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#![no_std]
#[cfg(doctest)]
#[macro_use]
extern crate doc_comment;
#[cfg(doctest)]
doctest!("../readme.md");
use core::cmp::{Eq, Ord, Ordering};
use core::fmt::Debug;
use core::mem::{forget, ManuallyDrop};
use core::ops::{Deref, DerefMut};
#[derive(Clone, Debug, Eq, Ord)]
pub struct WithDrop<T, F: FnOnce(T)> {
data: ManuallyDrop<(T, F)>,
}
impl<T, F: FnOnce(T)> WithDrop<T, F> {
pub fn new(inner: T, drop_fn: F) -> Self {
Self {
data: ManuallyDrop::new((inner, drop_fn)),
}
}
pub fn into_inner(mut self) -> T {
let (v, _) = unsafe { ManuallyDrop::take(&mut self.data) };
forget(self);
v
}
}
impl<T: PartialEq<T>, F1: FnOnce(T), F2: FnOnce(T)> PartialEq<WithDrop<T, F2>> for WithDrop<T, F1> {
fn eq(&self, other: &WithDrop<T, F2>) -> bool {
self.deref().eq(other.deref())
}
}
impl<T: PartialOrd<T>, F1: FnOnce(T), F2: FnOnce(T)> PartialOrd<WithDrop<T, F2>>
for WithDrop<T, F1>
{
fn partial_cmp(&self, other: &WithDrop<T, F2>) -> Option<Ordering> {
self.deref().partial_cmp(other.deref())
}
}
impl<T, F: FnOnce(T)> Drop for WithDrop<T, F> {
fn drop(&mut self) {
let (v, f) = unsafe { ManuallyDrop::take(&mut self.data) };
f(v);
}
}
impl<T, F: FnOnce(T)> Deref for WithDrop<T, F> {
type Target = T;
fn deref(&self) -> &T {
&(*self.data).0
}
}
impl<T, F: FnOnce(T)> DerefMut for WithDrop<T, F> {
fn deref_mut(&mut self) -> &mut T {
&mut (*self.data).0
}
}
pub fn with_drop<T, F: FnOnce(T)>(inner: T, drop_fn: F) -> WithDrop<T, F> {
WithDrop::new(inner, drop_fn)
}