syntax_data: {"ast_node_type":"other","tokens":[{"end":83,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// that node's index is returned. Otherwise, the new node's index is returned.
context_before:     /// If there is already an equivalent node in the tree, nothing is added, and
context_after:     fn add_drop(&mut self, data: DropData, next: DropIdx) -> DropIdx {