syntax_data: {"ast_node_type":"other","tokens":[{"end":83,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // a corresponding `NodeId`, since those are not yet phased out). The parent of
context_before:     // `HirId` that is located within the context where the closure appears (and, sadly,
context_after:     // the closure's `DefId` will also be the context where it appears.