{"ast_node_type":"other","tokens":[{"end":20,"kind":"keyword","start":0,"text":"match"}]}
        match self {
    pub fn fn_sig(&self) -> Option<PolyFnSig> {
            TyKind::RigidTy(RigidTy::FnDef(def, args)) => Some(with(|cx| cx.fn_sig(*def, args))),