Struct LocalScope 

pub struct LocalScope { /* private fields */ }

Holds subscriptions whose callbacks run on this thread, when you pump.

Ordinary subscriptions hand their callback to the library, which may call it from the file watcher’s thread - so the callback has to be Send + Sync, which rules out Rc state and most GUI context handles. A local subscription instead queues the value and calls the callback from LocalScope::drain, on whichever thread drains.

The scope is neither Send nor Sync, so a callback registered here cannot reach another thread at all - not by convention, but because the type will not move.

Dropping the scope ends every subscription in it.

Implementations

impl LocalScope

pub fn new() -> Self

pub fn drain(&mut self)

Delivers everything queued since the last call.

Changes a callback causes while draining are picked up by the next drain, not this one, so a callback that writes what it listens to cannot spin here.

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn clear(&mut self)

pub fn changed(&self) -> Changed<'_>

Waits until something is queued.

Delivery still happens in LocalScope::drain - this only wakes the loop that calls it:

loop {
    ui.changed().await;
    ui.drain();
}

Trait Implementations

impl Default for LocalScope

fn default() -> LocalScope

Returns the “default value” for a type.