syntax_data: {"ast_node_type":"variable","tokens":[{"end":46,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                     let ty_def_id = def.did();
context_before:                 ty::Adt(def, _args) => {
context_after:                     let ty_def_span = self.tcx.def_span(ty_def_id);