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// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use std::num::FromPrimitive;
use std::int;
#[deriving(Eq, FromPrimitive)]
enum A {
Foo = int::max_value,
Bar = 1,
Baz = 3,
Qux,
}
pub fn main() {
let x: Option<A> = FromPrimitive::from_int(int::max_value);
assert_eq!(x, Some(Foo));
let x: Option<A> = FromPrimitive::from_int(1);
assert_eq!(x, Some(Bar));
let x: Option<A> = FromPrimitive::from_int(3);
assert_eq!(x, Some(Baz));
let x: Option<A> = FromPrimitive::from_int(4);
assert_eq!(x, Some(Qux));
let x: Option<A> = FromPrimitive::from_int(5);
assert_eq!(x, None);
}
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