syntax_data: {"ast_node_type":"variable","tokens":[{"end":68,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:             if let Some(res) = tcx.evaluation_cache.get(&key, tcx) {
context_before:             let key = (infcx.typing_env(param_env), trait_pred);
context_after:                 Some(res)