29 lines
768 B
Rust
29 lines
768 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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#[derive(Clone, Debug, PartialEq)]
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enum Expression {
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Dummy,
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Add(Box<Expression>),
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}
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use Expression::*;
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fn simplify(exp: Expression) -> Expression {
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match exp {
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Add(n) => *n.clone(),
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_ => Dummy
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}
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}
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fn main() {
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assert_eq!(simplify(Add(Box::new(Dummy))), Dummy);
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}
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