Trait zerogc::TrustedDrop

pub unsafe trait TrustedDrop: Trace { }

Indicates that a type’s Drop implementation is trusted not to resurrect any garbage collected object.

This is a requirement for a type to be allocated in GcSimpleAlloc, and also for a type to be GcSafe.

Unlike java finalizers, these trusted destructors avoids a second pass to check for resurrected objects. This is important giving the frequency of destructors when interoperating with native code.

The collector is of course free to implement support java-style finalizers in addition to supporting these “trusted” destructors.

Safety

To implement this trait, the type’s destructor must never reference garbage collected pointers that may already be dead and must never resurrect dead objects. The garbage collector may have already freed the other objects before calling this type’s drop function.

Implementations on Foreign Types

impl TrustedDrop for i8

impl TrustedDrop for i16

impl TrustedDrop for i32

impl TrustedDrop for i64

impl TrustedDrop for isize

impl TrustedDrop for u8

impl TrustedDrop for u16

impl TrustedDrop for u32

impl TrustedDrop for u64

impl TrustedDrop for usize

impl TrustedDrop for f32

impl TrustedDrop for f64

impl TrustedDrop for bool

impl TrustedDrop for char

impl TrustedDrop for &'static str

impl<T> TrustedDrop for PhantomData<T>

impl TrustedDrop for ()

impl<I> TrustedDrop for (I,) where
    I: TrustedDrop, 

impl<H, I> TrustedDrop for (H, I) where
    H: TrustedDrop,
    I: TrustedDrop, 

impl<G, H, I> TrustedDrop for (G, H, I) where
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<F, G, H, I> TrustedDrop for (F, G, H, I) where
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<E, F, G, H, I> TrustedDrop for (E, F, G, H, I) where
    E: TrustedDrop,
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<D, E, F, G, H, I> TrustedDrop for (D, E, F, G, H, I) where
    D: TrustedDrop,
    E: TrustedDrop,
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<C, D, E, F, G, H, I> TrustedDrop for (C, D, E, F, G, H, I) where
    C: TrustedDrop,
    D: TrustedDrop,
    E: TrustedDrop,
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<B, C, D, E, F, G, H, I> TrustedDrop for (B, C, D, E, F, G, H, I) where
    B: TrustedDrop,
    C: TrustedDrop,
    D: TrustedDrop,
    E: TrustedDrop,
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<A, B, C, D, E, F, G, H, I> TrustedDrop for (A, B, C, D, E, F, G, H, I) where
    A: TrustedDrop,
    B: TrustedDrop,
    C: TrustedDrop,
    D: TrustedDrop,
    E: TrustedDrop,
    F: TrustedDrop,
    G: TrustedDrop,
    H: TrustedDrop,
    I: TrustedDrop, 

impl<T, const SIZE: usize> TrustedDrop for [T; SIZE] where
    T: TrustedDrop, 

impl<'a, T: ?Sized + 'a> TrustedDrop for &'a T where
    T: TraceImmutable, 

impl<T: NullTrace> TrustedDrop for Cell<T> where
    T: TrustedDrop, 

impl<T: ImplicitWriteBarrier> TrustedDrop for RefCell<T> where
    T: TrustedDrop, 

impl<'a, T: 'a> TrustedDrop for &'a mut T where
    T: TrustedDrop, 

impl<T> TrustedDrop for [T] where
    T: TrustedDrop, 

impl<T> TrustedDrop for Option<T> where
    T: TrustedDrop, 

impl<T> TrustedDrop for Wrapping<T> where
    T: TrustedDrop, 

impl<T> TrustedDrop for Vec<T> where
    T: TrustedDrop, 

impl<T> TrustedDrop for Box<T> where
    T: TrustedDrop, 

impl<T: TraceImmutable> TrustedDrop for Rc<T> where
    T: TrustedDrop, 

impl<T: TraceImmutable> TrustedDrop for Arc<T> where
    T: TrustedDrop, 

impl TrustedDrop for String

impl<K: TraceImmutable, V, S: 'static> TrustedDrop for HashMap<K, V, S> where
    K: TrustedDrop,
    V: TrustedDrop,
    S: 'static, 

impl<T: TraceImmutable, S: 'static> TrustedDrop for HashSet<T, S> where
    T: TrustedDrop,
    S: 'static, 

Implementors

impl TrustedDrop for EpsilonCollectorId where
    Self: 'static, 

impl<'gc, Id: CollectorId> TrustedDrop for GcString<'gc, Id>

impl<'gc, T: GcSafe<'gc, EpsilonCollectorId>> TrustedDrop for EpsilonRawVec<'gc, T> where
    T: TrustedDrop, 

impl<'gc, T: GcSafe<'gc, Id>, Id: CollectorId> TrustedDrop for GcArray<'gc, T, Id> where
    T: TrustedDrop,
    Id: TrustedDrop, 

impl<'gc, T: GcSafe<'gc, Id>, Id: CollectorId> TrustedDrop for GcVecCell<'gc, T, Id> where
    T: TrustedDrop, 

impl<'gc, T: GcSafe<'gc, Id>, Id: CollectorId> TrustedDrop for Unsupported<'gc, T, Id> where
    T: TrustedDrop,
    Id: TrustedDrop, 

impl<'gc, T: GcSafe<'gc, Id>, Id: CollectorId> TrustedDrop for GcVec<'gc, T, Id> where
    T: TrustedDrop,
    Id: TrustedDrop, 

impl<'gc, T: ?Sized + GcSafe<'gc, Id>, Id: CollectorId> TrustedDrop for Gc<'gc, T, Id>

Double-indirection is completely safe

impl<T> TrustedDrop for AssumeNotTraced<T>

impl<T: Trace + Copy> TrustedDrop for GcCell<T> where
    T: TrustedDrop,