30 lines
765 B
Rust
30 lines
765 B
Rust
// Copyright 2014 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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#[deriving(Clone)]
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enum Noun
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{
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Atom(int),
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Cell(~Noun, ~Noun)
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}
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fn fas(n: &Noun) -> Noun
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{
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match n
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{
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&Cell(~Atom(2), ~Cell(ref a, _)) => (**a).clone(),
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_ => fail!("Invalid fas pattern")
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}
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}
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pub fn main() {
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fas(&Cell(~Atom(2), ~Cell(~Atom(2), ~Atom(3))));
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}
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