27 lines
834 B
Rust
27 lines
834 B
Rust
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// Copyright 2015 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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enum Stack<T> {
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Nil,
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Cons(T, Box<Stack<T>>)
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}
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fn is_empty<T>(s: Stack<T>) -> bool {
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match s {
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Nil => true,
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//~^ WARN pattern binding `Nil` is named the same as one of the variants of the type `Stack`
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//~| HELP consider making the path in the pattern qualified: `Stack::Nil`
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_ => false
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//~^ ERROR unreachable pattern
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}
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}
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fn main() {}
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