syntax_data: {"ast_node_type":"variable","tokens":[{"end":40,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let mut has_emitted = false;
context_before:         ty::Alias(ty::Opaque, ty::AliasTy { def_id: def, .. }) => {
context_after:             for &(predicate, _) in tcx.explicit_item_bounds(def).skip_binder() {