syntax_data: {"ast_node_type":"variable","tokens":[{"end":57,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let span = tcx.def_ident_span(item).unwrap();
context_before:         DefKind::Struct | DefKind::Union | DefKind::Enum => {
context_after:             let ty = tcx.type_of(item).instantiate_identity();