Struct v8::HandleScope

pub struct HandleScope<'s, C = Context> { /* private fields */ }

A stack-allocated class that governs a number of local handles. After a handle scope has been created, all local handles will be allocated within that handle scope until either the handle scope is deleted or another handle scope is created. If there is already a handle scope and a new one is created, all allocations will take place in the new handle scope until it is deleted. After that, new handles will again be allocated in the original handle scope.

After the handle scope of a local handle has been deleted the garbage collector will no longer track the object stored in the handle and may deallocate it. The behavior of accessing a handle for which the handle scope has been deleted is undefined.

Implementations

impl<'s> HandleScope<'s>

pub fn new<P: NewHandleScope<'s>>(param: &'s mut P) -> P::NewScope

pub fn with_context<P: NewHandleScopeWithContext<'s>, H: Handle<Data = Context>>( param: &'s mut P, context: H ) -> Self

Opens a new HandleScope and enters a Context in one step. The first argument should be an Isolate or OwnedIsolate. The second argument can be any handle that refers to a Context object; usually this will be a Global<Context>.

pub fn get_current_context(&self) -> Local<'s, Context>

Returns the context of the currently running JavaScript, or the context on the top of the stack if no JavaScript is running.

pub fn get_entered_or_microtask_context(&self) -> Local<'s, Context>

Returns either the last context entered through V8’s C++ API, or the context of the currently running microtask while processing microtasks. If a context is entered while executing a microtask, that context is returned.

impl<'s> HandleScope<'s, ()>

pub fn throw_exception( &mut self, exception: Local<'_, Value> ) -> Local<'s, Value>

Schedules an exception to be thrown when returning to JavaScript. When an exception has been scheduled it is illegal to invoke any JavaScript operation; the caller must return immediately and only after the exception has been handled does it become legal to invoke JavaScript operations.

This function always returns the undefined value.

impl<'s> HandleScope<'s>

pub fn get_isolate_data_from_snapshot_once<T>( &mut self, index: usize ) -> Result<Local<'s, T>, DataError>

where T: 'static, for<'l> <Local<'l, Data> as TryInto<Local<'l, T>>>::Error: ToDataError, for<'l> Local<'l, Data>: TryInto<Local<'l, T>>,

Return data that was previously attached to the isolate snapshot via SnapshotCreator, and removes the reference to it. If called again with same index argument, this function returns DataError::NoData.

The value that was stored in the snapshot must either match or be convertible to type parameter T, otherwise DataError::BadType is returned.

pub fn get_context_data_from_snapshot_once<T>( &mut self, index: usize ) -> Result<Local<'s, T>, DataError>

where T: 'static, for<'l> <Local<'l, Data> as TryInto<Local<'l, T>>>::Error: ToDataError, for<'l> Local<'l, Data>: TryInto<Local<'l, T>>,

Return data that was previously attached to the context snapshot via SnapshotCreator, and removes the reference to it. If called again with same index argument, this function returns DataError::NoData.

The value that was stored in the snapshot must either match or be convertible to type parameter T, otherwise DataError::BadType is returned.

pub fn set_promise_hooks( &mut self, init_hook: Option<Local<'_, Function>>, before_hook: Option<Local<'_, Function>>, after_hook: Option<Local<'_, Function>>, resolve_hook: Option<Local<'_, Function>> )

pub fn set_continuation_preserved_embedder_data( &mut self, data: Local<'_, Value> )

pub fn get_continuation_preserved_embedder_data(&mut self) -> Local<'s, Value>

Trait Implementations

impl<'s, 'p, 'e> AsMut<HandleScope<'p>> for AllowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p> AsMut<HandleScope<'p>> for AllowJavascriptExecutionScope<'s, HandleScope<'p>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsMut<HandleScope<'p>> for ContextScope<'s, EscapableHandleScope<'p, 'e>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p> AsMut<HandleScope<'p>> for ContextScope<'s, HandleScope<'p>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsMut<HandleScope<'p>> for DisallowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p> AsMut<HandleScope<'p>> for DisallowJavascriptExecutionScope<'s, HandleScope<'p>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsMut<HandleScope<'p>> for TryCatch<'s, EscapableHandleScope<'p, 'e>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p> AsMut<HandleScope<'p>> for TryCatch<'s, HandleScope<'p>>

fn as_mut(&mut self) -> &mut HandleScope<'p>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsMut<HandleScope<'p, ()>> for AllowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, C> AsMut<HandleScope<'p, ()>> for AllowJavascriptExecutionScope<'s, HandleScope<'p, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsMut<HandleScope<'p, ()>> for ContextScope<'s, EscapableHandleScope<'p, 'e>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p> AsMut<HandleScope<'p, ()>> for ContextScope<'s, HandleScope<'p>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsMut<HandleScope<'p, ()>> for DisallowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, C> AsMut<HandleScope<'p, ()>> for DisallowJavascriptExecutionScope<'s, HandleScope<'p, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsMut<HandleScope<'p, ()>> for TryCatch<'s, EscapableHandleScope<'p, 'e, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, C> AsMut<HandleScope<'p, ()>> for TryCatch<'s, HandleScope<'p, C>>

fn as_mut(&mut self) -> &mut HandleScope<'p, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s> AsMut<HandleScope<'s>> for CallbackScope<'s>

fn as_mut(&mut self) -> &mut HandleScope<'s>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'e> AsMut<HandleScope<'s>> for EscapableHandleScope<'s, 'e>

fn as_mut(&mut self) -> &mut HandleScope<'s>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s> AsMut<HandleScope<'s>> for HandleScope<'s>

fn as_mut(&mut self) -> &mut HandleScope<'s>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, C> AsMut<HandleScope<'s, ()>> for CallbackScope<'s, C>

fn as_mut(&mut self) -> &mut HandleScope<'s, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'e, C> AsMut<HandleScope<'s, ()>> for EscapableHandleScope<'s, 'e, C>

fn as_mut(&mut self) -> &mut HandleScope<'s, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, C> AsMut<HandleScope<'s, ()>> for HandleScope<'s, C>

fn as_mut(&mut self) -> &mut HandleScope<'s, ()>

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, C> AsMut<Isolate> for HandleScope<'s, C>

fn as_mut(&mut self) -> &mut Isolate

Converts this type into a mutable reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsRef<HandleScope<'p>> for AllowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p> AsRef<HandleScope<'p>> for AllowJavascriptExecutionScope<'s, HandleScope<'p>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsRef<HandleScope<'p>> for ContextScope<'s, EscapableHandleScope<'p, 'e>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p> AsRef<HandleScope<'p>> for ContextScope<'s, HandleScope<'p>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsRef<HandleScope<'p>> for DisallowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p> AsRef<HandleScope<'p>> for DisallowJavascriptExecutionScope<'s, HandleScope<'p>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsRef<HandleScope<'p>> for TryCatch<'s, EscapableHandleScope<'p, 'e>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p> AsRef<HandleScope<'p>> for TryCatch<'s, HandleScope<'p>>

fn as_ref(&self) -> &HandleScope<'p>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsRef<HandleScope<'p, ()>> for AllowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, C> AsRef<HandleScope<'p, ()>> for AllowJavascriptExecutionScope<'s, HandleScope<'p, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e> AsRef<HandleScope<'p, ()>> for ContextScope<'s, EscapableHandleScope<'p, 'e>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p> AsRef<HandleScope<'p, ()>> for ContextScope<'s, HandleScope<'p>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsRef<HandleScope<'p, ()>> for DisallowJavascriptExecutionScope<'s, EscapableHandleScope<'p, 'e, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, C> AsRef<HandleScope<'p, ()>> for DisallowJavascriptExecutionScope<'s, HandleScope<'p, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, 'e, C> AsRef<HandleScope<'p, ()>> for TryCatch<'s, EscapableHandleScope<'p, 'e, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'p, C> AsRef<HandleScope<'p, ()>> for TryCatch<'s, HandleScope<'p, C>>

fn as_ref(&self) -> &HandleScope<'p, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s> AsRef<HandleScope<'s>> for CallbackScope<'s>

fn as_ref(&self) -> &HandleScope<'s>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'e> AsRef<HandleScope<'s>> for EscapableHandleScope<'s, 'e>

fn as_ref(&self) -> &HandleScope<'s>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s> AsRef<HandleScope<'s>> for HandleScope<'s>

fn as_ref(&self) -> &HandleScope<'s>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, C> AsRef<HandleScope<'s, ()>> for CallbackScope<'s, C>

fn as_ref(&self) -> &HandleScope<'s, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, 'e, C> AsRef<HandleScope<'s, ()>> for EscapableHandleScope<'s, 'e, C>

fn as_ref(&self) -> &HandleScope<'s, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, C> AsRef<HandleScope<'s, ()>> for HandleScope<'s, C>

fn as_ref(&self) -> &HandleScope<'s, ()>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, C> AsRef<Isolate> for HandleScope<'s, C>

fn as_ref(&self) -> &Isolate

Converts this type into a shared reference of the (usually inferred) input type.

impl<'s, C: Debug> Debug for HandleScope<'s, C>

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

Formats the value using the given formatter.

impl<'s> Deref for HandleScope<'s>

type Target = HandleScope<'s, ()>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'s> Deref for HandleScope<'s, ()>

type Target = Isolate

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'s> DerefMut for HandleScope<'s>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'s> DerefMut for HandleScope<'s, ()>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<'s, C> Drop for HandleScope<'s, C>

fn drop(&mut self)

Executes the destructor for this type.