<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source to the Rust file `src/libstd/panic.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>panic.rs.html -- source</title><link rel="stylesheet" type="text/css" href="../../normalize1.35.0.css"><link rel="stylesheet" type="text/css" href="../../rustdoc1.35.0.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../dark1.35.0.css"><link rel="stylesheet" type="text/css" href="../../light1.35.0.css" id="themeStyle"><script src="../../storage1.35.0.js"></script><noscript><link rel="stylesheet" href="../../noscript1.35.0.css"></noscript><link rel="shortcut icon" href="../../favicon1.35.0.ico"><style type="text/css">#crate-search{background-image:url("../../down-arrow1.35.0.svg");}</style></head><body class="rustdoc source"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">☰</div><a href='../../std/index.html'><img src='../../rust-logo1.35.0.png' alt='logo' width='100'></a></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../brush1.35.0.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../theme1.35.0.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><div><select id="crate-search"><option value="All crates">All crates</option></select><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"></div><a id="settings-menu" href="../../settings.html"><img src="../../wheel1.35.0.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><pre class="line-numbers"><span id="1"> 1</span>
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</pre><div class="example-wrap"><pre class="rust ">
<span class="doccomment">//! Panic support in the standard library.</span>
<span class="attribute">#![<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"std_panic"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">any</span>::<span class="ident">Any</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">cell</span>::<span class="ident">UnsafeCell</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">fmt</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">future</span>::<span class="ident">Future</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">pin</span>::<span class="ident">Pin</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">ops</span>::{<span class="ident">Deref</span>, <span class="ident">DerefMut</span>};
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">panicking</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">ptr</span>::{<span class="ident">Unique</span>, <span class="ident">NonNull</span>};
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">rc</span>::<span class="ident">Rc</span>;
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">sync</span>::{<span class="ident">Arc</span>, <span class="ident">Mutex</span>, <span class="ident">RwLock</span>, <span class="ident">atomic</span>};
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">task</span>::{<span class="ident">Context</span>, <span class="ident">Poll</span>};
<span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">thread</span>::<span class="prelude-ty">Result</span>;
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"panic_hooks"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.10.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">use</span> <span class="kw">crate</span>::<span class="ident">panicking</span>::{<span class="ident">take_hook</span>, <span class="ident">set_hook</span>};
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"panic_hooks"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.10.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">panic</span>::{<span class="ident">PanicInfo</span>, <span class="ident">Location</span>};
<span class="doccomment">/// A marker trait which represents "panic safe" types in Rust.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This trait is implemented by default for many types and behaves similarly in</span>
<span class="doccomment">/// terms of inference of implementation to the [`Send`] and [`Sync`] traits. The</span>
<span class="doccomment">/// purpose of this trait is to encode what types are safe to cross a [`catch_unwind`]</span>
<span class="doccomment">/// boundary with no fear of unwind safety.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Send`]: ../marker/trait.Send.html</span>
<span class="doccomment">/// [`Sync`]: ../marker/trait.Sync.html</span>
<span class="doccomment">/// [`catch_unwind`]: ./fn.catch_unwind.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## What is unwind safety?</span>
<span class="doccomment">///</span>
<span class="doccomment">/// In Rust a function can "return" early if it either panics or calls a</span>
<span class="doccomment">/// function which transitively panics. This sort of control flow is not always</span>
<span class="doccomment">/// anticipated, and has the possibility of causing subtle bugs through a</span>
<span class="doccomment">/// combination of two critical components:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// 1. A data structure is in a temporarily invalid state when the thread</span>
<span class="doccomment">/// panics.</span>
<span class="doccomment">/// 2. This broken invariant is then later observed.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Typically in Rust, it is difficult to perform step (2) because catching a</span>
<span class="doccomment">/// panic involves either spawning a thread (which in turns makes it difficult</span>
<span class="doccomment">/// to later witness broken invariants) or using the `catch_unwind` function in this</span>
<span class="doccomment">/// module. Additionally, even if an invariant is witnessed, it typically isn't a</span>
<span class="doccomment">/// problem in Rust because there are no uninitialized values (like in C or C++).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// It is possible, however, for **logical** invariants to be broken in Rust,</span>
<span class="doccomment">/// which can end up causing behavioral bugs. Another key aspect of unwind safety</span>
<span class="doccomment">/// in Rust is that, in the absence of `unsafe` code, a panic cannot lead to</span>
<span class="doccomment">/// memory unsafety.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// That was a bit of a whirlwind tour of unwind safety, but for more information</span>
<span class="doccomment">/// about unwind safety and how it applies to Rust, see an [associated RFC][rfc].</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1236-stabilize-catch-panic.md</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## What is `UnwindSafe`?</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Now that we've got an idea of what unwind safety is in Rust, it's also</span>
<span class="doccomment">/// important to understand what this trait represents. As mentioned above, one</span>
<span class="doccomment">/// way to witness broken invariants is through the `catch_unwind` function in this</span>
<span class="doccomment">/// module as it allows catching a panic and then re-using the environment of</span>
<span class="doccomment">/// the closure.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Simply put, a type `T` implements `UnwindSafe` if it cannot easily allow</span>
<span class="doccomment">/// witnessing a broken invariant through the use of `catch_unwind` (catching a</span>
<span class="doccomment">/// panic). This trait is an auto trait, so it is automatically implemented for</span>
<span class="doccomment">/// many types, and it is also structurally composed (e.g., a struct is unwind</span>
<span class="doccomment">/// safe if all of its components are unwind safe).</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note, however, that this is not an unsafe trait, so there is not a succinct</span>
<span class="doccomment">/// contract that this trait is providing. Instead it is intended as more of a</span>
<span class="doccomment">/// "speed bump" to alert users of `catch_unwind` that broken invariants may be</span>
<span class="doccomment">/// witnessed and may need to be accounted for.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## Who implements `UnwindSafe`?</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Types such as `&mut T` and `&RefCell<T>` are examples which are **not**</span>
<span class="doccomment">/// unwind safe. The general idea is that any mutable state which can be shared</span>
<span class="doccomment">/// across `catch_unwind` is not unwind safe by default. This is because it is very</span>
<span class="doccomment">/// easy to witness a broken invariant outside of `catch_unwind` as the data is</span>
<span class="doccomment">/// simply accessed as usual.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Types like `&Mutex<T>`, however, are unwind safe because they implement</span>
<span class="doccomment">/// poisoning by default. They still allow witnessing a broken invariant, but</span>
<span class="doccomment">/// they already provide their own "speed bumps" to do so.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ## When should `UnwindSafe` be used?</span>
<span class="doccomment">///</span>
<span class="doccomment">/// It is not intended that most types or functions need to worry about this trait.</span>
<span class="doccomment">/// It is only used as a bound on the `catch_unwind` function and as mentioned</span>
<span class="doccomment">/// above, the lack of `unsafe` means it is mostly an advisory. The</span>
<span class="doccomment">/// [`AssertUnwindSafe`] wrapper struct can be used to force this trait to be</span>
<span class="doccomment">/// implemented for any closed over variables passed to `catch_unwind`.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`AssertUnwindSafe`]: ./struct.AssertUnwindSafe.html</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="attribute">#[<span class="ident">rustc_on_unimplemented</span>(
<span class="ident">message</span><span class="op">=</span><span class="string">"the type `{Self}` may not be safely transferred across an unwind boundary"</span>,
<span class="ident">label</span><span class="op">=</span><span class="string">"`{Self}` may not be safely transferred across an unwind boundary"</span>,
)]</span>
<span class="kw">pub</span> <span class="ident">auto</span> <span class="kw">trait</span> <span class="ident">UnwindSafe</span> {}
<span class="doccomment">/// A marker trait representing types where a shared reference is considered</span>
<span class="doccomment">/// unwind safe.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This trait is namely not implemented by [`UnsafeCell`], the root of all</span>
<span class="doccomment">/// interior mutability.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This is a "helper marker trait" used to provide impl blocks for the</span>
<span class="doccomment">/// [`UnwindSafe`] trait, for more information see that documentation.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`UnsafeCell`]: ../cell/struct.UnsafeCell.html</span>
<span class="doccomment">/// [`UnwindSafe`]: ./trait.UnwindSafe.html</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="attribute">#[<span class="ident">rustc_on_unimplemented</span>(
<span class="ident">message</span><span class="op">=</span><span class="string">"the type `{Self}` may contain interior mutability and a reference may not be safely \
transferrable across a catch_unwind boundary"</span>,
<span class="ident">label</span><span class="op">=</span><span class="string">"`{Self}` may contain interior mutability and a reference may not be safely \
transferrable across a catch_unwind boundary"</span>,
)]</span>
<span class="kw">pub</span> <span class="ident">auto</span> <span class="kw">trait</span> <span class="ident">RefUnwindSafe</span> {}
<span class="doccomment">/// A simple wrapper around a type to assert that it is unwind safe.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// When using [`catch_unwind`] it may be the case that some of the closed over</span>
<span class="doccomment">/// variables are not unwind safe. For example if `&mut T` is captured the</span>
<span class="doccomment">/// compiler will generate a warning indicating that it is not unwind safe. It</span>
<span class="doccomment">/// may not be the case, however, that this is actually a problem due to the</span>
<span class="doccomment">/// specific usage of [`catch_unwind`] if unwind safety is specifically taken into</span>
<span class="doccomment">/// account. This wrapper struct is useful for a quick and lightweight</span>
<span class="doccomment">/// annotation that a variable is indeed unwind safe.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`catch_unwind`]: ./fn.catch_unwind.html</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// One way to use `AssertUnwindSafe` is to assert that the entire closure</span>
<span class="doccomment">/// itself is unwind safe, bypassing all checks for all variables:</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::panic::{self, AssertUnwindSafe};</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let mut variable = 4;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // This code will not compile because the closure captures `&mut variable`</span>
<span class="doccomment">/// // which is not considered unwind safe by default.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // panic::catch_unwind(|| {</span>
<span class="doccomment">/// // variable += 3;</span>
<span class="doccomment">/// // });</span>
<span class="doccomment">///</span>
<span class="doccomment">/// // This, however, will compile due to the `AssertUnwindSafe` wrapper</span>
<span class="doccomment">/// let result = panic::catch_unwind(AssertUnwindSafe(|| {</span>
<span class="doccomment">/// variable += 3;</span>
<span class="doccomment">/// }));</span>
<span class="doccomment">/// // ...</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Wrapping the entire closure amounts to a blanket assertion that all captured</span>
<span class="doccomment">/// variables are unwind safe. This has the downside that if new captures are</span>
<span class="doccomment">/// added in the future, they will also be considered unwind safe. Therefore,</span>
<span class="doccomment">/// you may prefer to just wrap individual captures, as shown below. This is</span>
<span class="doccomment">/// more annotation, but it ensures that if a new capture is added which is not</span>
<span class="doccomment">/// unwind safe, you will get a compilation error at that time, which will</span>
<span class="doccomment">/// allow you to consider whether that new capture in fact represent a bug or</span>
<span class="doccomment">/// not.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::panic::{self, AssertUnwindSafe};</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let mut variable = 4;</span>
<span class="doccomment">/// let other_capture = 3;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let result = {</span>
<span class="doccomment">/// let mut wrapper = AssertUnwindSafe(&mut variable);</span>
<span class="doccomment">/// panic::catch_unwind(move || {</span>
<span class="doccomment">/// **wrapper += other_capture;</span>
<span class="doccomment">/// })</span>
<span class="doccomment">/// };</span>
<span class="doccomment">/// // ...</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span>(
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">pub</span> <span class="ident">T</span>
);
<span class="comment">// Implementations of the `UnwindSafe` trait:</span>
<span class="comment">//</span>
<span class="comment">// * By default everything is unwind safe</span>
<span class="comment">// * pointers T contains mutability of some form are not unwind safe</span>
<span class="comment">// * Unique, an owning pointer, lifts an implementation</span>
<span class="comment">// * Types like Mutex/RwLock which are explicitly poisoned are unwind safe</span>
<span class="comment">// * Our custom AssertUnwindSafe wrapper is indeed unwind safe</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="op">!</span><span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">T</span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="kw-2">&</span><span class="ident">T</span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">T</span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">T</span> {}
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"ptr_internals"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">UnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">Unique</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"nonnull"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.25.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">NonNull</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">Mutex</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">RwLock</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="comment">// not covered via the Shared impl above b/c the inner contents use</span>
<span class="comment">// Cell/AtomicUsize, but the usage here is unwind safe so we can lift the</span>
<span class="comment">// impl up one level to Arc/Rc itself</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">Rc</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">RefUnwindSafe</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">UnwindSafe</span> <span class="kw">for</span> <span class="ident">Arc</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="comment">// Pretty simple implementations for the `RefUnwindSafe` marker trait,</span>
<span class="comment">// basically just saying that `UnsafeCell` is the</span>
<span class="comment">// only thing which doesn't implement it (which then transitively applies to</span>
<span class="comment">// everything else).</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="op">!</span><span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">UnsafeCell</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_lock_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.12.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">Mutex</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_lock_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.12.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">RwLock</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"ptr"</span>)]</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_atomic_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicIsize</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"8"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicI8</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"16"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicI16</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"32"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicI32</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"64"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicI64</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"128"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicI128</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"ptr"</span>)]</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_atomic_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicUsize</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"8"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicU8</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"16"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicU16</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"32"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicU32</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"64"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicU64</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"128"</span>)]</span>
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"integer_atomics"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"32976"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicU128</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"8"</span>)]</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_atomic_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicBool</span> {}
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">target_has_atomic</span> <span class="op">=</span> <span class="string">"ptr"</span>)]</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"unwind_safe_atomic_refs"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.14.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">RefUnwindSafe</span> <span class="kw">for</span> <span class="ident">atomic</span>::<span class="ident">AtomicPtr</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">Deref</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {
<span class="kw">type</span> <span class="ident">Target</span> <span class="op">=</span> <span class="ident">T</span>;
<span class="kw">fn</span> <span class="ident">deref</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="ident">T</span> {
<span class="kw-2">&</span><span class="self">self</span>.<span class="number">0</span>
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="ident">DerefMut</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">deref_mut</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) <span class="op">-></span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">T</span> {
<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>.<span class="number">0</span>
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">R</span>, <span class="ident">F</span>: <span class="ident">FnOnce</span>() <span class="op">-></span> <span class="ident">R</span><span class="op">></span> <span class="ident">FnOnce</span><span class="op"><</span>()<span class="op">></span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">F</span><span class="op">></span> {
<span class="kw">type</span> <span class="ident">Output</span> <span class="op">=</span> <span class="ident">R</span>;
<span class="kw">extern</span> <span class="string">"rust-call"</span> <span class="kw">fn</span> <span class="ident">call_once</span>(<span class="self">self</span>, <span class="ident">_args</span>: ()) <span class="op">-></span> <span class="ident">R</span> {
(<span class="self">self</span>.<span class="number">0</span>)()
}
}
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"std_debug"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.16.0"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">fmt</span>::<span class="ident">Debug</span><span class="op">></span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span><span class="op"><</span><span class="lifetime">'_</span><span class="op">></span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> {
<span class="ident">f</span>.<span class="ident">debug_tuple</span>(<span class="string">"AssertUnwindSafe"</span>)
.<span class="ident">field</span>(<span class="kw-2">&</span><span class="self">self</span>.<span class="number">0</span>)
.<span class="ident">finish</span>()
}
}
<span class="attribute">#[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"futures_api"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"50547"</span>)]</span>
<span class="kw">impl</span><span class="op"><</span><span class="ident">F</span>: <span class="ident">Future</span><span class="op">></span> <span class="ident">Future</span> <span class="kw">for</span> <span class="ident">AssertUnwindSafe</span><span class="op"><</span><span class="ident">F</span><span class="op">></span> {
<span class="kw">type</span> <span class="ident">Output</span> <span class="op">=</span> <span class="ident">F</span>::<span class="ident">Output</span>;
<span class="kw">fn</span> <span class="ident">poll</span>(<span class="self">self</span>: <span class="ident">Pin</span><span class="op"><</span><span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">Self</span><span class="op">></span>, <span class="ident">cx</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">Context</span><span class="op"><</span><span class="lifetime">'_</span><span class="op">></span>) <span class="op">-></span> <span class="ident">Poll</span><span class="op"><</span><span class="self">Self</span>::<span class="ident">Output</span><span class="op">></span> {
<span class="kw">let</span> <span class="ident">pinned_field</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">Pin</span>::<span class="ident">map_unchecked_mut</span>(<span class="self">self</span>, <span class="op">|</span><span class="ident">x</span><span class="op">|</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">x</span>.<span class="number">0</span>) };
<span class="ident">F</span>::<span class="ident">poll</span>(<span class="ident">pinned_field</span>, <span class="ident">cx</span>)
}
}
<span class="doccomment">/// Invokes a closure, capturing the cause of an unwinding panic if one occurs.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This function will return `Ok` with the closure's result if the closure</span>
<span class="doccomment">/// does not panic, and will return `Err(cause)` if the closure panics. The</span>
<span class="doccomment">/// `cause` returned is the object with which panic was originally invoked.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// It is currently undefined behavior to unwind from Rust code into foreign</span>
<span class="doccomment">/// code, so this function is particularly useful when Rust is called from</span>
<span class="doccomment">/// another language (normally C). This can run arbitrary Rust code, capturing a</span>
<span class="doccomment">/// panic and allowing a graceful handling of the error.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// It is **not** recommended to use this function for a general try/catch</span>
<span class="doccomment">/// mechanism. The [`Result`] type is more appropriate to use for functions that</span>
<span class="doccomment">/// can fail on a regular basis. Additionally, this function is not guaranteed</span>
<span class="doccomment">/// to catch all panics, see the "Notes" section below.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`Result`]: ../result/enum.Result.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// The closure provided is required to adhere to the [`UnwindSafe`] trait to ensure</span>
<span class="doccomment">/// that all captured variables are safe to cross this boundary. The purpose of</span>
<span class="doccomment">/// this bound is to encode the concept of [exception safety][rfc] in the type</span>
<span class="doccomment">/// system. Most usage of this function should not need to worry about this</span>
<span class="doccomment">/// bound as programs are naturally unwind safe without `unsafe` code. If it</span>
<span class="doccomment">/// becomes a problem the [`AssertUnwindSafe`] wrapper struct can be used to quickly</span>
<span class="doccomment">/// assert that the usage here is indeed unwind safe.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`AssertUnwindSafe`]: ./struct.AssertUnwindSafe.html</span>
<span class="doccomment">/// [`UnwindSafe`]: ./trait.UnwindSafe.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1236-stabilize-catch-panic.md</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Notes</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note that this function **may not catch all panics** in Rust. A panic in</span>
<span class="doccomment">/// Rust is not always implemented via unwinding, but can be implemented by</span>
<span class="doccomment">/// aborting the process as well. This function *only* catches unwinding panics,</span>
<span class="doccomment">/// not those that abort the process.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```</span>
<span class="doccomment">/// use std::panic;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let result = panic::catch_unwind(|| {</span>
<span class="doccomment">/// println!("hello!");</span>
<span class="doccomment">/// });</span>
<span class="doccomment">/// assert!(result.is_ok());</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let result = panic::catch_unwind(|| {</span>
<span class="doccomment">/// panic!("oh no!");</span>
<span class="doccomment">/// });</span>
<span class="doccomment">/// assert!(result.is_err());</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"catch_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">catch_unwind</span><span class="op"><</span><span class="ident">F</span>: <span class="ident">FnOnce</span>() <span class="op">-></span> <span class="ident">R</span> <span class="op">+</span> <span class="ident">UnwindSafe</span>, <span class="ident">R</span><span class="op">></span>(<span class="ident">f</span>: <span class="ident">F</span>) <span class="op">-></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">R</span><span class="op">></span> {
<span class="kw">unsafe</span> {
<span class="ident">panicking</span>::<span class="ident">r#try</span>(<span class="ident">f</span>)
}
}
<span class="doccomment">/// Triggers a panic without invoking the panic hook.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This is designed to be used in conjunction with [`catch_unwind`] to, for</span>
<span class="doccomment">/// example, carry a panic across a layer of C code.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// [`catch_unwind`]: ./fn.catch_unwind.html</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Notes</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Note that panics in Rust are not always implemented via unwinding, but they</span>
<span class="doccomment">/// may be implemented by aborting the process. If this function is called when</span>
<span class="doccomment">/// panics are implemented this way then this function will abort the process,</span>
<span class="doccomment">/// not trigger an unwind.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// # Examples</span>
<span class="doccomment">///</span>
<span class="doccomment">/// ```should_panic</span>
<span class="doccomment">/// use std::panic;</span>
<span class="doccomment">///</span>
<span class="doccomment">/// let result = panic::catch_unwind(|| {</span>
<span class="doccomment">/// panic!("oh no!");</span>
<span class="doccomment">/// });</span>
<span class="doccomment">///</span>
<span class="doccomment">/// if let Err(err) = result {</span>
<span class="doccomment">/// panic::resume_unwind(err);</span>
<span class="doccomment">/// }</span>
<span class="doccomment">/// ```</span>
<span class="attribute">#[<span class="ident">stable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"resume_unwind"</span>, <span class="ident">since</span> <span class="op">=</span> <span class="string">"1.9.0"</span>)]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">resume_unwind</span>(<span class="ident">payload</span>: <span class="ident">Box</span><span class="op"><</span><span class="kw">dyn</span> <span class="ident">Any</span> <span class="op">+</span> <span class="ident">Send</span><span class="op">></span>) <span class="op">-></span> <span class="op">!</span> {
<span class="ident">panicking</span>::<span class="ident">update_count_then_panic</span>(<span class="ident">payload</span>)
}
</pre></div>
</section><section id="search" class="content hidden"></section><section class="footer"></section><aside id="help" class="hidden"><div><h1 class="hidden">Help</h1><div class="shortcuts"><h2>Keyboard Shortcuts</h2><dl><dt><kbd>?</kbd></dt><dd>Show this help dialog</dd><dt><kbd>S</kbd></dt><dd>Focus the search field</dd><dt><kbd>↑</kbd></dt><dd>Move up in search results</dd><dt><kbd>↓</kbd></dt><dd>Move down in search results</dd><dt><kbd>↹</kbd></dt><dd>Switch tab</dd><dt><kbd>⏎</kbd></dt><dd>Go to active search result</dd><dt><kbd>+</kbd></dt><dd>Expand all sections</dd><dt><kbd>-</kbd></dt><dd>Collapse all sections</dd></dl></div><div class="infos"><h2>Search Tricks</h2><p>Prefix searches with a type followed by a colon (e.g., <code>fn:</code>) to restrict the search to a given type.</p><p>Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>.</p><p>Search functions by type signature (e.g., <code>vec -> usize</code> or <code>* -> vec</code>)</p><p>Search multiple things at once by splitting your query with comma (e.g., <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../../";window.currentCrate = "std";</script><script src="../../aliases.js"></script><script src="../../main1.35.0.js"></script><script src="../../source-script1.35.0.js"></script><script src="../../source-files.js"></script><script defer src="../../search-index.js"></script></body></html>
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