pub trait ExprRegistry: Sync + Send {
// Provided methods
fn get_function(
&self,
name: &str,
payload: &[u8],
) -> Option<Arc<dyn AnonymousColumnsUdf>> { ... }
fn get_agg(
&self,
name: &str,
payload: &[u8],
) -> Result<Option<Arc<dyn AnonymousStreamingAgg>>, PolarsError> { ... }
}