syntax_data: {"ast_node_type":"variable","tokens":[{"end":23,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let mut collector =
context_before:     let body = tcx.hir_body_owned_by(item);
context_after:         NestedBodiesVisitor { tcx, root_def_id: item.to_def_id(), nested_bodies: vec![] };