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use std::cell::{Ref, RefMut};
use std::mem::transmute;
pub unsafe fn extend_lifetime<T: ExtendableLife>(r: T) -> T::Out {
r.extend_lifetime()
}
pub unsafe trait ExtendableLife {
type Out;
unsafe fn extend_lifetime(self) -> Self::Out;
}
unsafe impl<'a, T: ?Sized + 'static> ExtendableLife for &'a T {
type Out = &'static T;
unsafe fn extend_lifetime(self) -> Self::Out {
transmute(self)
}
}
unsafe impl<'a, T: ?Sized + 'static> ExtendableLife for &'a mut T {
type Out = &'static mut T;
unsafe fn extend_lifetime(self) -> Self::Out {
transmute(self)
}
}
unsafe impl<'a, T: ExtendableLife + Sized> ExtendableLife for Option<T> {
type Out = Option<T::Out>;
unsafe fn extend_lifetime(self) -> Self::Out {
match self {
None => None,
Some(inner) => Some(inner.extend_lifetime()),
}
}
}
unsafe impl<'a, T: 'static> ExtendableLife for Ref<'a, T> {
type Out = Ref<'static, T>;
unsafe fn extend_lifetime(self) -> Self::Out {
transmute(self)
}
}
unsafe impl<'a, T: 'static> ExtendableLife for RefMut<'a, T> {
type Out = RefMut<'static, T>;
unsafe fn extend_lifetime(self) -> Self::Out {
transmute(self)
}
}