syntax_data: {"ast_node_type":"variable","tokens":[{"end":18,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let args =
context_before:         let variances = cx.variances_of(def_id.into());
context_after:             std::iter::zip(args.iter(), variances.iter()).map(|(arg, v)| match (arg.kind(), v) {