syntax_data: {"ast_node_type":"variable","tokens":[{"end":90,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                     let mut sig = self.tcx().fn_sig(def_id).instantiate(self.tcx(), args);
context_before:                 } else {
context_after:                     if self.tcx().codegen_fn_attrs(def_id).safe_target_features {