Struct Scope

pub struct Scope<'scope, 'env: 'scope> {
    data: Arc<ScopeData>,
    scope: PhantomData<&'scope mut &'scope ()>,
    env: PhantomData<&'env mut &'env ()>,
}

A scope to spawn scoped threads in.

See scope for details.

Fields

data: Arc<ScopeData>

scope: PhantomData<&'scope mut &'scope ()>

Invariance over ’scope, to make sure ’scope cannot shrink, which is necessary for soundness.

Without invariance, this would compile fine but be unsound:

std::thread::scope(|s| {
    s.spawn(|| {
        let a = String::from("abcd");
        s.spawn(|| println!("{a:?}")); // might run after `a` is dropped
    });
});

env: PhantomData<&'env mut &'env ()>

Implementations

impl<'scope, 'env> Scope<'scope, 'env>

pub fn spawn<F, T>(&'scope self, f: F) -> ScopedJoinHandle<'scope, T>

where F: FnOnce() -> T + Send + 'scope, T: Send + 'scope,

Spawns a new thread within a scope, returning a ScopedJoinHandle for it.

Unlike non-scoped threads, threads spawned with this function may borrow non-'static data from the outside the scope. See scope for details.

The join handle provides a join method that can be used to join the spawned thread. If the spawned thread panics, join will return an Err containing the panic payload.

If the join handle is dropped, the spawned thread will be implicitly joined at the end of the scope. In that case, if the spawned thread panics, scope will panic after all threads are joined.

This call will create a thread using default parameters of Builder. If you want to specify the stack size or the name of the thread, use Builder::spawn_scoped instead.

Panics

Panics if the OS fails to create a thread; use Builder::spawn_scoped to recover from such errors.

Trait Implementations

impl Debug for Scope<'_, '_>

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

Formats the value using the given formatter.