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// Copyright 2016 lazy-static.rs Developers
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// http://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.
extern crate std;
use self::std::prelude::v1::*;
use self::std::sync::Once;
pub use self::std::sync::ONCE_INIT;
pub struct Lazy<T: Sync>(pub Option<T>, pub Once);
impl<T: Sync> Lazy<T> {
#[inline(always)]
pub fn get<F>(&'static mut self, f: F) -> &T
where F: FnOnce() -> T
{
{
let r = &mut self.0;
self.1.call_once(|| {
*r = Some(f());
});
}
unsafe {
match self.0 {
Some(ref x) => x,
None => std::mem::unreachable(),
}
}
}
}
unsafe impl<T: Sync> Sync for Lazy<T> {}
#[macro_export]
macro_rules! __lazy_static_create {
($NAME:ident, $T:ty) => {
static mut $NAME: $crate::lazy::Lazy<$T> = $crate::lazy::Lazy(None, $crate::lazy::ONCE_INIT);
}
}