<!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="API documentation for the Rust `PhantomData` struct in crate `core`."><meta name="keywords" content="rust, rustlang, rust-lang, PhantomData"><title>core::marker::PhantomData - Rust</title><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css"><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><script src="../../storage.js"></script><link rel="shortcut icon" href="https://doc.rust-lang.org/favicon.ico"></head><body class="rustdoc struct"><!--[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='../../core/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a><p class='location'>Struct PhantomData</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Hash">Hash</a><a href="#impl-PartialEq">PartialEq</a><a href="#impl-Eq">Eq</a><a href="#impl-PartialOrd">PartialOrd</a><a href="#impl-Ord">Ord</a><a href="#impl-Copy">Copy</a><a href="#impl-Clone">Clone</a><a href="#impl-Default">Default</a><a href="#impl-Debug">Debug</a></div><a class="sidebar-title" href="#synthetic-implementations">Auto Trait Implementations</a><div class="sidebar-links"><a href="#impl-Send">Send</a><a href="#impl-Sync">Sync</a></div></div><p class='location'><a href='../index.html'>core</a>::<wbr><a href='index.html'>marker</a></p><script>window.sidebarCurrent = {name: 'PhantomData', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../theme.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><input class="search-input" name="search" autocomplete="off" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><a id="settings-menu" href="../../settings.html"><img src="../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><h1 class='fqn'><span class='in-band'>Struct <a href='../index.html'>core</a>::<wbr><a href='index.html'>marker</a>::<wbr><a class="struct" href=''>PhantomData</a></span><span class='out-of-band'><span class='since' title='Stable since Rust version 1.0.0'>1.0.0</span><span id='render-detail'><a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class='inner'>−</span>]</a></span><a class='srclink' href='../../src/core/marker.rs.html#573' title='goto source code'>[src]</a></span></h1><div class="docblock type-decl"><pre class='rust struct'><div class="docblock attributes">#[lang = "phantom_data"]
</div>pub struct PhantomData<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>>;</pre></div><div class='docblock'><p>Zero-sized type used to mark things that "act like" they own a <code>T</code>.</p>
<p>Adding a <code>PhantomData<T></code> field to your type tells the compiler that your
type acts as though it stores a value of type <code>T</code>, even though it doesn't
really. This information is used when computing certain safety properties.</p>
<p>For a more in-depth explanation of how to use <code>PhantomData<T></code>, please see
<a href="../../nomicon/phantom-data.html">the Nomicon</a>.</p>
<h1 id="a-ghastly-note-" class="section-header"><a href="#a-ghastly-note-">A ghastly note 👻👻👻</a></h1>
<p>Though they both have scary names, <code>PhantomData</code> and 'phantom types' are
related, but not identical. A phantom type parameter is simply a type
parameter which is never used. In Rust, this often causes the compiler to
complain, and the solution is to add a "dummy" use by way of <code>PhantomData</code>.</p>
<h1 id="examples" class="section-header"><a href="#examples">Examples</a></h1><h2 id="unused-lifetime-parameters" class="section-header"><a href="#unused-lifetime-parameters">Unused lifetime parameters</a></h2>
<p>Perhaps the most common use case for <code>PhantomData</code> is a struct that has an
unused lifetime parameter, typically as part of some unsafe code. For
example, here is a struct <code>Slice</code> that has two pointers of type <code>*const T</code>,
presumably pointing into an array somewhere:</p>
<div class='information'><div class='tooltip compile_fail'>ⓘ<span class='tooltiptext'>This example deliberately fails to compile</span></div></div><pre class="rust rust-example-rendered compile_fail">
<span class="kw">struct</span> <span class="ident">Slice</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span><span class="op">></span> {
<span class="ident">start</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">T</span>,
<span class="ident">end</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">T</span>,
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Astruct%20Slice%3C'a%2C%20T%3E%20%7B%0A%20%20%20%20start%3A%20*const%20T%2C%0A%20%20%20%20end%3A%20*const%20T%2C%0A%7D%0A%7D">Run</a></pre>
<p>The intention is that the underlying data is only valid for the
lifetime <code>'a</code>, so <code>Slice</code> should not outlive <code>'a</code>. However, this
intent is not expressed in the code, since there are no uses of
the lifetime <code>'a</code> and hence it is not clear what data it applies
to. We can correct this by telling the compiler to act <em>as if</em> the
<code>Slice</code> struct contained a reference <code>&'a T</code>:</p>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">marker</span>::<span class="ident">PhantomData</span>;
<span class="kw">struct</span> <span class="ident">Slice</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span>: <span class="lifetime">'a</span><span class="op">></span> {
<span class="ident">start</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">T</span>,
<span class="ident">end</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">T</span>,
<span class="ident">phantom</span>: <span class="ident">PhantomData</span><span class="op"><</span><span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">T</span><span class="op">></span>,
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Amarker%3A%3APhantomData%3B%0A%0A%23%5Ballow(dead_code)%5D%0Astruct%20Slice%3C'a%2C%20T%3A%20'a%3E%20%7B%0A%20%20%20%20start%3A%20*const%20T%2C%0A%20%20%20%20end%3A%20*const%20T%2C%0A%20%20%20%20phantom%3A%20PhantomData%3C%26'a%20T%3E%2C%0A%7D%0A%7D">Run</a></pre>
<p>This also in turn requires the annotation <code>T: 'a</code>, indicating
that any references in <code>T</code> are valid over the lifetime <code>'a</code>.</p>
<p>When initializing a <code>Slice</code> you simply provide the value
<code>PhantomData</code> for the field <code>phantom</code>:</p>
<pre class="rust rust-example-rendered">
<span class="kw">fn</span> <span class="ident">borrow_vec</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span><span class="op">></span>(<span class="ident">vec</span>: <span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">Vec</span><span class="op"><</span><span class="ident">T</span><span class="op">></span>) <span class="op">-></span> <span class="ident">Slice</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span><span class="op">></span> {
<span class="kw">let</span> <span class="ident">ptr</span> <span class="op">=</span> <span class="ident">vec</span>.<span class="ident">as_ptr</span>();
<span class="ident">Slice</span> {
<span class="ident">start</span>: <span class="ident">ptr</span>,
<span class="ident">end</span>: <span class="kw">unsafe</span> { <span class="ident">ptr</span>.<span class="ident">offset</span>(<span class="ident">vec</span>.<span class="ident">len</span>() <span class="kw">as</span> <span class="ident">isize</span>) },
<span class="ident">phantom</span>: <span class="ident">PhantomData</span>,
}
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0A%23!%5Ballow(dead_code)%5D%0Afn%20main()%20%7B%0Ause%20std%3A%3Amarker%3A%3APhantomData%3B%0Astruct%20Slice%3C'a%2C%20T%3A%20'a%3E%20%7B%0A%20%20%20%20start%3A%20*const%20T%2C%0A%20%20%20%20end%3A%20*const%20T%2C%0A%20%20%20%20phantom%3A%20PhantomData%3C%26'a%20T%3E%2C%0A%7D%0Afn%20borrow_vec%3C'a%2C%20T%3E(vec%3A%20%26'a%20Vec%3CT%3E)%20-%3E%20Slice%3C'a%2C%20T%3E%20%7B%0A%20%20%20%20let%20ptr%20%3D%20vec.as_ptr()%3B%0A%20%20%20%20Slice%20%7B%0A%20%20%20%20%20%20%20%20start%3A%20ptr%2C%0A%20%20%20%20%20%20%20%20end%3A%20unsafe%20%7B%20ptr.offset(vec.len()%20as%20isize)%20%7D%2C%0A%20%20%20%20%20%20%20%20phantom%3A%20PhantomData%2C%0A%20%20%20%20%7D%0A%7D%0A%7D">Run</a></pre>
<h2 id="unused-type-parameters" class="section-header"><a href="#unused-type-parameters">Unused type parameters</a></h2>
<p>It sometimes happens that you have unused type parameters which
indicate what type of data a struct is "tied" to, even though that
data is not actually found in the struct itself. Here is an
example where this arises with <a href="../../book/first-edition/ffi.html">FFI</a>. The foreign interface uses
handles of type <code>*mut ()</code> to refer to Rust values of different
types. We track the Rust type using a phantom type parameter on
the struct <code>ExternalResource</code> which wraps a handle.</p>
<pre class="rust rust-example-rendered">
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">marker</span>::<span class="ident">PhantomData</span>;
<span class="kw">use</span> <span class="ident">std</span>::<span class="ident">mem</span>;
<span class="kw">struct</span> <span class="ident">ExternalResource</span><span class="op"><</span><span class="ident">R</span><span class="op">></span> {
<span class="ident">resource_handle</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> (),
<span class="ident">resource_type</span>: <span class="ident">PhantomData</span><span class="op"><</span><span class="ident">R</span><span class="op">></span>,
}
<span class="kw">impl</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">ResType</span><span class="op">></span> <span class="ident">ExternalResource</span><span class="op"><</span><span class="ident">R</span><span class="op">></span> {
<span class="kw">fn</span> <span class="ident">new</span>() <span class="op">-></span> <span class="ident">ExternalResource</span><span class="op"><</span><span class="ident">R</span><span class="op">></span> {
<span class="kw">let</span> <span class="ident">size_of_res</span> <span class="op">=</span> <span class="ident">mem</span>::<span class="ident">size_of</span>::<span class="op"><</span><span class="ident">R</span><span class="op">></span>();
<span class="ident">ExternalResource</span> {
<span class="ident">resource_handle</span>: <span class="ident">foreign_lib</span>::<span class="ident">new</span>(<span class="ident">size_of_res</span>),
<span class="ident">resource_type</span>: <span class="ident">PhantomData</span>,
}
}
<span class="kw">fn</span> <span class="ident">do_stuff</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">param</span>: <span class="ident">ParamType</span>) {
<span class="kw">let</span> <span class="ident">foreign_params</span> <span class="op">=</span> <span class="ident">convert_params</span>(<span class="ident">param</span>);
<span class="ident">foreign_lib</span>::<span class="ident">do_stuff</span>(<span class="self">self</span>.<span class="ident">resource_handle</span>, <span class="ident">foreign_params</span>);
}
}<a class="test-arrow" target="_blank" href="https://play.rust-lang.org/?code=%23!%5Ballow(unused)%5D%0A%23!%5Ballow(dead_code)%5D%0Afn%20main()%20%7B%0Atrait%20ResType%20%7B%20%7D%0Astruct%20ParamType%3B%0Amod%20foreign_lib%20%7B%0A%20%20%20%20pub%20fn%20new(_%3A%20usize)%20-%3E%20*mut%20()%20%7B%2042%20as%20*mut%20()%20%7D%0A%20%20%20%20pub%20fn%20do_stuff(_%3A%20*mut%20()%2C%20_%3A%20usize)%20%7B%7D%0A%7D%0Afn%20convert_params(_%3A%20ParamType)%20-%3E%20usize%20%7B%2042%20%7D%0Ause%20std%3A%3Amarker%3A%3APhantomData%3B%0Ause%20std%3A%3Amem%3B%0A%0Astruct%20ExternalResource%3CR%3E%20%7B%0A%20%20%20resource_handle%3A%20*mut%20()%2C%0A%20%20%20resource_type%3A%20PhantomData%3CR%3E%2C%0A%7D%0A%0Aimpl%3CR%3A%20ResType%3E%20ExternalResource%3CR%3E%20%7B%0A%20%20%20%20fn%20new()%20-%3E%20ExternalResource%3CR%3E%20%7B%0A%20%20%20%20%20%20%20%20let%20size_of_res%20%3D%20mem%3A%3Asize_of%3A%3A%3CR%3E()%3B%0A%20%20%20%20%20%20%20%20ExternalResource%20%7B%0A%20%20%20%20%20%20%20%20%20%20%20%20resource_handle%3A%20foreign_lib%3A%3Anew(size_of_res)%2C%0A%20%20%20%20%20%20%20%20%20%20%20%20resource_type%3A%20PhantomData%2C%0A%20%20%20%20%20%20%20%20%7D%0A%20%20%20%20%7D%0A%0A%20%20%20%20fn%20do_stuff(%26self%2C%20param%3A%20ParamType)%20%7B%0A%20%20%20%20%20%20%20%20let%20foreign_params%20%3D%20convert_params(param)%3B%0A%20%20%20%20%20%20%20%20foreign_lib%3A%3Ado_stuff(self.resource_handle%2C%20foreign_params)%3B%0A%20%20%20%20%7D%0A%7D%0A%7D">Run</a></pre>
<h2 id="ownership-and-the-drop-check" class="section-header"><a href="#ownership-and-the-drop-check">Ownership and the drop check</a></h2>
<p>Adding a field of type <code>PhantomData<T></code> indicates that your
type owns data of type <code>T</code>. This in turn implies that when your
type is dropped, it may drop one or more instances of the type
<code>T</code>. This has bearing on the Rust compiler's <a href="../../nomicon/dropck.html">drop check</a>
analysis.</p>
<p>If your struct does not in fact <em>own</em> the data of type <code>T</code>, it is
better to use a reference type, like <code>PhantomData<&'a T></code>
(ideally) or <code>PhantomData<*const T></code> (if no lifetime applies), so
as not to indicate ownership.</p>
</div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<div id='implementations-list'><h3 id='impl-Hash' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/hash/trait.Hash.html" title="trait core::hash::Hash">Hash</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Hash' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#388-392' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.hash' class="method"><span id='hash.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/hash/trait.Hash.html#tymethod.hash' class='fnname'>hash</a><H: <a class="trait" href="../../core/hash/trait.Hasher.html" title="trait core::hash::Hasher">Hasher</a>>(&self, _: &mut H)</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#390-391' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Feeds this value into the given [<code>Hasher</code>]. <a href="../../core/hash/trait.Hash.html#tymethod.hash">Read more</a></p>
</div><h4 id='method.hash_slice' class="method"><span id='hash_slice.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/hash/trait.Hash.html#method.hash_slice' class='fnname'>hash_slice</a><H: <a class="trait" href="../../core/hash/trait.Hasher.html" title="trait core::hash::Hasher">Hasher</a>>(data: &[Self], state: &mut H) <span class="where fmt-newline">where<br> Self: <a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span></td><td><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.3.0'>1.3.0</div><a class='srclink' href='../../src/core/hash/mod.rs.html#203-209' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Feeds a slice of this type into the given [<code>Hasher</code>]. <a href="../../core/hash/trait.Hash.html#method.hash_slice">Read more</a></p>
</div></div><h3 id='impl-PartialEq' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/cmp/trait.PartialEq.html" title="trait core::cmp::PartialEq">PartialEq</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-PartialEq' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#395-399' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.eq' class="method"><span id='eq.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/cmp/trait.PartialEq.html#tymethod.eq' class='fnname'>eq</a>(&self, _other: &<a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T>) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#396-398' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests for <code>self</code> and <code>other</code> values to be equal, and is used by <code>==</code>. <a href="../../core/cmp/trait.PartialEq.html#tymethod.eq">Read more</a></p>
</div><h4 id='method.ne' class="method"><span id='ne.v' class='invisible'><table class='table-display'><tbody><tr><td><code><div class="docblock attributes">#[must_use]
</div>fn <a href='../../core/cmp/trait.PartialEq.html#method.ne' class='fnname'>ne</a>(&self, other: &Rhs) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/cmp.rs.html#123' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests for <code>!=</code>.</p>
</div></div><h3 id='impl-Eq' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/cmp/trait.Eq.html" title="trait core::cmp::Eq">Eq</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Eq' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#402-403' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'></div><h3 id='impl-PartialOrd' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/cmp/trait.PartialOrd.html" title="trait core::cmp::PartialOrd">PartialOrd</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-PartialOrd' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#406-410' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.partial_cmp' class="method"><span id='partial_cmp.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/cmp/trait.PartialOrd.html#tymethod.partial_cmp' class='fnname'>partial_cmp</a>(&self, _other: &<a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T>) -> <a class="enum" href="../../core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="enum" href="../../core/cmp/enum.Ordering.html" title="enum core::cmp::Ordering">Ordering</a>></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#407-409' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method returns an ordering between <code>self</code> and <code>other</code> values if one exists. <a href="../../core/cmp/trait.PartialOrd.html#tymethod.partial_cmp">Read more</a></p>
</div><h4 id='method.lt' class="method"><span id='lt.v' class='invisible'><table class='table-display'><tbody><tr><td><code><div class="docblock attributes">#[must_use]
</div>fn <a href='../../core/cmp/trait.PartialOrd.html#method.lt' class='fnname'>lt</a>(&self, other: &Rhs) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/cmp.rs.html#657-662' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests less than (for <code>self</code> and <code>other</code>) and is used by the <code><</code> operator. <a href="../../core/cmp/trait.PartialOrd.html#method.lt">Read more</a></p>
</div><h4 id='method.le' class="method"><span id='le.v' class='invisible'><table class='table-display'><tbody><tr><td><code><div class="docblock attributes">#[must_use]
</div>fn <a href='../../core/cmp/trait.PartialOrd.html#method.le' class='fnname'>le</a>(&self, other: &Rhs) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/cmp.rs.html#679-684' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests less than or equal to (for <code>self</code> and <code>other</code>) and is used by the <code><=</code> operator. <a href="../../core/cmp/trait.PartialOrd.html#method.le">Read more</a></p>
</div><h4 id='method.gt' class="method"><span id='gt.v' class='invisible'><table class='table-display'><tbody><tr><td><code><div class="docblock attributes">#[must_use]
</div>fn <a href='../../core/cmp/trait.PartialOrd.html#method.gt' class='fnname'>gt</a>(&self, other: &Rhs) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/cmp.rs.html#700-705' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests greater than (for <code>self</code> and <code>other</code>) and is used by the <code>></code> operator. <a href="../../core/cmp/trait.PartialOrd.html#method.gt">Read more</a></p>
</div><h4 id='method.ge' class="method"><span id='ge.v' class='invisible'><table class='table-display'><tbody><tr><td><code><div class="docblock attributes">#[must_use]
</div>fn <a href='../../core/cmp/trait.PartialOrd.html#method.ge' class='fnname'>ge</a>(&self, other: &Rhs) -> bool</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/cmp.rs.html#722-727' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method tests greater than or equal to (for <code>self</code> and <code>other</code>) and is used by the <code>>=</code> operator. <a href="../../core/cmp/trait.PartialOrd.html#method.ge">Read more</a></p>
</div></div><h3 id='impl-Ord' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Ord' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#413-417' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.cmp' class="method"><span id='cmp.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/cmp/trait.Ord.html#tymethod.cmp' class='fnname'>cmp</a>(&self, _other: &<a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T>) -> <a class="enum" href="../../core/cmp/enum.Ordering.html" title="enum core::cmp::Ordering">Ordering</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#414-416' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>This method returns an <code>Ordering</code> between <code>self</code> and <code>other</code>. <a href="../../core/cmp/trait.Ord.html#tymethod.cmp">Read more</a></p>
</div><h4 id='method.max' class="method"><span id='max.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/cmp/trait.Ord.html#method.max' class='fnname'>max</a>(self, other: Self) -> Self <span class="where fmt-newline">where<br> Self: <a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span></td><td><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.21.0'>1.21.0</div><a class='srclink' href='../../src/core/cmp.rs.html#469-472' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Compares and returns the maximum of two values. <a href="../../core/cmp/trait.Ord.html#method.max">Read more</a></p>
</div><h4 id='method.min' class="method"><span id='min.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/cmp/trait.Ord.html#method.min' class='fnname'>min</a>(self, other: Self) -> Self <span class="where fmt-newline">where<br> Self: <a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>, </span></code></span></td><td><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.21.0'>1.21.0</div><a class='srclink' href='../../src/core/cmp.rs.html#485-488' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Compares and returns the minimum of two values. <a href="../../core/cmp/trait.Ord.html#method.min">Read more</a></p>
</div></div><h3 id='impl-Copy' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/marker/trait.Copy.html" title="trait core::marker::Copy">Copy</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Copy' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#420' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'></div><h3 id='impl-Clone' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Clone' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#423-427' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.clone' class="method"><span id='clone.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/clone/trait.Clone.html#tymethod.clone' class='fnname'>clone</a>(&self) -> <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#424-426' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Returns a copy of the value. <a href="../../core/clone/trait.Clone.html#tymethod.clone">Read more</a></p>
</div><h4 id='method.clone_from' class="method"><span id='clone_from.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/clone/trait.Clone.html#method.clone_from' class='fnname'>clone_from</a>(&mut self, source: &Self)</code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/clone.rs.html#130-132' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Performs copy-assignment from <code>source</code>. <a href="../../core/clone/trait.Clone.html#method.clone_from">Read more</a></p>
</div></div><h3 id='impl-Default' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/default/trait.Default.html" title="trait core::default::Default">Default</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Default' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#430-434' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.default' class="method"><span id='default.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/default/trait.Default.html#tymethod.default' class='fnname'>default</a>() -> <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/marker.rs.html#431-433' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Returns the "default value" for a type. <a href="../../core/default/trait.Default.html#tymethod.default">Read more</a></p>
</div></div><h3 id='impl-Debug' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T></code><a href='#impl-Debug' class='anchor'></a></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#2046-2050' title='goto source code'>[src]</a></span></td></tr></tbody></table></h3><div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><table class='table-display'><tbody><tr><td><code>fn <a href='../../core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, f: &mut <a class="struct" href="../../core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -> <a class="type" href="../../core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></code></span></td><td><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../../src/core/fmt/mod.rs.html#2047-2049' title='goto source code'>[src]</a></td></tr></tbody></table></span></h4><div class='docblock'><p>Formats the value using the given formatter. <a href="../../core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></div></div>
<h2 id='synthetic-implementations' class='small-section-header'>
Auto Trait Implementations<a href='#synthetic-implementations' class='anchor'></a>
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<div id='synthetic-implementations-list'>
<h3 id='impl-Send' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T> <span class="where fmt-newline">where<br> T: <a class="trait" href="../../core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>, </span></code><a href='#impl-Send' class='anchor'></a></span></td><td><span class='out-of-band'></span></td></tr></tbody></table></h3><div class='impl-items'></div><h3 id='impl-Sync' class='impl'><span class='in-band'><table class='table-display'><tbody><tr><td><code>impl<T: ?<a class="trait" href="../../core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>> <a class="trait" href="../../core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="../../core/marker/struct.PhantomData.html" title="struct core::marker::PhantomData">PhantomData</a><T> <span class="where fmt-newline">where<br> T: <a class="trait" href="../../core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a>, </span></code><a href='#impl-Sync' class='anchor'></a></span></td><td><span class='out-of-band'></span></td></tr></tbody></table></h3><div class='impl-items'></div></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 = "core";</script><script src="../../aliases.js"></script><script src="../../main.js"></script><script defer src="../../search-index.js"></script></body></html>
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