ErrArgsNil arguments is nil.

ErrBusClosed bus was closed.

ErrHandlerNil CommandHandler or QueryHandler is nil.

ErrRegistered not register CommandHandler or QueryHandler.

ErrUnimplemented handler is not implement CommandHandler or QueryHandler.

ErrUnregistered is not register CommandHandler or QueryHandler.

NoopCommand is an CommandHandler that does nothing and returns a nil error.

NoopQuery is an QueryHandler that does nothing and returns a nil error.

Bus is a bus, register CommandHandler and QueryHandler, execute Command and query Query.

CommandHandler is a command handler that to update data.

Future represents the result of an asynchronous computation.

QueryHandler is a query handler that to handlers to read data.

The CommandHandlerFunc type is an adapter to allow the use of ordinary functions as CommandHandler.

The QueryHandlerFunc type is an adapter to allow the use of ordinary functions as QueryHandler.