syntax_data: {"ast_node_type":"variable","tokens":[{"end":64,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let (value_ty, value, to_ty) = self.cast_args();
context_before:             ty::ExprKind::Cast(kind) => {
context_after:                 write!(f, "({kind:?}: ({:?}: {:?}), {:?})", value, value_ty, to_ty)