cuprate_blockchain/
unsafe_sendable.rs

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1//! Wrapper type for partially-`unsafe` usage of `T: !Send`.
2
3//---------------------------------------------------------------------------------------------------- Import
4use std::{
5    borrow::Borrow,
6    ops::{Deref, DerefMut},
7};
8
9use bytemuck::TransparentWrapper;
10
11//---------------------------------------------------------------------------------------------------- Aliases
12#[derive(Copy, Clone, Debug, PartialEq, PartialOrd, Eq, Ord, Hash, TransparentWrapper)]
13#[repr(transparent)]
14/// A wrapper type that `unsafe`ly implements `Send` for any `T`.
15///
16/// This is a marker/wrapper type that allows wrapping
17/// any type `T` such that it implements `Send`.
18///
19/// This is to be used when `T` is `Send`, but only in certain
20/// situations not provable to the compiler, or is otherwise a
21/// a pain to prove and/or less efficient.
22///
23/// It is up to the users of this type to ensure their
24/// usage of `UnsafeSendable` are actually safe.
25///
26/// Notably, `heed`'s table type uses this inside `service`.
27pub(crate) struct UnsafeSendable<T>(T);
28
29#[expect(clippy::non_send_fields_in_send_ty)]
30// SAFETY: Users ensure that their usage of this type is safe.
31unsafe impl<T> Send for UnsafeSendable<T> {}
32
33impl<T> UnsafeSendable<T> {
34    /// Create a new [`UnsafeSendable`].
35    ///
36    /// # Safety
37    /// By constructing this type, you must ensure the usage
38    /// of the resulting `Self` is follows all the [`Send`] rules.
39    pub(crate) const unsafe fn new(t: T) -> Self {
40        Self(t)
41    }
42
43    /// Extract the inner `T`.
44    #[expect(dead_code)]
45    pub(crate) fn into_inner(self) -> T {
46        self.0
47    }
48}
49
50impl<T> Borrow<T> for UnsafeSendable<T> {
51    fn borrow(&self) -> &T {
52        &self.0
53    }
54}
55
56impl<T> AsRef<T> for UnsafeSendable<T> {
57    fn as_ref(&self) -> &T {
58        &self.0
59    }
60}
61
62impl<T> AsMut<T> for UnsafeSendable<T> {
63    fn as_mut(&mut self) -> &mut T {
64        &mut self.0
65    }
66}
67
68impl<T> Deref for UnsafeSendable<T> {
69    type Target = T;
70    fn deref(&self) -> &Self::Target {
71        &self.0
72    }
73}
74
75impl<T> DerefMut for UnsafeSendable<T> {
76    fn deref_mut(&mut self) -> &mut Self::Target {
77        &mut self.0
78    }
79}
80
81//---------------------------------------------------------------------------------------------------- Tests
82#[cfg(test)]
83mod test {
84    // use super::*;
85}
cuprate_blockchain/unsafe_sendable.rs

cuprate_blockchain/
unsafe_sendable.rs
