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<!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="Implementing this trait means that the concrete type is plain old data (POD). Precisely, by implementing `Pod` the programmer asserts that it is safe to read the type from binary slices provided to `read`, etc."><meta name="keywords" content="rust, rustlang, rust-lang, Pod"><title>Pod in zero - Rust</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../SourceCodePro-Semibold.ttf.woff2"><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="../ayu.css" disabled><link rel="stylesheet" type="text/css" href="../dark.css" disabled><link rel="stylesheet" type="text/css" href="../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../storage.js"></script><script src="../crates.js"></script><script defer src="../main.js"></script>
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<nav class="sidebar"><a class="sidebar-logo" href="../zero/index.html"><div class="logo-container"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></div>
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</a><h2 class="location"><a href="#">Pod</a></h2><div class="sidebar-elems"><section><div class="block"><h3 class="sidebar-title"><a href="#foreign-impls">Implementations on Foreign Types</a></h3><ul><li><a href="#impl-Pod-for-i16">i16</a></li><li><a href="#impl-Pod-for-i32">i32</a></li><li><a href="#impl-Pod-for-i64">i64</a></li><li><a href="#impl-Pod-for-i8">i8</a></li><li><a href="#impl-Pod-for-u16">u16</a></li><li><a href="#impl-Pod-for-u32">u32</a></li><li><a href="#impl-Pod-for-u64">u64</a></li><li><a href="#impl-Pod-for-u8">u8</a></li></ul></div><div class="block"><h3 class="sidebar-title"><a href="#implementors">Implementors</a></h3></div></section><h2 class="location"><a href="index.html">In zero</a></h2><div id="sidebar-vars" data-name="Pod" data-ty="trait" data-relpath=""></div><script defer src="sidebar-items.js"></script></div></nav><main><div class="width-limiter"><div class="sub-container"><a class="sub-logo-container" href="../zero/index.html"><img class="rust-logo" src="../rust-logo.svg" alt="logo"></a><nav class="sub"><div class="theme-picker hidden"><button id="theme-picker" aria-label="Pick another theme!" aria-haspopup="menu" title="themes"><img width="22" height="22" alt="Pick another theme!" src="../brush.svg"></button><div id="theme-choices" role="menu"></div></div><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><button type="button" id="help-button" title="help">?</button><a id="settings-menu" href="../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../wheel.svg"></a></div></form></nav></div><section id="main-content" class="content"><div class="main-heading">
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<h1 class="fqn"><span class="in-band">Trait <a href="index.html">zero</a>::<wbr><a class="trait" href="#">Pod</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../clipboard.svg" width="19" height="18" alt="Copy item path"></button></span></h1><span class="out-of-band"><a class="srclink" href="../src/zero/lib.rs.html#94">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><div class="docblock item-decl"><pre class="rust trait"><code>pub unsafe trait Pod: <a class="trait" href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a> { }</code></pre></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Implementing this trait means that the concrete type is plain old data (POD).
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Precisely, by implementing <code>Pod</code> the programmer asserts that it is safe to
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read the type from binary slices provided to <code>read</code>, etc.</p>
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<p>Some guidelines for when <code>Pod</code> may be implemented (note that whether <code>Pod</code>
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should be implemented or not is a function of both the type and the input
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data. I.e., just because a type is <code>Pod</code> in one context does not mean it
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should be in another):</p>
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<ul>
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<li>primitive numeric types (<code>u8</code>, <code>i64</code>, <code>f32</code>, etc.) are fine,</li>
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<li>bools are fine, if the provided data ensures they may have only the values
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<code>0</code> or <code>1</code> (note that this is a stricter requirement that C),</li>
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<li>structs containing only <code>Pod</code> data are fine,</li>
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<li>structs must be <code>repr(C)</code> or <code>repr(packed)</code>, if the former, the supplied
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data must have the correct alignment,</li>
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<li>enums must have valid discriminants in the supplied data, this is probably
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only feasible if they have a specified representation,</li>
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<li>there must not be invalid enum variants in the data,</li>
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<li>any kind of pointer is probably a bad idea. Theoretically one could make
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raw pointers work.</li>
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</ul>
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</div></details><h2 id="foreign-impls" class="small-section-header">Implementations on Foreign Types<a href="#foreign-impls" class="anchor"></a></h2><section id="impl-Pod-for-u8" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#96">source</a></span><a href="#impl-Pod-for-u8" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.u8.html">u8</a></h3></section><section id="impl-Pod-for-u16" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#97">source</a></span><a href="#impl-Pod-for-u16" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.u16.html">u16</a></h3></section><section id="impl-Pod-for-u32" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#98">source</a></span><a href="#impl-Pod-for-u32" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.u32.html">u32</a></h3></section><section id="impl-Pod-for-u64" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#99">source</a></span><a href="#impl-Pod-for-u64" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.u64.html">u64</a></h3></section><section id="impl-Pod-for-i8" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#100">source</a></span><a href="#impl-Pod-for-i8" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.i8.html">i8</a></h3></section><section id="impl-Pod-for-i16" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#101">source</a></span><a href="#impl-Pod-for-i16" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.i16.html">i16</a></h3></section><section id="impl-Pod-for-i32" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#102">source</a></span><a href="#impl-Pod-for-i32" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.i32.html">i32</a></h3></section><section id="impl-Pod-for-i64" class="impl has-srclink"><span class="rightside"><a class="srclink" href="../src/zero/lib.rs.html#103">source</a></span><a href="#impl-Pod-for-i64" class="anchor"></a><h3 class="code-header in-band">impl <a class="trait" href="trait.Pod.html" title="trait zero::Pod">Pod</a> for <a class="primitive" href="https://doc.rust-lang.org/nightly/core/primitive.i64.html">i64</a></h3></section><h2 id="implementors" class="small-section-header">Implementors<a href="#implementors" class="anchor"></a></h2><div class="item-list" id="implementors-list"></div><script type="text/javascript" src="../implementors/zero/trait.Pod.js" async></script></section><section id="search" class="content hidden"></section></div></main><div id="rustdoc-vars" data-root-path="../" data-current-crate="zero" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.62.0-nightly (1f7fb6413 2022-04-10)" ></div>
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