcell_maybe_uninit as un;
use vstd::raw_ptr::MemContents;

verus! {

fn example_pcell_maybe_uninit() {
    let (cell, Tracked(mut points_to)) = un::PCell::new(5);

    assert(points_to.id() == cell.id());
    assert(points_to.mem_contents() === MemContents::Init(5));

    let x = cell.take(Tracked(&mut points_to));
    assert(x == 5);

    assert(points_to.id() == cell.id());
    assert(points_to.mem_contents() === MemContents::Uninit);

    cell.put(Tracked(&mut points_to), 17);

    assert(points_to.id() == cell.id());
    assert(points_to.mem_contents() === MemContents::Init(17));
}

} // verus!

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impl<V> PCell<V>

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pub closed spec fn id(&self) -> CellId

A unique ID for the cell.

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pub const exec fn empty() -> pt : (PCell<V>, Tracked<PointsTo<V>>)

ensures
pt.1@.id() == pt.0.id(),
pt.1@.mem_contents() === MemContents::Uninit,

Return an empty (“uninitialized”) cell.

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pub const exec fn new(v: V) -> pt : (PCell<V>, Tracked<PointsTo<V>>)

ensures
pt.1@.id() == pt.0.id(),
pt.1@.mem_contents() == MemContents::Init(v),
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pub exec fn put(&self, Tracked(perm): Tracked<&mut PointsTo<V>>, in_v: V)

requires
old(perm).id() == self.id(),
old(perm).mem_contents() === MemContents::Uninit,
ensures
perm.id() == self.id(),
perm.mem_contents() === MemContents::Init(in_v),
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pub exec fn take(&self, Tracked(perm): Tracked<&mut PointsTo<V>>) -> out_v : V

requires
self.id() === old(perm).id(),
old(perm).is_init(),
ensures
perm.id() === old(perm).id(),
perm.mem_contents() === MemContents::Uninit,
out_v === old(perm).value(),
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pub exec fn replace(&self, Tracked(perm): Tracked<&mut PointsTo<V>>, in_v: V) -> out_v : V

requires
self.id() === old(perm).id(),
old(perm).is_init(),
ensures
perm.id() === old(perm).id(),
perm.mem_contents() === MemContents::Init(in_v),
out_v === old(perm).value(),
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pub exec fn borrow<'a>(&'a self, Tracked(perm): Tracked<&'a PointsTo<V>>) -> v : &'a V

requires
self.id() === perm.id(),
perm.is_init(),
ensures
*v === perm.value(),
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pub exec fn into_inner(self, Tracked(perm): Tracked<PointsTo<V>>) -> v : V

requires
self.id() === perm.id(),
perm.is_init(),
ensures
v === perm.value(),
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pub exec fn write(&self, Tracked(perm): Tracked<&mut PointsTo<V>>, in_v: V)

requires
self.id() === old(perm).id(),
ensures
perm.id() === old(perm).id(),
perm.mem_contents() === MemContents::Init(in_v),
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pub exec fn read(&self, Tracked(perm): Tracked<&PointsTo<V>>) -> out_v : V
where V: Copy,

requires
self.id() === perm.id(),
perm.is_init(),

Auto Trait Implementations§

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impl<V> !Freeze for PCell<V>

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impl<V> !RefUnwindSafe for PCell<V>

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impl<V> Send for PCell<V>

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impl<V> Sync for PCell<V>

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impl<V> Unpin for PCell<V>
where V: Unpin,

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impl<V> UnwindSafe for PCell<V>
where V: UnwindSafe,

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, VERUS_SPEC__A> FromSpec<T> for VERUS_SPEC__A
where VERUS_SPEC__A: From<T>,

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exec fn obeys_from_spec() -> bool

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exec fn from_spec(v: T) -> VERUS_SPEC__A

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T, VERUS_SPEC__A> IntoSpec<T> for VERUS_SPEC__A
where VERUS_SPEC__A: Into<T>,

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exec fn obeys_into_spec() -> bool

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exec fn into_spec(self) -> T

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impl<T, U> IntoSpecImpl<U> for T
where U: From<T>,

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open spec fn obeys_into_spec() -> bool

{ <U as FromSpec<Self>>::obeys_from_spec() }
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open spec fn into_spec(self) -> U

{ U::from_spec(self) }
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, VERUS_SPEC__A> TryFromSpec<T> for VERUS_SPEC__A
where VERUS_SPEC__A: TryFrom<T>,

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exec fn obeys_try_from_spec() -> bool

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exec fn try_from_spec( v: T, ) -> Result<VERUS_SPEC__A, <VERUS_SPEC__A as TryFrom<T>>::Error>

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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<T, VERUS_SPEC__A> TryIntoSpec<T> for VERUS_SPEC__A
where VERUS_SPEC__A: TryInto<T>,

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exec fn obeys_try_into_spec() -> bool

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exec fn try_into_spec(self) -> Result<T, <VERUS_SPEC__A as TryInto<T>>::Error>

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impl<T, U> TryIntoSpecImpl<U> for T
where U: TryFrom<T>,

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open spec fn obeys_try_into_spec() -> bool

{ <U as TryFromSpec<Self>>::obeys_try_from_spec() }
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open spec fn try_into_spec(self) -> Result<U, <U as TryFrom<T>>::Error>

{ <U as TryFromSpec<Self>>::try_from_spec(self) }