*[<Null safety>](https://dart.dev/null-safety)*
Node? child (String name)
Returns a child Node with name
.
If a child with name
already exists and was not deleted, this
method returns it. Otherwise, it creates a new Node.
Implementation
Node? child(String name) {
if (_writer == null) {
return Node.deleted();
}
if (_children.containsKey(name)) {
return _children[name];
}
return _children[name] = Node._(this, name, index, _writer!);
}