<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="A field value of an erased type."><title>Value in tracing_core::field - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-46f98efaafac5295.ttf.woff2,FiraSans-Regular-018c141bf0843ffd.woff2,FiraSans-Medium-8f9a781e4970d388.woff2,SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2,SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../../static.files/${f}">`).join(""))</script><linkrel="stylesheet"href="../../static.files/normalize-76eba96aa4d2e634.css"><linkrel="stylesheet"href="../../static.files/rustdoc-dd39b87e5fcfba68.css"><metaname="rustdoc-vars"data-root-path="../../"data-static-root-path="../../static.files/"data-current-crate="tracing_core"data-themes=""data-resource-suffix=""data-rustdoc-version="1.80.0 (051478957 2024-07-21)"data-channel="1.80.0"data-search-js="search-d52510db62a78183.js"data-settings-js="settings-4313503d2e1961c2.js"><scriptsrc="../../static.files/storage-118b08c4c78b968e.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../../static.files/main-20a3ad099b048cf2.js"></script><noscript><linkrel="stylesheet"href="../../static.files/noscript-df360f571f6edeae.css"></noscript><linkrel="alternate icon"type="image/png"href="../../static.files/favicon-32x32-422f7d1d52889060.png"><linkrel="icon"type="image/svg+xml"href="../../static.files/favicon-2c020d218678b618.svg"></head><bodyclass="rustdoc trait"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="mobile-topbar"><buttonclass="sidebar-menu-toggle"title="show sidebar"></button><aclass="logo-container"href="../../tracing_core/index.html"><imgsrc="https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png"alt=""></a></nav><navclass="sidebar"><divclass="sidebar-crate"><aclass="logo-container"href="../../tracing_core/index.html"><imgsrc="https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png"alt="logo"></a><h2><ahref="../../tracing_core/index.html">tracing_core</a><spanclass="version">0.1.32</span></h2></div><h2class="location"><ahref="#">Value</a></h2><divclass="sidebar-elems"><section><h3><ahref="#required-methods">Required Methods</a></h3><ulclass="block"><li><ahref="#tymethod.record">record</a></li></ul><h3><ahref="#foreign-impls">Implementations on Foreign Types</a></h3><ulclass="block"><li><ahref="#impl-Value-for-%26T">&'a T</a></li><li><ahref="#impl-Value-for-%26mut+T">&'a mut T</a></li><li><ahref="#impl-Value-for-Arguments%3C'a%3E">Arguments<'a></a></li><li><ahref="#impl-Value-for-Box%3CT%3E">Box<T></a></li><li><ahref="#impl-Value-for-NonZero%3Ci128%3E">NonZeroI128</a></li><li><ahref="#impl-Value-for-NonZero%3Ci16%3E">NonZeroI16</a></li><li><ahref="#impl-Value-for-NonZero%3Ci32%3E">NonZeroI32</a></li><li><ahref="#impl-Value-for-NonZero%3Ci64%3E">NonZeroI64</a></li><li><ahref="#impl-Value-for-NonZero%3Ci8%3E">NonZeroI8</a></li><li><ahref="#impl-Value-for-NonZero%3Cisize%3E">NonZeroIsize</a></li><li><ahref="#impl-Value-for-NonZero%3Cu128%3E">NonZeroU128</a></li><li><ahref="#impl-Value-for-NonZero%3Cu16%3E">NonZeroU16</a></li><li><ahref="#impl-Value-for-NonZero%3Cu32%3E">NonZeroU32</a></li><li><ahref="#impl-Value-for-NonZero%3Cu64%3E">NonZeroU64</a></li><li><ahref="#impl-Value-for-NonZero%3Cu8%3E">NonZeroU8</a></li><li><ahref="#impl-Value-for-NonZero%3Cusize%3E">NonZeroUsize</a></li><li><ahref="#impl-Value-for-Option%3CT%3E">Option<T></a></li><li><ahref="#impl-Value-for-String">String</a></li><li><ahref="#impl-Value-for-Wrapping%3CT%3E">Wrapping<T></a></li><li><ahref="#impl-Value-for-bool">bool</a></li><li><ahref="#impl-Va
}</code></pre><detailsclass="toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>A field value of an erased type.</p>
<p>Implementors of <code>Value</code> may call the appropriate typed recording methods on
the <ahref="trait.Visit.html"title="trait tracing_core::field::Visit">visitor</a> passed to their <code>record</code> method in order to indicate how
their data should be recorded.</p>
</div></details><h2id="required-methods"class="section-header">Required Methods<ahref="#required-methods"class="anchor">§</a></h2><divclass="methods"><detailsclass="toggle method-toggle"open><summary><sectionid="tymethod.record"class="method"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#338">source</a><h4class="code-header">fn <ahref="#tymethod.record"class="fn">record</a>(&self, key: &<aclass="struct"href="../struct.Field.html"title="struct tracing_core::Field">Field</a>, visitor: &mut dyn <aclass="trait"href="trait.Visit.html"title="trait tracing_core::field::Visit">Visit</a>)</h4></section></summary><divclass="docblock"><p>Visits this value with the given <code>Visitor</code>.</p>
</div></details></div><h2id="trait-implementations"class="section-header">Trait Implementations<ahref="#trait-implementations"class="anchor">§</a></h2><divid="trait-implementations-list"><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Debug-for-dyn+Value"class="impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#638-665">source</a><ahref="#impl-Debug-for-dyn+Value"class="anchor">§</a><h3class="code-header">impl <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a> for dyn <aclass="trait"href="trait.Value.html"title="trait tracing_core::field::Value">Value</a></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.fmt-1"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#639-664">source</a><ahref="#method.fmt-1"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt"class="fn">fmt</a>(&self, f: &mut <aclass="struct"href="https://doc.rust-lang.org/1.80.0/core/fmt/struct.Formatter.html"title="struct core::fmt::Formatter">Formatter</a><'_>) -><aclass="type"href="https://doc.rust-lang.org/1.80.0/core/fmt/type.Result.html"title="type core::fmt::Result">Result</a></h4></section></summary><divclass='docblock'>Formats the value using the given formatter. <ahref="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Display-for-dyn+Value"class="impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#667-671">source</a><ahref="#impl-Display-for-dyn+Value"class="anchor">§</a><h3class="code-header">impl <aclass="trait"href="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html"title="trait core::fmt::Display">Display</a> for dyn <aclass="trait"href="trait.Value.html"title="trait tracing_core::field::Value">Value</a></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.fmt"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#668-670">source</a><ahref="#method.fmt"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html#tymethod.fmt"class="fn">fmt</a>(&self, f: &mut <aclass="struct"href="https://doc.rust-lang.org/1.80.0/core/fmt/struct.Formatter.html"title="struct core::fmt::Formatter">Formatter</a><'_>) -><aclass="type"href="https://doc.rust-lang.org/1.80.0/core/fmt/type.Result.html"title="type core::fmt::Result">Result</a></h4></section></summary><divclass='docblock'>Formats the value using the given formatter. <ahref="https://doc.rust-lang.org/1.80.0/core/fmt/trait.Display.html#tymethod.fmt">Read more</a></div></details></div></details></div><h2id="foreign-impls"class="section-header">Implementations on Foreign Types<ahref="#foreign-impls"class="anchor">§</a></h2><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-Value-for-bool"class="impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#517-526">source</a><ahref="#impl-Value-for-bool"class="anchor">§</a><h3class="code-header">impl <aclass="trait"href="trait.Value.html"title="trait tracing_core::field::Value">Value</a> for <aclass="primitive"href="https://doc.rust-lang.org/1.80.0/std/primitive.bool.html">bool</a></h3></section></summary><divclass="impl-items"><sectionid="method.record"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_core/field.rs.html#517-526">source</a><ahref="#method.record"class="anchor">§</a><h4class="code-header">fn <ahref="#tymethod.record"class="fn">record</a>(&self, key: &<aclass="struct"href="../struct.Field.html"title="struct tracing_core::Field">Fiel
