Method register_higher_order_function

datafusion/execution/src/task.rs:237–248

(
        &mut self,
        function: Arc<HigherOrderUDF>,
    )

    }

    fn register_higher_order_function(
        &mut self,
        function: Arc<HigherOrderUDF>,
    ) -> Result<Option<Arc<HigherOrderUDF>>> {
        function.aliases().iter().for_each(|alias| {
            self.higher_order_functions
                .insert(alias.clone(), Arc::clone(&function));
        });
        Ok(self
            .higher_order_functions
            .insert(function.name().into(), function))
    }

    fn expr_planners(&self) -> Vec<Arc<dyn ExprPlanner>> {
        vec![]