syntax_data: {"ast_node_type":"variable","tokens":[{"end":34,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let def = tcx.adt_def(def_id);
context_before: pub(crate) fn adt_dtorck_constraint(tcx: TyCtxt<'_>, def_id: DefId) -> &DropckConstraint<'_> {
context_after:     let span = tcx.def_span(def_id);