Struct mozjs::jsapi::js::ClassExtension

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#[repr(C)]
pub struct ClassExtension { pub objectMovedOp: Option<unsafe extern "C" fn(_: *mut JSObject, _: *mut JSObject) -> usize>, }

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§objectMovedOp: Option<unsafe extern "C" fn(_: *mut JSObject, _: *mut JSObject) -> usize>

Optional hook called when an object is moved by generational or compacting GC.

There may exist weak pointers to an object that are not traced through when the normal trace APIs are used, for example objects in the wrapper cache. This hook allows these pointers to be updated.

Note that this hook can be called before JS_NewObject() returns if a GC is triggered during construction of the object. This can happen for global objects for example.

The function should return the difference between nursery bytes used and tenured bytes used, which may be nonzero e.g. if some nursery-allocated data beyond the actual GC thing is moved into malloced memory.

This is used to compute the nursery promotion rate.

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impl Clone for ClassExtension

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fn clone(&self) -> ClassExtension

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for ClassExtension

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fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more
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impl PartialEq<ClassExtension> for ClassExtension

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fn eq(&self, other: &ClassExtension) -> bool

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl Copy for ClassExtension

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impl StructuralPartialEq for ClassExtension

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Blanket Implementations§

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impl<T> Any for Twhere 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 Twhere 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 Twhere 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, U> Into<U> for Twhere 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> ToOwned for Twhere T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for Twhere 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, U> TryInto<U> for Twhere 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.