syntax_data: {"ast_node_type":"variable","tokens":[{"end":68,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let fn_sig = tcx.fn_sig(did).instantiate(tcx, args);
context_before:                 // more general issue however.
context_after:                 fn_sig.output().skip_binder().visit_with(self);