syntax_data: {"ast_node_type":"variable","tokens":[{"end":36,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let span = tcx.def_span(def_id);
context_before: fn construct_error(tcx: TyCtxt<'_>, def_id: LocalDefId, guar: ErrorGuaranteed) -> Body<'_> {
context_after:     let hir_id = tcx.local_def_id_to_hir_id(def_id);