syntax_data: {"ast_node_type":"variable","tokens":[{"end":64,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let key = (infcx.typing_env(param_env), trait_pred);
context_before:         if self.can_use_global_caches(param_env, trait_pred) {
context_after:             if let Some(res) = tcx.evaluation_cache.get(&key, tcx) {