pub fn register_callback(&mut self, callback: Callback) -> CallbackId {
        self.next_callback_id += 1;
        let callback_id = CallbackId::from(self.next_callback_id);
        self.callbacks.insert(callback_id, callback);
        callback_id
    }
/// Registers a callback for an outgoing call.
Registers a callback for an outgoing call.
Registers a callback for an outgoing call .
pub fn register_callback(&mut self, callback: Callback) -> CallbackId {
        self.next_callback_id += 1;
        let callback_id = CallbackId::from(self.next_callback_id);
        self.callbacks.insert(callback_id, callback);
        callback_id
    }
pub fn register_callback ( & mut self , callback : Callback ) -> CallbackId { self . next_callback_id += 1 ; let callback_id = CallbackId :: from ( self . next_callback_id ) ; self . callbacks . insert ( callback_id , callback ) ; callback_id }
Registers a callback for an outgoing call.
Registers a callback for an outgoing call .
&mut self
callback
Callback
&mut self
callback
Callback