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20 lines
313 B
Rust
20 lines
313 B
Rust
// run-pass
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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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