20 lines
732 B
Rust
20 lines
732 B
Rust
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// Test that `?` macro Kleene operator can not be used when the `macro_at_most_once_rep` feature
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// gate is not used.
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macro_rules! m { ($(a)?) => {} }
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//~^ ERROR Using the `?` macro Kleene operator for "at most one" repetition is unstable
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fn main() {
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m!();
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}
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