Struct chakracore::context::Context

pub struct Context(_);

A sandboxed execution context with its own set of built-in objects and functions.

The majority of APIs require an active context.

In a browser or Node.JS environment, the task of executing promises is handled by the runtime. This is not the case with ChakraCore. To run promise chains, execute_tasks must be called at a regular interval. This is done using the ContextGuard.

Methods

impl Context

fn new(runtime: &Runtime) -> Result<Context>

Creates a new context and returns a handle to it.

fn make_current<'a>(&'a self) -> Result<ContextGuard<'a>>

Binds the context to the current scope.

unsafe fn get_current<'a>() -> Option<ContextGuard<'a>>

Returns the active context in the current thread.

This is unsafe because there should be little reason to use it in idiomatic code.

Usage patterns should utilize ContextGuard or exec_with_current instead.

This ContextGuard does not reset the current context upon destruction, in contrast to a normally allocated ContextGuard. This is merely a hollow reference.

fn exec_with<Ret, T: FnOnce(&ContextGuard) -> Ret>(
    &self,
    callback: T
) -> Result<Ret>

Binds the context to the closure's scope.

let result = context.exec_with(|guard| script::eval(guard, "1 + 1")).unwrap();

fn exec_with_current<Ret, T: FnOnce(&ContextGuard) -> Ret>(
    callback: T
) -> Option<Ret>

Executes a closure with the thread's active context.

This is a safe alternative to get_current. It will either return the closures result wrapped in Some, or None, if no context is currently active.

fn insert_user_data<T>(&self, value: T) -> Option<T> where
    T: Send + 'static, 

Set user data associated with the context.

• Only one value per type.
• The internal implementation uses AnyMap.
• Returns a previous value if applicable.
• The data will live as long as the runtime keeps the context.

fn remove_user_data<T>(&self) -> Option<T> where
    T: Send + 'static, 

Remove user data associated with the context.

fn get_user_data<T>(&self) -> Option<&T> where
    T: Send + 'static, 

Get user data associated with the context.

fn get_user_data_mut<T>(&self) -> Option<&mut T> where
    T: Send + 'static, 

Get mutable user data associated with the context.

impl Context

unsafe fn from_raw(value: JsRef) -> Context

Creates an instance from a raw pointer.

This is used for managing the lifetime of JSRT objects. They are tracked using reference counting; incrementing with from_raw, and decrementing with drop.

This is required to support items stored on the heap, since the JSRT runtime only observes the stack.

If used in conjunction with a Property or any Value, it is assumed a Context is active.

fn as_raw(&self) -> JsRef

Returns the underlying raw pointer.

Trait Implementations

impl Debug for Context

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl PartialEq for Context

fn eq(&self, __arg_0: &Context) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &Context) -> bool

This method tests for !=.

impl Clone for Context

fn clone(&self) -> Context

Duplicates a reference counted type.

The underlying pointer will be copied, and its reference count will be incremented, returned wrapped as the type.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Drop for Context

fn drop(&mut self)

Decrements the reference counter.