Type Alias DeliveryFn 

pub type DeliveryFn = Box<dyn Fn(Config, String, String, Option<String>, String) -> Pin<Box<dyn Future<Output = Result<()>> + Send>> + Send + Sync>;

Delivery function type — takes owned values so the returned future is ’static. The fourth Option<String> is the optional thread/conversation id propagated to channels whose outbound thread_id is distinct from the recipient (webhook).

Aliased Type

pub struct DeliveryFn(/* private fields */);