Struct EventHandlerRegistry 

pub struct EventHandlerRegistry { /* private fields */ }

Registry for maintaining event handlers.

Example

impl Host for MyHost {
    fn on_event(
        &mut self,
        process: &mut ProcessState,
        event_id: u32,
    ) -> Result<(), EventError> {
        if self
            .event_handlers
            .handle_event(event_id, process)
            .map_err(|err| EventError::HandlerError { id: event_id, err })?
        {
            // the event was handled by the registered event handlers; just return
            return Ok(());
        }

        // implement custom event handling

        Err(EventError::UnhandledEvent { id: event_id })
    }
}

Implementations

impl EventHandlerRegistry

pub fn new() -> Self

pub fn register( &mut self, id: u32, handler: Box<dyn EventHandler>, ) -> Result<(), ExecutionError>

Registers a boxed EventHandler with a given identifier.

pub fn unregister(&mut self, id: u32) -> bool

Unregisters a handler with the given identifier, returning a flag whether a handler with that identifier was previously registered.

pub fn handle_event( &self, id: u32, process: &ProcessState<'_>, ) -> Result<Option<Vec<AdviceMutation>>, EventError>

Handles the event if the registry contains a handler with the same identifier.

Returns an Option<_> indicating whether the event was handled, wrapping resulting mutations if any. Returns None if the event was not handled, if the event was handled successfully Some(mutations) is returned, and if the handler returns an error, it is propagated to the caller.

Trait Implementations

impl Debug for EventHandlerRegistry

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

Formats the value using the given formatter.

impl Default for EventHandlerRegistry

fn default() -> EventHandlerRegistry

Returns the “default value” for a type.