// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #![crate_type = "proc-macro"] #![warn(clippy::needless_pass_by_value)] extern crate proc_macro; use proc_macro::TokenStream; #[proc_macro_derive(Foo)] pub fn foo(_input: TokenStream) -> TokenStream { unimplemented!() }