pub struct Singleton<T> {
single: Option<T>,
}
#[allow(dead_code)]
impl<T> Singleton<T> {
pub const fn new(s: T) -> Self {
Singleton { single: Some(s) }
}
pub const fn empty() -> Self {
Singleton { single: None }
}
pub fn take(&mut self) -> T {
let g = core::mem::replace(&mut self.single, None);
g.unwrap()
}
}