* Executes compilation and passes the {@code Alert}s generated by
* compile to the {@link AlertSink}
*/
public void call(AlertSink alertSink) {
// Make sure that any given alert is only sent to the sink once
alertSink = new UniquifyingAlertSink(alertSink);
// build up a schema factory
SchemaFactory schemaFactory = new DelegatingSchemaFactory(
new FileBackedSchemaFactory(alertSink, schemaFiles),
new BuiltinSchemaFactory(alertSink));