<noscript><linkrel="stylesheet"href="../../../noscript.css"></noscript><linkrel="alternate icon"type="image/png"href="../../../favicon-16x16.png"><linkrel="alternate icon"type="image/png"href="../../../favicon-32x32.png"><linkrel="icon"type="image/svg+xml"href="../../../favicon.svg"></head><bodyclass="rustdoc struct"><!--[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">☰</button><aclass="sidebar-logo"href="../../../actix_web_httpauth/index.html"><divclass="logo-container"><imgclass="rust-logo"src="../../../rust-logo.svg"alt="logo"></div>
</a><h2class="location"><ahref="#">BearerAuth</a></h2><divclass="sidebar-elems"><divclass="block items"><h3class="sidebar-title"><ahref="#implementations">Methods</a></h3><divclass="sidebar-links"><ahref="#method.token">token</a></div><h3class="sidebar-title"><ahref="#trait-implementations">Trait Implementations</a></h3><divclass="sidebar-links"><ahref="#impl-AuthExtractor">AuthExtractor</a><ahref="#impl-Clone">Clone</a><ahref="#impl-Debug">Debug</a><ahref="#impl-FromRequest">FromRequest</a></div><h3class="sidebar-title"><ahref="#synthetic-implementations">Auto Trait Implementations</a></h3><divclass="sidebar-links"><ahref="#impl-RefUnwindSafe">RefUnwindSafe</a><ahref="#impl-Send">Send</a><ahref="#impl-Sync">Sync</a><ahref="#impl-Unpin">Unpin</a><ahref="#impl-UnwindSafe">UnwindSafe</a></div><h3class="sidebar-title"><ahref="#blanket-implementations">Blanket Implementations</a></h3><divclass="sidebar-links"><ahref="#impl-Any">Any</a><ahref="#impl-Borrow%3CT%3E">Borrow<T></a><ahref="#impl-BorrowMut%3CT%3E">BorrowMut<T></a><ahref="#impl-From%3CT%3E">From<T></a><ahref="#impl-Instrument">Instrument</a><ahref="#impl-Into%3CU%3E">Into<U></a><ahref="#impl-Same%3CT%3E">Same<T></a><ahref="#impl-ToOwned">ToOwned</a><ahref="#impl-TryFrom%3CU%3E">TryFrom<U></a><ahref="#impl-TryInto%3CU%3E">TryInto<U></a><ahref="#impl-VZip%3CV%3E">VZip<V></a><ahref="#impl-WithSubscriber">WithSubscriber</a></div></div><h2class="location">In <ahref="../../index.html">actix_web_httpauth</a>::<wbr><ahref="../index.html">extractors</a>::<wbr><ahref="index.html">bearer</a></h2><divid="sidebar-vars"data-name="BearerAuth"data-ty="struct"data-relpath=""></div><scriptdefersrc="sidebar-items.js"></script></div></nav><main><divclass="width-limiter"><divclass="sub-container"><aclass="sub-logo-container"href="../../../actix_web_httpauth/index.html"><imgclass="rust-logo"src="../../../rust-logo.svg"alt="logo"></a><navclass="sub"><divclass="theme-picker hidden"><buttonid="theme-picker"aria-label="Pick another theme!"aria-haspopup="menu"title="themes"><imgwidth="22"height="22"alt="Pick another theme!"src="../../../brush.svg"></button><divid="theme-choices"role="menu"></div></div><formclass="search-form"><divclass="search-container"><span></span><inputclass="search-input"name="search"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><buttontype="button"id="help-button"title="help">?</button><aid="settings-menu"href="../../../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../../../wheel.svg"></a></div></form></nav></div><sectionid="main-content"class="content"><divclass="main-heading">
<spanclass="macro">format!</span>(<spanclass="string">"Hello, user with token {}!"</span>, <spanclass="ident">auth</span>.<spanclass="ident">token</span>())
</div></details></div></details><h2id="trait-implementations"class="small-section-header">Trait Implementations<ahref="#trait-implementations"class="anchor"></a></h2><divid="trait-implementations-list"><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-AuthExtractor"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#123-141"title="goto source code">source</a></div><ahref="#impl-AuthExtractor"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="../trait.AuthExtractor.html"title="trait actix_web_httpauth::extractors::AuthExtractor">AuthExtractor</a> for <aclass="struct"href="struct.BearerAuth.html"title="struct actix_web_httpauth::extractors::bearer::BearerAuth">BearerAuth</a></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Future-1"class="type trait-impl has-srclink"><ahref="#associatedtype.Future-1"class="anchor"></a><h4class="code-header">type <ahref="../trait.AuthExtractor.html#associatedtype.Future"class="associatedtype">Future</a> = Ready<<aclass="enum"href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html"title="enum core::result::Result">Result</a><Self, Self::<aclass="associatedtype"href="../trait.AuthExtractor.html#associatedtype.Error"title="type actix_web_httpauth::extractors::AuthExtractor::Error">Error</a>>></h4></div></summary><divclass='docblock'><p>Future that resolves into extracted credentials type.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Error-1"class="type trait-impl has-srclink"><ahref="#associatedtype.Error-1"class="anchor"></a><h4class="code-header">type <ahref="../trait.AuthExtractor.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="struct"href="../struct.AuthenticationError.html"title="struct actix_web_httpauth::extractors::AuthenticationError">AuthenticationError</a><<aclass="struct"href="../../headers/www_authenticate/bearer/struct.Bearer.html"title="struct actix_web_httpauth::headers::www_authenticate::bearer::Bearer">Bearer</a>></h4></div></summary><divclass='docblock'><p>The associated error which can be returned.</p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.from_service_request"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#127-140"title="goto source code">source</a></div><ahref="#method.from_service_request"class="anchor"></a><h4class="code-header">fn <ahref="../trait.AuthExtractor.html#tymethod.from_service_request"class="fnname">from_service_request</a>(req: &ServiceRequest) -> Self::<aclass="associatedtype"href="../trait.AuthExtractor.html#associatedtype.Future"title="type actix_web_httpauth::extractors::AuthExtractor::Future">Future</a></h4></div></summary><divclass='docblock'><p>Parse the authentication credentials from the actix’<code>ServiceRequest</code>.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-Clone"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#93"title="goto source code">source</a></div><ahref="#impl-Clone"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a> for <aclass="struct"href="struct.BearerAuth.html"title="struct actix_web_httpauth::extractors::bearer::BearerAuth">BearerAuth</a></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.clone"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#93"title="goto source code">source</a></div><ahref="#method.clone"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone"class="fnname">clone</a>(&self) -><aclass="struct"href="struct.BearerAuth.html"title="struct actix_web_httpauth::extractors::bearer::BearerAuth">BearerAuth</a></h4></div></summary><divclass='docblock'><p>Returns a copy of the value. <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone">Read more</a></p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.clone_from"class="method trait-impl has-srclink"><divclass="rightside"><spanclass="since"title="Stable since Rust version 1.0.0">1.0.0</span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/clone.rs.html#130"title="goto source code">source</a></div><ahref="#method.clone_from"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from"class="fnname">clone_from</a>(&mut self, source: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&</a>Self)</h4></div></summary><divclass='docblock'><p>Performs copy-assignment from <code>source</code>. <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from">Read more</a></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-Debug"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#93"title="goto source code">source</a></div><ahref="#impl-Debug"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a> for <aclass="struct"href="struct.BearerAuth.html"title="struct actix_web_httpauth::extractors::bearer::BearerAuth">BearerAuth</a></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.fmt"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#93"title="goto source code">source</a></div><ahref="#method.fmt"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt"class="fnname">fmt</a>(&self, f: &mut <aclass="struct"href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html"title="struct core::fmt::Formatter">Formatter</a><'_>) -><aclass="type"href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html"title="type core::fmt::Result">Result</a></h4></div></summary><divclass='docblock'><p>Formats the value using the given formatter. <ahref="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-FromRequest"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#103-121"title="goto source code">source</a></div><ahref="#impl-FromRequest"class="anchor"></a><h3class="code-header in-band">impl FromRequest for <aclass="struct"href="struct.BearerAuth.html"title="struct actix_web_httpauth::extractors::bearer::BearerAuth">BearerAuth</a></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Future"class="type trait-impl has-srclink"><ahref="#associatedtype.Future"class="anchor"></a><h4class="code-header">type <ahref="#associatedtype.Future"class="associatedtype">Future</a> = Ready<<aclass="enum"href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html"title="enum core::result::Result">Result</a><Self, Self::Error>></h4></div></summary><divclass='docblock'><p>Future that resolves to a Self.</p>
</div></details><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Error"class="type trait-impl has-srclink"><ahref="#associatedtype.Error"class="anchor"></a><h4class="code-header">type <ahref="#associatedtype.Error"class="associatedtype">Error</a> = <aclass="struct"href="../struct.AuthenticationError.html"title="struct actix_web_httpauth::extractors::AuthenticationError">AuthenticationError</a><<aclass="struct"href="../../headers/www_authenticate/bearer/struct.Bearer.html"title="struct actix_web_httpauth::headers::www_authenticate::bearer::Bearer">Bearer</a>></h4></div></summary><divclass='docblock'><p>The associated error which can be returned.</p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.from_request"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="../../../src/actix_web_httpauth/extractors/bearer.rs.html#107-120"title="goto source code">source</a></div><ahref="#method.from_request"class="anchor"></a><h4class="code-header">fn <aclass="fnname">from_request</a>(<br> req: &HttpRequest, <br> _payload: &mut Payload<br>) -><Self as FromRequest>::Future</h4></div></summary><divclass='docblock'><p>Create a Self from request parts asynchronously.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-Instrument"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://docs.rs/tracing/0.1.29/src/tracing/instrument.rs.html#276"title="goto source code">source</a></div><ahref="#impl-Instrument"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://docs.rs/tracing/0.1.29/tracing/instrument/trait.Instrument.html"title="trait tracing::instrument::Instrument">Instrument</a> for T</h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.instrument"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://docs.rs/tracing/0.1.29/src/tracing/instrument.rs.html#82"title="goto source code">source</a></div><ahref="#method.instrument"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.29/tracing/instrument/trait.Instrument.html#method.instrument"class="fnname">instrument</a>(self, span: <aclass="struct"href="https://docs.rs/tracing/0.1.29/tracing/span/struct.Span.html"title="struct tracing::span::Span">Span</a>) -><aclass="struct"href="https://docs.rs/tracing/0.1.29/tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></div></summary><divclass='docblock'><p>Instruments this type with the provided <ahref="https://docs.rs/tracing/0.1.29/tracing/span/struct.Span.html"title="Span"><code>Span</code></a>, returning an
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.in_current_span"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://docs.rs/tracing/0.1.29/src/tracing/instrument.rs.html#121"title="goto source code">source</a></div><ahref="#method.in_current_span"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.29/tracing/instrument/trait.Instrument.html#method.in_current_span"class="fnname">in_current_span</a>(self) -><aclass="struct"href="https://docs.rs/tracing/0.1.29/tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></div></summary><divclass='docblock'><p>Instruments this type with the <ahref="https://docs.rs/tracing/0.1.29/tracing/span/struct.Span.html#method.current">current</a><ahref="https://docs.rs/tracing/0.1.29/tracing/span/struct.Span.html"><code>Span</code></a>, returning an
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-Same%3CT%3E"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://docs.rs/typenum/1.15.0/src/typenum/type_operators.rs.html#34-36"title="goto source code">source</a></div><ahref="#impl-Same%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://docs.rs/typenum/1.15.0/typenum/type_operators/trait.Same.html"title="trait typenum::type_operators::Same">Same</a><T> for T</h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Output"class="type trait-impl has-srclink"><ahref="#associatedtype.Output"class="anchor"></a><h4class="code-header">type <ahref="https://docs.rs/typenum/1.15.0/typenum/type_operators/trait.Same.html#associatedtype.Output"class="associatedtype">Output</a> = T</h4></div></summary><divclass='docblock'><p>Should always be <code>Self</code></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-ToOwned"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#84-96"title="goto source code">source</a></div><ahref="#impl-ToOwned"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html"title="trait alloc::borrow::ToOwned">ToOwned</a> for T <spanclass="where fmt-newline">where<br> T: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a>, </span></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Owned"class="type trait-impl has-srclink"><ahref="#associatedtype.Owned"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#associatedtype.Owned"class="associatedtype">Owned</a> = T</h4></div></summary><divclass='docblock'><p>The resulting type after obtaining ownership.</p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.to_owned"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#89"title="goto source code">source</a></div><ahref="#method.to_owned"class="anchor"></a><h4class="code-header">pub fn <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#tymethod.to_owned"class="fnname">to_owned</a>(&self) -> T</h4></div></summary><divclass='docblock'><p>Creates owned data from borrowed data, usually by cloning. <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.clone_into"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#93"title="goto source code">source</a></div><ahref="#method.clone_into"class="anchor"></a><h4class="code-header">pub fn <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#method.clone_into"class="fnname">clone_into</a>(&self, target: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&mut </a>T)</h4></div></summary><divclass="item-info"><divclass="stab unstable"><spanclass="emoji">🔬</span> This is a nightly-only experimental API. (<code>toowned_clone_into</code>)</div></div><divclass='docblock'><p>Uses borrowed data to replace owned data, usually by cloning. <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-TryFrom%3CU%3E"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#589-598"title="goto source code">source</a></div><ahref="#impl-TryFrom%3CU%3E"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T <spanclass="where fmt-newline">where<br> U: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>, </span></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Error-3"class="type trait-impl has-srclink"><ahref="#associatedtype.Error-3"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/nightly/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></div></summary><divclass='docblock'><p>The type returned in the event of a conversion error.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><divid="impl-TryInto%3CU%3E"class="impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#574-583"title="goto source code">source</a></div><ahref="#impl-TryInto%3CU%3E"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T <spanclass="where fmt-newline">where<br> U: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>, </span></h3></div></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><divid="associatedtype.Error-2"class="type trait-impl has-srclink"><ahref="#associatedtype.Error-2"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></div></summary><divclass='docblock'><p>The type returned in the event of a conversion error.</p>
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><divid="method.with_current_subscriber"class="method trait-impl has-srclink"><divclass="rightside"><aclass="srclink"href="https://docs.rs/tracing/0.1.29/src/tracing/instrument.rs.html#221"title="goto source code">source</a></div><ahref="#method.with_current_subscriber"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.29/tracing/instrument/trait.WithSubscriber.html#method.with_current_subscriber"class="fnname">with_current_subscriber</a>(self) -><aclass="struct"href="https://docs.rs/tracing/0.1.29/tracing/instrument/struct.WithDispatch.html"title="struct tracing::instrument::WithDispatch">WithDispatch</a><Self></h4></div></summary><divclass='docblock'><p>Attaches the current <ahref="https://docs.rs/tracing/0.1.29/tracing/dispatcher/index.html#setting-the-default-subscriber">default</a><ahref="https://docs.rs/tracing-core/0.1.21/tracing_core/subscriber/trait.Subscriber.html"><code>Subscriber</code></a> to this type, returning a