1 /*
2 * Copyright (c) 2022 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 //! function_macro example for rust
17
18 extern crate proc_macro;
19 use proc_macro::TokenStream;
20
21 /// function make_answer
22 #[proc_macro]
make_answer(_item: TokenStream) -> TokenStream23 pub fn make_answer(_item: TokenStream) -> TokenStream {
24 "fn answer() -> u32 { 42 }".parse().unwrap()
25 }
26