{"ast_node_type":"other","tokens":[{"end":89,"kind":"keyword","start":0,"text":"self.parse_fn_params(|_|"}]}
            self.parse_fn_params(|_| false)?.into_iter().map(|input| input.ty).collect();
        let inputs: ThinVec<_> =
        let inputs_span = inputs_lo.to(self.prev_token.span);