frame_mem_utils 0.2.5

a few stack oriented utileties designed with unsafe in mind
Documentation 
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use core::marker::PhantomData;
use core::mem::ManuallyDrop;
use core::ops::Deref;
use core::ops::DerefMut;
use core::ptr::NonNull;

#[derive(Debug, PartialEq, Eq, Hash)]
pub struct RefBox<'a, T: ?Sized> {
    ptr: NonNull<T>,
    _ph: PhantomData<&'a mut T>,
}

unsafe impl<T> Send for RefBox<'_, T> where T: Send {}
unsafe impl<T> Sync for RefBox<'_, T> where T: Sync {}

impl<'a, T: ?Sized> RefBox<'a, T> {
    pub unsafe fn new(t: &'a mut T) -> Self {
        Self {
            ptr: t.into(),
            _ph: PhantomData,
        }
    }

    pub unsafe fn drop_this(t: &'a mut ManuallyDrop<T>) -> Self {
        Self {
            ptr: unsafe { &mut *(t as *mut ManuallyDrop<T> as *mut T) }.into(),
            _ph: PhantomData,
        }
    }

    pub fn leak(self) -> &'a mut T {
        let ans = unsafe { &mut *self.ptr.as_ptr() };
        core::mem::forget(self);
        ans
    }

    pub fn into_inner(self) -> T
    where
        T: Sized,
    {
        let ans = unsafe { self.ptr.as_ptr().read() };
        core::mem::forget(self);
        ans
    }
}

impl<T: ?Sized> Drop for RefBox<'_, T> {
    fn drop(&mut self) {
        unsafe { core::ptr::drop_in_place(self.ptr.as_ptr()) }
    }
}

impl<T: ?Sized> Deref for RefBox<'_, T> {
    type Target = T;
    fn deref(&self) -> &T {
        unsafe { &*self.ptr.as_ptr() }
    }
}
impl<T: ?Sized> DerefMut for RefBox<'_, T> {
    fn deref_mut(&mut self) -> &mut T {
        unsafe { &mut *self.ptr.as_ptr() }
    }
}