Type Alias ExtensionHandler 

pub type ExtensionHandler<E, R> = Box<dyn for<'a> Fn(&'a mut E, &'a dyn ExtensionEffect<R>) -> BoxFuture<'a, Result<(), ExtensionError>> + Send + Sync>;

Handler function type for extensions

Extension handlers receive:

• &mut Endpoint: Mutable endpoint for state/communication
• &dyn ExtensionEffect: The extension to handle (must downcast)

Handlers return Result<(), ExtensionError> and must handle their extension type or return an error.

Aliased Type

pub struct ExtensionHandler<E, R>(/* private fields */);