konst/
manually_drop.rs

1//! Const fn equivalents of [`ManuallyDrop<T>`](core::mem::ManuallyDrop) methods.
2
3use core::mem::ManuallyDrop;
4
5/// Const equivalent of `&*manually_drop`
6///
7/// # Example
8///
9/// ```rust
10/// use std::mem::ManuallyDrop;
11/// use konst::manually_drop;
12///
13/// const FOO: &Foo<u64> = &Foo::new(123456);
14/// const FOO_REF: &u64 = FOO.get();
15/// assert_eq!(FOO.get(), &123456);
16/// assert_eq!(FOO_REF, &123456);
17///
18/// const MD: &ManuallyDrop<u64> = &ManuallyDrop::new(654321);
19/// assert_eq!(manually_drop::as_inner(MD), &654321);
20///
21/// pub struct Foo<T>(ManuallyDrop<T>);
22///
23/// impl<T> Foo<T> {
24///     pub const fn new(value: T) -> Self {
25///         Self(ManuallyDrop::new(value))
26///     }
27///     
28///     pub const fn get(&self) -> &T {
29///         manually_drop::as_inner(&self.0)
30///     }
31/// }
32/// ```
33#[inline(always)]
34pub const fn as_inner<T>(md: &ManuallyDrop<T>) -> &T {
35    unsafe {
36        crate::utils_1_56::__priv_transmute_ref! {ManuallyDrop<T>, T, md}
37    }
38}
39
40/// Const equivalent of `&mut *manually_drop`
41///
42/// # Example
43///
44/// ```rust
45/// # #![feature(const_mut_refs)]
46/// use std::mem::ManuallyDrop;
47/// use konst::manually_drop;
48///
49/// const fn add_100(num: &mut u32 ) {
50///     *num += 100;
51/// }
52///
53/// const FOO: ManuallyDrop<u32> = {
54///     let mut mu = ManuallyDrop::new(5);
55///     let inner = manually_drop::as_inner_mut(&mut mu);
56///     add_100(inner);
57///     add_100(inner);
58///     add_100(inner);
59///     mu
60/// };
61///
62/// assert_eq!(*FOO, 305);
63/// ```
64#[cfg(feature = "mut_refs")]
65#[cfg_attr(feature = "docsrs", doc(cfg(feature = "mut_refs")))]
66#[inline(always)]
67pub const fn as_inner_mut<T>(md: &mut ManuallyDrop<T>) -> &mut T {
68    unsafe {
69        crate::utils_mut::__priv_transmute_mut! {ManuallyDrop<T>, T, md}
70    }
71}
konst/manually_drop.rs

konst/
manually_drop.rs
