33 lines
787 B
Rust
33 lines
787 B
Rust
// Copyright 2018 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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#![feature(decl_macro)]
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macro modern($a: ident) {
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struct Modern {
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a: u8,
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$a: u8, // OK
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}
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}
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macro_rules! legacy {
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($a: ident) => {
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struct Legacy {
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a: u8,
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$a: u8, //~ ERROR field `a` is already declared
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}
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}
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}
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modern!(a);
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legacy!(a);
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fn main() {}
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