Method map_elements

datafusion/common/src/tree_node.rs:809–822

(
        mut self,
        f: F,
    )

    }

    fn map_elements<F: FnMut(T) -> Result<Transformed<T>>>(
        mut self,
        f: F,
    ) -> Result<Transformed<Self>> {
        // Rewrite in place so the existing heap allocation can be reused.
        // `mem::take` hands the inner `C` to `f` while leaving
        // `C::default()` in the slot, so an unwinding drop finds a valid
        // `C` even if `f` panics or the `?` short-circuits.
        let inner = std::mem::take(&mut *self);
        Ok(inner.map_elements(f)?.update_data(|c| {
            *self = c;
            self
        }))
    }
}

impl<'a, T: 'a, C: TreeNodeContainer<'a, T> + Clone + Default> TreeNodeContainer<'a, T>