You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: node.rs
    path of file: ./repos/tools/crates/rome_rowan/src/green
    
    the code of the file until where you have to start completion: use std::convert::TryFrom;
use std::fmt::Formatter;
use std::iter::Enumerate;
use std::{
    borrow::{Borrow, Cow},
    fmt,
    iter::FusedIterator,
    mem::{self, ManuallyDrop},
    ops, ptr, slice,
};

#[cfg(target_pointer_width = "64")]
use crate::utility_types::static_assert;

use countme::Count;

use crate::{
    arc::{Arc, HeaderSlice, ThinArc},
    green::{GreenElement, GreenElementRef, RawSyntaxKind},
    GreenToken, NodeOrToken, TextRange, TextSiz
    
    fn children() {
        let root = build_test_list();

        // Test that children skips missing
        assert_eq!(root.children().count(), 2);
        assert_eq!(
            root.children()
                .map(|child| child.element.to_string())
                .collect::<Vec<_>>(),
            vec!["a", "b"]
        );

        // Slot 2 (index 1) is empty
        assert_eq!(
            root.children().map(|child| child.slot).collect::<Vec<_>>(),
            vec![0, 2]
        );

        // Same when reverse
        assert_eq!(
            root.children()
                .rev()
                .map(|child| child.slot)
                .collect::<Vec<_>>(),
            vec![2, 0]
        );
    }