{"ast_node_type":"function","tokens":[{"end":79,"kind":"keyword","start":0,"text":"fn"}]}
    fn extend<T: IntoIterator<Item = (FileId, TextEdit)>>(&mut self, iter: T) {
impl Extend<(FileId, TextEdit)> for SourceChange {
        self.extend(iter.into_iter().map(|(file_id, edit)| (file_id, (edit, None))))