# 1.9.0[−][src]Trait std::panic::UnwindSafe

    pub auto trait UnwindSafe { }

A marker trait which represents "panic safe" types in Rust.

This trait is implemented by default for many types and behaves similarly in terms of inference of implementation to the `Send` and `Sync` traits. The purpose of this trait is to encode what types are safe to cross a `catch_unwind` boundary with no fear of unwind safety.

## What is unwind safety?

In Rust a function can "return" early if it either panics or calls a function which transitively panics. This sort of control flow is not always anticipated, and has the possibility of causing subtle bugs through a combination of two critical components:

1. A data structure is in a temporarily invalid state when the thread panics.
2. This broken invariant is then later observed.

Typically in Rust, it is difficult to perform step (2) because catching a panic involves either spawning a thread (which in turns makes it difficult to later witness broken invariants) or using the `catch_unwind` function in this module. Additionally, even if an invariant is witnessed, it typically isn't a problem in Rust because there are no uninitialized values (like in C or C++).

It is possible, however, for logical invariants to be broken in Rust, which can end up causing behavioral bugs. Another key aspect of unwind safety in Rust is that, in the absence of `unsafe` code, a panic cannot lead to memory unsafety.

That was a bit of a whirlwind tour of unwind safety, but for more information about unwind safety and how it applies to Rust, see an associated RFC.

## What is `UnwindSafe`?

Now that we've got an idea of what unwind safety is in Rust, it's also important to understand what this trait represents. As mentioned above, one way to witness broken invariants is through the `catch_unwind` function in this module as it allows catching a panic and then re-using the environment of the closure.

Simply put, a type `T` implements `UnwindSafe` if it cannot easily allow witnessing a broken invariant through the use of `catch_unwind` (catching a panic). This trait is an auto trait, so it is automatically implemented for many types, and it is also structurally composed (e.g., a struct is unwind safe if all of its components are unwind safe).

Note, however, that this is not an unsafe trait, so there is not a succinct contract that this trait is providing. Instead it is intended as more of a "speed bump" to alert users of `catch_unwind` that broken invariants may be witnessed and may need to be accounted for.

## Who implements `UnwindSafe`?

Types such as `&mut T` and `&RefCell<T>` are examples which are not unwind safe. The general idea is that any mutable state which can be shared across `catch_unwind` is not unwind safe by default. This is because it is very easy to witness a broken invariant outside of `catch_unwind` as the data is simply accessed as usual.

Types like `&Mutex<T>`, however, are unwind safe because they implement poisoning by default. They still allow witnessing a broken invariant, but they already provide their own "speed bumps" to do so.

## When should `UnwindSafe` be used?

It is not intended that most types or functions need to worry about this trait. It is only used as a bound on the `catch_unwind` function and as mentioned above, the lack of `unsafe` means it is mostly an advisory. The `AssertUnwindSafe` wrapper struct can be used to force this trait to be implemented for any closed over variables passed to `catch_unwind`.

## Implementations on Foreign Types

### `impl UnwindSafe for Argument`

### `impl UnwindSafe for FormatSpec`

### `impl UnwindSafe for Alignment`

### `impl UnwindSafe for Count`

### `impl UnwindSafe for Position`

### `impl<T: UnwindSafe + ?Sized> UnwindSafe for Unique<T>`[src]

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## Implementors

### `impl<'_, T: RefUnwindSafe + ?Sized> UnwindSafe for &'_ T`[src]

### `impl<'_, T: ?Sized> !UnwindSafe for &'_ mut T`[src]

### `impl<K, V, S> UnwindSafe for HashMap<K, V, S> where
K: UnwindSafe,
V: UnwindSafe,
S: UnwindSafe,` [src]

### `impl<T> UnwindSafe for AssertUnwindSafe<T>`[src]

### `impl<T: RefUnwindSafe + ?Sized> UnwindSafe for *const T`[src]

### `impl<T: RefUnwindSafe + ?Sized> UnwindSafe for *mut T`[src]

### `impl<T: RefUnwindSafe + ?Sized> UnwindSafe for NonNull<T>`[src]

### `impl<T: RefUnwindSafe + ?Sized> UnwindSafe for Rc<T>`[src]

### `impl<T: RefUnwindSafe + ?Sized> UnwindSafe for Arc<T>`[src]

### `impl<T: ?Sized> UnwindSafe for Mutex<T>`[src]

### `impl<T: ?Sized> UnwindSafe for RwLock<T>`[src]

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## Auto implementors

### `impl !UnwindSafe for std::io::Error`

### `impl !UnwindSafe for Command`

### `impl !UnwindSafe for std::sync::Once`

### `impl !UnwindSafe for Thread`

### `impl UnwindSafe for std::cmp::Ordering`

### `impl UnwindSafe for CollectionAllocErr`

### `impl UnwindSafe for Infallible`

### `impl UnwindSafe for VarError`

### `impl UnwindSafe for c_void`

### `impl UnwindSafe for std::fmt::Alignment`

### `impl UnwindSafe for ErrorKind`

### `impl UnwindSafe for SeekFrom`

### `impl UnwindSafe for IpAddr`

### `impl UnwindSafe for Ipv6MulticastScope`

### `impl UnwindSafe for Shutdown`

### `impl UnwindSafe for std::net::SocketAddr`

### `impl UnwindSafe for FpCategory`

### `impl UnwindSafe for IntErrorKind`

### `impl UnwindSafe for SearchStep`

### `impl UnwindSafe for std::sync::atomic::Ordering`

### `impl UnwindSafe for RecvTimeoutError`

### `impl UnwindSafe for TryRecvError`

### `impl UnwindSafe for char`

### `impl UnwindSafe for f32`

### `impl UnwindSafe for f64`

### `impl UnwindSafe for i128`

### `impl UnwindSafe for i16`

### `impl UnwindSafe for i32`

### `impl UnwindSafe for i64`

### `impl UnwindSafe for i8`

### `impl UnwindSafe for isize`

### `impl UnwindSafe for [u8]`

### `impl UnwindSafe for str`

### `impl UnwindSafe for u128`

### `impl UnwindSafe for u16`

### `impl UnwindSafe for u32`

### `impl UnwindSafe for u64`

### `impl UnwindSafe for u8`

### `impl UnwindSafe for usize`

### `impl UnwindSafe for AllocErr`

### `impl UnwindSafe for CannotReallocInPlace`

### `impl UnwindSafe for Excess`

### `impl UnwindSafe for Global`

### `impl UnwindSafe for Layout`

### `impl UnwindSafe for LayoutErr`

### `impl UnwindSafe for System`

### `impl UnwindSafe for TypeId`

### `impl UnwindSafe for TryFromSliceError`

### `impl UnwindSafe for std::ascii::EscapeDefault`

### `impl UnwindSafe for BorrowError`

### `impl UnwindSafe for BorrowMutError`

### `impl UnwindSafe for CharTryFromError`

### `impl UnwindSafe for DecodeUtf16Error`

### `impl UnwindSafe for std::char::EscapeDebug`

### `impl UnwindSafe for std::char::EscapeDefault`

### `impl UnwindSafe for std::char::EscapeUnicode`

### `impl UnwindSafe for ParseCharError`

### `impl UnwindSafe for ToLowercase`

### `impl UnwindSafe for ToUppercase`

### `impl UnwindSafe for UnicodeVersion`

### `impl UnwindSafe for DefaultHasher`

### `impl UnwindSafe for RandomState`

### `impl UnwindSafe for Args`

### `impl UnwindSafe for ArgsOs`

### `impl UnwindSafe for JoinPathsError`

### `impl UnwindSafe for Vars`

### `impl UnwindSafe for VarsOs`

### `impl UnwindSafe for CStr`

### `impl UnwindSafe for CString`

### `impl UnwindSafe for FromBytesWithNulError`

### `impl UnwindSafe for IntoStringError`

### `impl UnwindSafe for NulError`

### `impl UnwindSafe for OsStr`

### `impl UnwindSafe for OsString`

### `impl UnwindSafe for std::fmt::Error`

### `impl UnwindSafe for DirBuilder`

### `impl UnwindSafe for DirEntry`

### `impl UnwindSafe for File`

### `impl UnwindSafe for FileType`

### `impl UnwindSafe for Metadata`

### `impl UnwindSafe for OpenOptions`

### `impl UnwindSafe for Permissions`

### `impl UnwindSafe for ReadDir`

### `impl UnwindSafe for SipHasher`

### `impl UnwindSafe for std::io::Empty`

### `impl UnwindSafe for Initializer`

### `impl UnwindSafe for std::io::Repeat`

### `impl UnwindSafe for Sink`

### `impl UnwindSafe for Stderr`

### `impl UnwindSafe for Stdin`

### `impl UnwindSafe for Stdout`

### `impl UnwindSafe for PhantomPinned`

### `impl UnwindSafe for AddrParseError`

### `impl UnwindSafe for Ipv4Addr`

### `impl UnwindSafe for Ipv6Addr`

### `impl UnwindSafe for SocketAddrV4`

### `impl UnwindSafe for SocketAddrV6`

### `impl UnwindSafe for TcpListener`

### `impl UnwindSafe for TcpStream`

### `impl UnwindSafe for UdpSocket`

### `impl UnwindSafe for NonZeroI128`

### `impl UnwindSafe for NonZeroI16`

### `impl UnwindSafe for NonZeroI32`

### `impl UnwindSafe for NonZeroI64`

### `impl UnwindSafe for NonZeroI8`

### `impl UnwindSafe for NonZeroIsize`

### `impl UnwindSafe for NonZeroU128`

### `impl UnwindSafe for NonZeroU16`

### `impl UnwindSafe for NonZeroU32`

### `impl UnwindSafe for NonZeroU64`

### `impl UnwindSafe for NonZeroU8`

### `impl UnwindSafe for NonZeroUsize`

### `impl UnwindSafe for ParseFloatError`

### `impl UnwindSafe for ParseIntError`

### `impl UnwindSafe for TryFromIntError`

### `impl UnwindSafe for RangeFull`

### `impl UnwindSafe for NoneError`

### `impl UnwindSafe for stat`

### `impl UnwindSafe for std::os::unix::net::SocketAddr`

### `impl UnwindSafe for UnixDatagram`

### `impl UnwindSafe for UnixListener`

### `impl UnwindSafe for UnixStream`

### `impl UnwindSafe for Path`

### `impl UnwindSafe for PathBuf`

### `impl UnwindSafe for StripPrefixError`

### `impl UnwindSafe for Child`

### `impl UnwindSafe for ChildStderr`

### `impl UnwindSafe for ChildStdin`

### `impl UnwindSafe for ChildStdout`

### `impl UnwindSafe for ExitCode`

### `impl UnwindSafe for ExitStatus`

### `impl UnwindSafe for Output`

### `impl UnwindSafe for Stdio`

### `impl UnwindSafe for TraitObject`

### `impl UnwindSafe for ParseBoolError`

### `impl UnwindSafe for Utf8Error`

### `impl UnwindSafe for FromUtf16Error`

### `impl UnwindSafe for FromUtf8Error`

### `impl UnwindSafe for String`

### `impl UnwindSafe for AtomicBool`

### `impl UnwindSafe for AtomicI16`

### `impl UnwindSafe for AtomicI32`

### `impl UnwindSafe for AtomicI64`

### `impl UnwindSafe for AtomicI8`

### `impl UnwindSafe for AtomicIsize`

### `impl UnwindSafe for AtomicU16`

### `impl UnwindSafe for AtomicU32`

### `impl UnwindSafe for AtomicU64`

### `impl UnwindSafe for AtomicU8`

### `impl UnwindSafe for AtomicUsize`

### `impl UnwindSafe for RecvError`

### `impl UnwindSafe for Barrier`

### `impl UnwindSafe for BarrierWaitResult`

### `impl UnwindSafe for Condvar`

### `impl UnwindSafe for OnceState`

### `impl UnwindSafe for WaitTimeoutResult`

### `impl UnwindSafe for RawWaker`

### `impl UnwindSafe for RawWakerVTable`

### `impl UnwindSafe for Waker`

### `impl UnwindSafe for AccessError`

### `impl UnwindSafe for Builder`

### `impl UnwindSafe for ThreadId`

### `impl UnwindSafe for Duration`

### `impl UnwindSafe for Instant`

### `impl UnwindSafe for SystemTime`

### `impl UnwindSafe for SystemTimeError`

### `impl<'a> !UnwindSafe for ErrorIter<'a>`

### `impl<'a> !UnwindSafe for Arguments<'a>`

### `impl<'a> !UnwindSafe for Formatter<'a>`

### `impl<'a> !UnwindSafe for IoSliceMut<'a>`

### `impl<'a> !UnwindSafe for PanicInfo<'a>`

### `impl<'a> UnwindSafe for Component<'a>`

### `impl<'a> UnwindSafe for Prefix<'a>`

### `impl<'a> UnwindSafe for SplitPaths<'a>`

### `impl<'a> UnwindSafe for IoSlice<'a>`

### `impl<'a> UnwindSafe for StderrLock<'a>`

### `impl<'a> UnwindSafe for StdinLock<'a>`

### `impl<'a> UnwindSafe for StdoutLock<'a>`

### `impl<'a> UnwindSafe for std::net::Incoming<'a>`

### `impl<'a> UnwindSafe for std::os::unix::net::Incoming<'a>`

### `impl<'a> UnwindSafe for EncodeWide<'a>`

### `impl<'a> UnwindSafe for Location<'a>`

### `impl<'a> UnwindSafe for Ancestors<'a>`

### `impl<'a> UnwindSafe for Components<'a>`

### `impl<'a> UnwindSafe for Display<'a>`

### `impl<'a> UnwindSafe for std::path::Iter<'a>`

### `impl<'a> UnwindSafe for PrefixComponent<'a>`

### `impl<'a> UnwindSafe for CharSearcher<'a>`

### `impl<'a> UnwindSafe for std::str::Bytes<'a>`

### `impl<'a> UnwindSafe for CharIndices<'a>`

### `impl<'a> UnwindSafe for Chars<'a>`

### `impl<'a> UnwindSafe for EncodeUtf16<'a>`

### `impl<'a> UnwindSafe for std::str::EscapeDebug<'a>`

### `impl<'a> UnwindSafe for std::str::EscapeDefault<'a>`

### `impl<'a> UnwindSafe for std::str::EscapeUnicode<'a>`

### `impl<'a> UnwindSafe for std::str::Lines<'a>`

### `impl<'a> UnwindSafe for LinesAny<'a>`

### `impl<'a> UnwindSafe for SplitAsciiWhitespace<'a>`

### `impl<'a> UnwindSafe for SplitWhitespace<'a>`

### `impl<'a> UnwindSafe for std::string::Drain<'a>`

### `impl<'a> UnwindSafe for Context<'a>`

### `impl<'a, 'b> !UnwindSafe for DebugList<'a, 'b>`

### `impl<'a, 'b> !UnwindSafe for DebugMap<'a, 'b>`

### `impl<'a, 'b> !UnwindSafe for DebugSet<'a, 'b>`

### `impl<'a, 'b> !UnwindSafe for DebugStruct<'a, 'b>`

### `impl<'a, 'b> !UnwindSafe for DebugTuple<'a, 'b>`

### `impl<'a, 'b> UnwindSafe for CharSliceSearcher<'a, 'b>`

### `impl<'a, 'b> UnwindSafe for StrSearcher<'a, 'b>`

### `impl<'a, 'f> !UnwindSafe for VaList<'a, 'f>`

### `impl<'a, A> !UnwindSafe for std::option::IterMut<'a, A>`

### `impl<'a, A> UnwindSafe for std::option::Iter<'a, A> where
A: RefUnwindSafe,`

### `impl<'a, B: ?Sized> UnwindSafe for Cow<'a, B> where
B: RefUnwindSafe,
<B as ToOwned>::Owned: UnwindSafe,`

### `impl<'a, F> UnwindSafe for CharPredicateSearcher<'a, F> where
F: MultiCharEq + UnwindSafe,`

### `impl<'a, I> UnwindSafe for Splice<'a, I> where
I: UnwindSafe,
<I as Iterator>::Item: RefUnwindSafe,`

### `impl<'a, K> UnwindSafe for std::collections::hash_set::Drain<'a, K> where
K: RefUnwindSafe + UnwindSafe,`

### `impl<'a, K> UnwindSafe for std::collections::hash_set::Iter<'a, K> where
K: RefUnwindSafe,`

### `impl<'a, K, V> !UnwindSafe for std::collections::btree_map::Entry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::hash_map::Entry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::btree_map::IterMut<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::btree_map::OccupiedEntry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for RangeMut<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::btree_map::VacantEntry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::btree_map::ValuesMut<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::hash_map::IterMut<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::hash_map::OccupiedEntry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for RawOccupiedEntryMut<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::hash_map::VacantEntry<'a, K, V>`

### `impl<'a, K, V> !UnwindSafe for std::collections::hash_map::ValuesMut<'a, K, V>`

### `impl<'a, K, V> UnwindSafe for std::collections::btree_map::Iter<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::btree_map::Keys<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::btree_map::Range<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::btree_map::Values<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::hash_map::Drain<'a, K, V> where
K: RefUnwindSafe + UnwindSafe,
V: RefUnwindSafe + UnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::hash_map::Iter<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::hash_map::Keys<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V> UnwindSafe for std::collections::hash_map::Values<'a, K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, K, V, S> !UnwindSafe for RawEntryMut<'a, K, V, S>`

### `impl<'a, K, V, S> !UnwindSafe for RawEntryBuilderMut<'a, K, V, S>`

### `impl<'a, K, V, S> !UnwindSafe for RawVacantEntryMut<'a, K, V, S>`

### `impl<'a, K, V, S> UnwindSafe for RawEntryBuilder<'a, K, V, S> where
K: RefUnwindSafe,
S: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<'a, P> UnwindSafe for MatchIndices<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for Matches<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for RMatchIndices<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for RMatches<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for std::str::RSplit<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for std::str::RSplitN<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for RSplitTerminator<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for std::str::Split<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for std::str::SplitN<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, P> UnwindSafe for SplitTerminator<'a, P> where
<P as Pattern<'a>>::Searcher: UnwindSafe,`

### `impl<'a, T> !UnwindSafe for PeekMut<'a, T>`

### `impl<'a, T> !UnwindSafe for std::collections::linked_list::IterMut<'a, T>`

### `impl<'a, T> !UnwindSafe for std::collections::vec_deque::IterMut<'a, T>`

### `impl<'a, T> !UnwindSafe for std::result::IterMut<'a, T>`

### `impl<'a, T> !UnwindSafe for ChunksExactMut<'a, T>`

### `impl<'a, T> !UnwindSafe for ChunksMut<'a, T>`

### `impl<'a, T> !UnwindSafe for std::slice::IterMut<'a, T>`

### `impl<'a, T> !UnwindSafe for RChunksExactMut<'a, T>`

### `impl<'a, T> !UnwindSafe for RChunksMut<'a, T>`

### `impl<'a, T> !UnwindSafe for std::sync::mpsc::Iter<'a, T>`

### `impl<'a, T> !UnwindSafe for TryIter<'a, T>`

### `impl<'a, T> UnwindSafe for std::collections::binary_heap::Drain<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::binary_heap::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::Difference<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::Intersection<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::Range<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::SymmetricDifference<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::btree_set::Union<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::linked_list::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::vec_deque::Drain<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::collections::vec_deque::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::result::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for Chunks<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for ChunksExact<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::slice::Iter<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for RChunks<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for RChunksExact<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for Windows<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T> UnwindSafe for std::vec::Drain<'a, T> where
T: RefUnwindSafe,`

### `impl<'a, T, F> !UnwindSafe for std::collections::linked_list::DrainFilter<'a, T, F>`

### `impl<'a, T, F> !UnwindSafe for std::vec::DrainFilter<'a, T, F>`

### `impl<'a, T, P> !UnwindSafe for RSplitMut<'a, T, P>`

### `impl<'a, T, P> !UnwindSafe for RSplitNMut<'a, T, P>`

### `impl<'a, T, P> !UnwindSafe for SplitMut<'a, T, P>`

### `impl<'a, T, P> !UnwindSafe for SplitNMut<'a, T, P>`

### `impl<'a, T, P> UnwindSafe for std::slice::RSplit<'a, T, P> where
P: UnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, P> UnwindSafe for std::slice::RSplitN<'a, T, P> where
P: UnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, P> UnwindSafe for std::slice::Split<'a, T, P> where
P: UnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, P> UnwindSafe for std::slice::SplitN<'a, T, P> where
P: UnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, S> UnwindSafe for std::collections::hash_set::Difference<'a, T, S> where
S: RefUnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, S> UnwindSafe for std::collections::hash_set::Intersection<'a, T, S> where
S: RefUnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, S> UnwindSafe for std::collections::hash_set::SymmetricDifference<'a, T, S> where
S: RefUnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T, S> UnwindSafe for std::collections::hash_set::Union<'a, T, S> where
S: RefUnwindSafe,
T: RefUnwindSafe,`

### `impl<'a, T: ?Sized> UnwindSafe for MutexGuard<'a, T>`

### `impl<'a, T: ?Sized> UnwindSafe for RwLockReadGuard<'a, T>`

### `impl<'a, T: ?Sized> UnwindSafe for RwLockWriteGuard<'a, T>`

### `impl<'b, T> !UnwindSafe for Ref<'b, T>`

### `impl<'b, T> !UnwindSafe for RefMut<'b, T>`

### `impl<'f> UnwindSafe for VaListImpl<'f>`

### `impl<A> UnwindSafe for std::iter::Repeat<A> where
A: UnwindSafe,`

### `impl<A> UnwindSafe for std::option::IntoIter<A> where
A: UnwindSafe,`

### `impl<A, B> UnwindSafe for std::iter::Chain<A, B> where
A: UnwindSafe,
B: UnwindSafe,`

### `impl<A, B> UnwindSafe for Zip<A, B> where
A: UnwindSafe,
B: UnwindSafe,`

### `impl<B> UnwindSafe for std::io::Lines<B> where
B: UnwindSafe,`

### `impl<B> UnwindSafe for std::io::Split<B> where
B: UnwindSafe,`

### `impl<F> UnwindSafe for FromFn<F> where
F: UnwindSafe,`

### `impl<F> UnwindSafe for OnceWith<F> where
F: UnwindSafe,`

### `impl<F> UnwindSafe for RepeatWith<F> where
F: UnwindSafe,`

### `impl<H> UnwindSafe for BuildHasherDefault<H> where
H: UnwindSafe,`

### `impl<I> UnwindSafe for DecodeUtf16<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Cloned<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Copied<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Cycle<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Enumerate<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Flatten<I> where
I: UnwindSafe,
<<I as Iterator>::Item as IntoIterator>::IntoIter: UnwindSafe,`

### `impl<I> UnwindSafe for Fuse<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for Peekable<I> where
I: UnwindSafe,
<I as Iterator>::Item: UnwindSafe,`

### `impl<I> UnwindSafe for Skip<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for StepBy<I> where
I: UnwindSafe,`

### `impl<I> UnwindSafe for std::iter::Take<I> where
I: UnwindSafe,`

### `impl<I, F> UnwindSafe for FilterMap<I, F> where
F: UnwindSafe,
I: UnwindSafe,`

### `impl<I, F> UnwindSafe for Inspect<I, F> where
F: UnwindSafe,
I: UnwindSafe,`

### `impl<I, F> UnwindSafe for Map<I, F> where
F: UnwindSafe,
I: UnwindSafe,`

### `impl<I, P> UnwindSafe for Filter<I, P> where
I: UnwindSafe,
P: UnwindSafe,`

### `impl<I, P> UnwindSafe for SkipWhile<I, P> where
I: UnwindSafe,
P: UnwindSafe,`

### `impl<I, P> UnwindSafe for TakeWhile<I, P> where
I: UnwindSafe,
P: UnwindSafe,`

### `impl<I, St, F> UnwindSafe for Scan<I, St, F> where
F: UnwindSafe,
I: UnwindSafe,
St: UnwindSafe,`

### `impl<I, U, F> UnwindSafe for FlatMap<I, U, F> where
F: UnwindSafe,
I: UnwindSafe,
<U as IntoIterator>::IntoIter: UnwindSafe,`

### `impl<Idx> UnwindSafe for std::ops::Range<Idx> where
Idx: UnwindSafe,`

### `impl<Idx> UnwindSafe for RangeFrom<Idx> where
Idx: UnwindSafe,`

### `impl<Idx> UnwindSafe for RangeInclusive<Idx> where
Idx: UnwindSafe,`

### `impl<Idx> UnwindSafe for RangeTo<Idx> where
Idx: UnwindSafe,`

### `impl<Idx> UnwindSafe for RangeToInclusive<Idx> where
Idx: UnwindSafe,`

### `impl<K> UnwindSafe for std::collections::hash_set::IntoIter<K> where
K: RefUnwindSafe + UnwindSafe,`

### `impl<K, V> UnwindSafe for BTreeMap<K, V> where
K: RefUnwindSafe + UnwindSafe,
V: RefUnwindSafe + UnwindSafe,`

### `impl<K, V> UnwindSafe for std::collections::btree_map::IntoIter<K, V> where
K: RefUnwindSafe,
V: RefUnwindSafe,`

### `impl<K, V> UnwindSafe for std::collections::hash_map::IntoIter<K, V> where
K: RefUnwindSafe + UnwindSafe,
V: RefUnwindSafe + UnwindSafe,`

### `impl<P> UnwindSafe for Pin<P> where
P: UnwindSafe,`

### `impl<R> UnwindSafe for BufReader<R> where
R: UnwindSafe,`

### `impl<R> UnwindSafe for std::io::Bytes<R> where
R: UnwindSafe,`

### `impl<T> !UnwindSafe for std::rc::Weak<T>`

### `impl<T> !UnwindSafe for std::sync::mpsc::IntoIter<T>`

### `impl<T> !UnwindSafe for Receiver<T>`

### `impl<T> !UnwindSafe for Sender<T>`

### `impl<T> !UnwindSafe for JoinHandle<T>`

### `impl<T> UnwindSafe for Bound<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Option<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for TryLockError<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for TrySendError<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Poll<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for [T] where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Reverse<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for BinaryHeap<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for std::collections::binary_heap::IntoIter<T> where
T: RefUnwindSafe + UnwindSafe,`

### `impl<T> UnwindSafe for BTreeSet<T> where
T: RefUnwindSafe + UnwindSafe,`

### `impl<T> UnwindSafe for std::collections::btree_set::IntoIter<T> where
T: RefUnwindSafe,`

### `impl<T> UnwindSafe for std::collections::linked_list::IntoIter<T> where
T: RefUnwindSafe + UnwindSafe,`

### `impl<T> UnwindSafe for LinkedList<T> where
T: RefUnwindSafe + UnwindSafe,`

### `impl<T> UnwindSafe for std::collections::vec_deque::IntoIter<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for VecDeque<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Cursor<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for std::io::Take<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for std::iter::Empty<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for std::iter::Once<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Rev<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for Discriminant<T>`

### `impl<T> UnwindSafe for Wrapping<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for std::result::IntoIter<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for AtomicPtr<T> where
T: RefUnwindSafe,`

### `impl<T> UnwindSafe for SendError<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for SyncSender<T>`

### `impl<T> UnwindSafe for PoisonError<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for LocalKey<T>`

### `impl<T> UnwindSafe for std::vec::IntoIter<T> where
T: RefUnwindSafe + UnwindSafe,`

### `impl<T> UnwindSafe for Vec<T> where
T: UnwindSafe,`

### `impl<T> UnwindSafe for MaybeUninit<T> where
T: UnwindSafe,`

### `impl<T, E> UnwindSafe for Result<T, E> where
E: UnwindSafe,
T: UnwindSafe,`

### `impl<T, F> UnwindSafe for Successors<T, F> where
F: UnwindSafe,
T: UnwindSafe,`

### `impl<T, S> UnwindSafe for HashSet<T, S> where
S: UnwindSafe,
T: UnwindSafe,`

### `impl<T, U> UnwindSafe for std::io::Chain<T, U> where
T: UnwindSafe,
U: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for Box<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for Cell<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for RefCell<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for UnsafeCell<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for PhantomData<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for ManuallyDrop<T> where
T: UnwindSafe,`

### `impl<T: ?Sized> UnwindSafe for std::sync::Weak<T> where
T: RefUnwindSafe,`

### `impl<W> !UnwindSafe for IntoInnerError<W>`

### `impl<W> UnwindSafe for BufWriter<W> where
W: UnwindSafe,`

### `impl<W> UnwindSafe for LineWriter<W> where
W: UnwindSafe,`

### `impl<Y, R> UnwindSafe for GeneratorState<Y, R> where
R: UnwindSafe,
Y: UnwindSafe,`

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