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// Copyright 2014 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 core::nonzero::NonZero; use std::u32; #[derive(Copy, Clone, Debug, PartialEq, Eq)] pub struct NodeIndex { index: NonZero<u32>, } impl NodeIndex { pub fn new(value: usize) -> NodeIndex { assert!(value < (u32::MAX as usize)); unsafe { NodeIndex { index: NonZero::new((value as u32) + 1) } } } pub fn get(self) -> usize { (*self.index - 1) as usize } }