Struct Scope

pub struct Scope<T>(/* private fields */)
where
    T: ?Sized;

A scope. There’s usually one scope per thread.

Note: Usually you don’t use this directly. See thread_scoped_ref (with example) and with / scoped.

Safety

This struct uses unsafe functionality. When calling the scope function a reference to the value is kept as long as the scope function is running. The reference to the value is removed when the scope function ends. To make sure the reference is removed even in the case of a panic, there’s a cleanup struct that performs cleanup when dropped.

Implementations

impl<T> Scope<T>

where T: ?Sized,

pub fn scoped<TFn, TRet>(&self, value: &T, fun: TFn) -> TRet

where TFn: FnOnce() -> TRet,

Run the given function scoped with given value reference.

Note: Panicking within the function should be ok, the scope is cleaned up properly.

pub fn with<TFn, TRet>(&self, fun: TFn) -> TRet

where TFn: FnOnce(Option<&T>) -> TRet,

Runs the given function with the value from the scope (if there’s any). If you’re not inside a scope, there won’t be a value (function will receive None).

Trait Implementations

impl<T> Default for Scope<T>

where T: ?Sized,

Creates a new scope without value.

fn default() -> Self

Returns the “default value” for a type.