Squashed 'third_party/rules_rust/' content from commit bf59038ca
git-subtree-dir: third_party/rules_rust
git-subtree-split: bf59038cac11798cbaef9f3bf965bad8182b97fa
Signed-off-by: Brian Silverman <bsilver16384@gmail.com>
Change-Id: I5a20e403203d670df467ea97dde9a4ac40339a8d
diff --git a/examples/proc_macro/src/lib.rs b/examples/proc_macro/src/lib.rs
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+// Copyright 2020 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// This differs from the edition 2015 version because it does not have an `extern proc_macro`
+// statement, which became optional in edition 2018.
+
+use proc_macro::TokenStream;
+
+/// This macro is a no-op; it is exceedingly simple as a result
+/// of avoiding dependencies on both the syn and quote crates.
+#[proc_macro_derive(HelloWorld)]
+pub fn hello_world(_input: TokenStream) -> TokenStream {
+ TokenStream::new()
+}