<!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 `Layer` that logs formatted representations of `tracing` events."><title>Layer in tracing_subscriber::fmt - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2"><linkrel="stylesheet"href="../../static.files/normalize-76eba96aa4d2e634.css"><linkrel="stylesheet"href="../../static.files/rustdoc-5bc39a1768837dd0.css"><metaname="rustdoc-vars"data-root-path="../../"data-static-root-path="../../static.files/"data-current-crate="tracing_subscriber"data-themes=""data-resource-suffix=""data-rustdoc-version="1.77.2 (25ef9e3d8 2024-04-09)"data-channel="1.77.2"data-search-js="search-dd67cee4cfa65049.js"data-settings-js="settings-4313503d2e1961c2.js"><scriptsrc="../../static.files/storage-4c98445ec4002617.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../../static.files/main-48f368f3872407c8.js"></script><noscript><linkrel="stylesheet"href="../../static.files/noscript-04d5337699b92874.css"></noscript><linkrel="alternate icon"type="image/png"href="../../static.files/favicon-16x16-8b506e7a72182f1c.png"><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 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"title="show sidebar"></button><aclass="logo-container"href="../../tracing_subscriber/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_subscriber/index.html"><imgsrc="https://raw.githubusercontent.com/tokio-rs/tracing/master/assets/logo-type.png"alt="logo"></a><h2><ahref="../../tracing_subscriber/index.html">tracing_subscriber</a><spanclass="version">0.3.18</span></h2></div><h2class="location"><ahref="#">Layer</a></h2><divclass="sidebar-elems"><section><h3><ahref="#implementations">Methods</a></h3><ulclass="block method"><li><ahref="#method.compact">compact</a></li><li><ahref="#method.event_format">event_format</a></li><li><ahref="#method.fmt_fields">fmt_fields</a></li><li><ahref="#method.log_internal_errors">log_internal_errors</a></li><li><ahref="#method.map_event_format">map_event_format</a></li><li><ahref="#method.map_fmt_fields">map_fmt_fields</a></li><li><ahref="#method.map_writer">map_writer</a></li><li><ahref="#method.new">new</a></li><li><ahref="#method.pretty">pretty</a></li><li><ahref="#method.set_ansi">set_ansi</a></li><li><ahref="#method.with_ansi">with_ansi</a></li><li><ahref="#method.with_file">with_file</a></li><li><ahref="#method.with_level">with_level</a></li><li><ahref="#method.with_line_number">with_line_number</a></li><li><ahref="#method.with_span_events">with_span_events</a></li><li><ahref="#method.with_target">with_target</a></li><li><ahref="#method.with_test_writer">with_test_writer</a></li><li><ahref="#method.with_thread_ids">with_thread_ids</a></li><li><ahref="#method.with_thread_names">with_thread_names</a></li><li><ahref="#method.with_timer">w
<main><divclass="width-limiter"><navclass="sub"><formclass="search-form"><span></span><divid="sidebar-button"tabindex="-1"><ahref="../../tracing_subscriber/all.html"title="show sidebar"></a></div><inputclass="search-input"name="search"aria-label="Run search in the documentation"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"tabindex="-1"><ahref="../../help.html"title="help">?</a></div><divid="settings-menu"tabindex="-1"><ahref="../../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><sectionid="main-content"class="content"><divclass="main-heading"><h1>Struct <ahref="../index.html">tracing_subscriber</a>::<wbr><ahref="index.html">fmt</a>::<wbr><aclass="struct"href="#">Layer</a><buttonid="copy-path"title="Copy item path to clipboard"><imgsrc="../../static.files/clipboard-7571035ce49a181d.svg"width="19"height="18"alt="Copy item path"></button></h1><spanclass="out-of-band"><aclass="src"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#64-77">source</a> · <buttonid="toggle-all-docs"title="collapse all docs">[<span>−</span>]</button></span></div><preclass="rust item-decl"><code>pub struct Layer<S, N = <aclass="struct"href="format/struct.DefaultFields.html"title="struct tracing_subscriber::fmt::format::DefaultFields">DefaultFields</a>, E = <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><<aclass="struct"href="format/struct.Full.html"title="struct tracing_subscriber::fmt::format::Full">Full</a>>, W = <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.fn.html">fn</a>() -><aclass="struct"href="https://doc.rust-lang.org/1.77.2/std/io/stdio/struct.Stdout.html"title="struct std::io::stdio::Stdout">Stdout</a>> { <spanclass="comment">/* private fields */</span> }</code></pre><detailsclass="toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>A <ahref="../layer/trait.Layer.html"title="trait tracing_subscriber::layer::Layer"><code>Layer</code></a> that logs formatted representations of <code>tracing</code> events.</p>
<divclass="example-wrap"><preclass="rust rust-example-rendered"><code><spanclass="kw">use </span>tracing_subscriber::fmt::{<spanclass="self">self</span>, format, time};
</div></details><h2id="implementations"class="section-header">Implementations<ahref="#implementations"class="anchor">§</a></h2><divid="implementations-list"><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#79-84">source</a><ahref="#impl-Layer%3CS%3E"class="anchor">§</a><h3class="code-header">impl<S><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.new"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#81-83">source</a><h4class="code-header">pub fn <ahref="#method.new"class="fn">new</a>() -> Self</h4></section></summary><divclass="docblock"><p>Returns a new <ahref="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer"><code>Layer</code></a> with the default configuration.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS,+N,+E,+W%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#87-159">source</a><ahref="#impl-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
E2: <aclass="trait"href="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent">FormatEvent</a><S, N> + 'static,</div></h4></section></summary><divclass="docblock"><p>Sets the <ahref="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent">event formatter</a> that the layer being built will
use to format events.</p>
<p>The event formatter may be any type implementing the <ahref="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent"><code>FormatEvent</code></a>
trait, which is implemented for all functions taking a <ahref="struct.FmtContext.html"title="struct tracing_subscriber::fmt::FmtContext"><code>FmtContext</code></a>, a
<ahref="format/struct.Writer.html"title="struct tracing_subscriber::fmt::format::Writer"><code>Writer</code></a>, and an <ahref="../../tracing_core/event/struct.Event.html"title="struct tracing_core::event::Event"><code>Event</code></a>.</p>
<p>Setting a type implementing <ahref="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent"><code>FormatEvent</code></a> as the formatter:</p>
E2: <aclass="trait"href="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent">FormatEvent</a><S, N> + 'static,</div></h4></section></summary><divclass="docblock"><p>Updates the event formatter by applying a function to the existing event formatter.</p>
<p>This sets the event formatter that the layer being built will use to record fields.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS,+N,+E,+W%3E-1"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#162-373">source</a><ahref="#impl-Layer%3CS,+N,+E,+W%3E-1"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_writer"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#179-192">source</a><h4class="code-header">pub fn <ahref="#method.with_writer"class="fn">with_writer</a><W2>(self, make_writer: W2) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W2><divclass="where">where
W2: for<'writer><aclass="trait"href="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter">MakeWriter</a><'writer> + 'static,</div></h4></section></summary><divclass="docblock"><p>Sets the <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter"><code>MakeWriter</code></a> that the layer being built will use to write events.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.writer"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#197-199">source</a><h4class="code-header">pub fn <ahref="#method.writer"class="fn">writer</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.reference.html">&W</a></h4></section></summary><divclass="docblock"><p>Borrows the <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter">writer</a> for this <ahref="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer"><code>Layer</code></a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.writer_mut"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#228-230">source</a><h4class="code-header">pub fn <ahref="#method.writer_mut"class="fn">writer_mut</a>(&mut self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.reference.html">&mut W</a></h4></section></summary><divclass="docblock"><p>Mutably borrows the <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter">writer</a> for this <ahref="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer"><code>Layer</code></a>.</p>
<p>This method is primarily expected to be used with the
<ahref="../reload/struct.Handle.html#method.modify"title="method tracing_subscriber::reload::Handle::modify"><code>reload::Handle::modify</code></a> method when changing
the writer.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_test_writer"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#266-276">source</a><h4class="code-header">pub fn <ahref="#method.with_test_writer"class="fn">with_test_writer</a>(self) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, <aclass="struct"href="struct.TestWriter.html"title="struct tracing_subscriber::fmt::TestWriter">TestWriter</a>></h4></section></summary><divclass="docblock"><p>Configures the layer to support <ahref="https://doc.rust-lang.org/book/ch11-02-running-tests.html#showing-function-output"><code>libtest</code>’s output capturing</a> when used in
unit tests.</p>
<p>See <ahref="struct.TestWriter.html"title="struct tracing_subscriber::fmt::TestWriter"><code>TestWriter</code></a> for additional details.</p>
<p>Using <ahref="struct.TestWriter.html"title="struct tracing_subscriber::fmt::TestWriter"><code>TestWriter</code></a> to let <code>cargo test</code> capture test output:</p>
<p>When the “ansi” crate feature flag is enabled, ANSI colors are enabled
by default unless the <ahref="https://no-color.org/"><code>NO_COLOR</code></a> environment variable is set to
a non-empty value. If the <ahref="https://no-color.org/"><code>NO_COLOR</code></a> environment variable is set to
any non-empty value, then ANSI colors will be suppressed by default.
The <ahref="Subscriber::with_ansi"><code>with_ansi</code></a> and <ahref="Subscriber::set_ansi"><code>set_ansi</code></a> methods can be used to forcibly
enable ANSI colors, overriding any <ahref="https://no-color.org/"><code>NO_COLOR</code></a> environment variable.</p>
<p>Enabling ANSI escapes (calling <code>with_ansi(true)</code>) requires the “ansi”
crate feature flag. Calling <code>with_ansi(true)</code> without the “ansi”
feature flag enabled will panic if debug assertions are enabled, or
print a warning otherwise.</p>
<p>This method itself is still available without the feature flag. This
is to allow ANSI escape codes to be explicitly <em>disabled</em> without
having to opt-in to the dependencies required to emit ANSI formatting.
This way, code which constructs a formatter that should never emit
ANSI escape codes can ensure that they are not used, regardless of
whether or not other crates in the dependency graph enable the “ansi”
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.log_internal_errors"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#333-338">source</a><h4class="code-header">pub fn <ahref="#method.log_internal_errors"class="fn">log_internal_errors</a>(self, log_internal_errors: <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a>) -> Self</h4></section></summary><divclass="docblock"><p>Sets whether to write errors from <ahref="trait.FormatEvent.html"title="trait tracing_subscriber::fmt::FormatEvent"><code>FormatEvent</code></a> to the writer.
W2: for<'writer><aclass="trait"href="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter">MakeWriter</a><'writer> + 'static,</div></h4></section></summary><divclass="docblock"><p>Updates the <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter"><code>MakeWriter</code></a> by applying a function to the existing <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter"><code>MakeWriter</code></a>.</p>
<p>This sets the <ahref="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter"><code>MakeWriter</code></a> that the layer being built will use to write events.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS,+N,+Format%3CL,+T%3E,+W%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#375-592">source</a><ahref="#impl-Layer%3CS,+N,+Format%3CL,+T%3E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, L, T, W><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W><divclass="where">where
N: for<'writer><aclass="trait"href="trait.FormatFields.html"title="trait tracing_subscriber::fmt::FormatFields">FormatFields</a><'writer> + 'static,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_timer"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#393-403">source</a><h4class="code-header">pub fn <ahref="#method.with_timer"class="fn">with_timer</a><T2>(self, timer: T2) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T2>, W></h4></section></summary><divclass="docblock"><p>Use the given <ahref="time/trait.FormatTime.html"title="trait tracing_subscriber::fmt::time::FormatTime"><code>timer</code></a> for span and event timestamps.</p>
<p>See the <ahref="time/index.html"title="mod tracing_subscriber::fmt::time"><code>time</code> module</a> for the provided timer implementations.</p>
<p>Note that using the <code>"time</code>“” feature flag enables the
additional time formatters <ahref="super::time::UtcTime"><code>UtcTime</code></a> and <ahref="super::time::LocalTime"><code>LocalTime</code></a>, which use the
<ahref="https://docs.rs/time/0.3"><code>time</code> crate</a> to provide more sophisticated timestamp formatting
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.without_time"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#406-416">source</a><h4class="code-header">pub fn <ahref="#method.without_time"class="fn">without_time</a>(self) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.unit.html">()</a>>, W></h4></section></summary><divclass="docblock"><p>Do not emit timestamps with spans and event.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_span_events"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#459-464">source</a><h4class="code-header">pub fn <ahref="#method.with_span_events"class="fn">with_span_events</a>(self, kind: <aclass="struct"href="format/struct.FmtSpan.html"title="struct tracing_subscriber::fmt::format::FmtSpan">FmtSpan</a>) -> Self</h4></section></summary><divclass="docblock"><p>Configures how synthesized events are emitted at points in the <ahref="https://docs.rs/tracing/latest/tracing/span/index.html#the-span-lifecycle">span
lifecycle</a>.</p>
<p>The following options are available:</p>
<ul>
<li><code>FmtSpan::NONE</code>: No events will be synthesized when spans are
created, entered, exited, or closed. Data from spans will still be
included as the context for formatted events. This is the default.</li>
<li><code>FmtSpan::NEW</code>: An event will be synthesized when spans are created.</li>
<li><code>FmtSpan::ENTER</code>: An event will be synthesized when spans are entered.</li>
<li><code>FmtSpan::EXIT</code>: An event will be synthesized when spans are exited.</li>
<li><code>FmtSpan::CLOSE</code>: An event will be synthesized when a span closes. If
<ahref="struct.Layer.html#method.without_time"title="method tracing_subscriber::fmt::Layer::without_time">timestamps are enabled</a> for this formatter, the generated
event will contain fields with the span’s <em>busy time</em> (the total
time for which it was entered) and <em>idle time</em> (the total time that
the span existed but was not entered).</li>
<li><code>FmtSpan::ACTIVE</code>: Events will be synthesized when spans are entered
or exited.</li>
<li><code>FmtSpan::FULL</code>: Events will be synthesized whenever a span is
created, entered, exited, or closed. If timestamps are enabled, the
close event will contain the span’s busy and idle time, as
described above.</li>
</ul>
<p>The options can be enabled in any combination. For instance, the following
will synthesize events whenever spans are created and closed:</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_target"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#467-472">source</a><h4class="code-header">pub fn <ahref="#method.with_target"class="fn">with_target</a>(self, display_target: <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a>) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not an event’s target is displayed.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_file"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#477-482">source</a><h4class="code-header">pub fn <ahref="#method.with_file"class="fn">with_file</a>(self, display_filename: <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a>) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not an event’s <ahref="../../tracing_core/metadata/struct.Metadata.html#method.file"title="method tracing_core::metadata::Metadata::file">source code file path</a> is
) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not an event’s <ahref="../../tracing_core/metadata/struct.Metadata.html#method.line"title="method tracing_core::metadata::Metadata::line">source code line number</a> is
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_level"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#499-504">source</a><h4class="code-header">pub fn <ahref="#method.with_level"class="fn">with_level</a>(self, display_level: <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a>) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not an event’s level is displayed.</p>
) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not the <ahref="https://doc.rust-lang.org/1.77.2/std/thread/struct.ThreadId.html"title="struct std::thread::ThreadId">thread ID</a> of the current thread is displayed
) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><L, T>, W></h4></section></summary><divclass="docblock"><p>Sets whether or not the <ahref="https://doc.rust-lang.org/1.77.2/std/thread/index.html#naming-threads"title="mod std::thread">name</a> of the current thread is displayed
N: for<'writer><aclass="trait"href="trait.FormatFields.html"title="trait tracing_subscriber::fmt::FormatFields">FormatFields</a><'writer> + 'static,</div></h4></section></summary><divclass="docblock"><p>Sets the layer being built to use a <ahref="format/struct.Compact.html"title="struct tracing_subscriber::fmt::format::Compact">less verbose formatter</a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.pretty"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#550-560">source</a><h4class="code-header">pub fn <ahref="#method.pretty"class="fn">pretty</a>(self) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, <aclass="struct"href="format/struct.Pretty.html"title="struct tracing_subscriber::fmt::format::Pretty">Pretty</a>, <aclass="struct"href="format/struct.Format.html"title="struct tracing_subscriber::fmt::format::Format">Format</a><<aclass="struct"href="format/struct.Pretty.html"title="struct tracing_subscriber::fmt::format::Pretty">Pretty</a>, T>, W></h4></section></summary><divclass="docblock"><p>Sets the layer being built to use an <ahref="format/struct.Pretty.html"title="struct tracing_subscriber::fmt::format::Pretty">excessively pretty, human-readable formatter</a>.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS,+N,+E,+W%3E-2"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#642-690">source</a><ahref="#impl-Layer%3CS,+N,+E,+W%3E-2"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.fmt_fields"class="method"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#645-658">source</a><h4class="code-header">pub fn <ahref="#method.fmt_fields"class="fn">fmt_fields</a><N2>(self, fmt_fields: N2) -><aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N2, E, W><divclass="where">where
N2: for<'writer><aclass="trait"href="trait.FormatFields.html"title="trait tracing_subscriber::fmt::FormatFields">FormatFields</a><'writer> + 'static,</div></h4></section></summary><divclass="docblock"><p>Sets the field formatter that the layer being built will use to record
N2: for<'writer><aclass="trait"href="trait.FormatFields.html"title="trait tracing_subscriber::fmt::FormatFields">FormatFields</a><'writer> + 'static,</div></h4></section></summary><divclass="docblock"><p>Updates the field formatter by applying a function to the existing field formatter.</p>
<p>This sets the field formatter that the layer being built will use to record fields.</p>
</div></details></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-Layer%3CS,+N,+E,+W%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#63">source</a><ahref="#impl-Debug-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a>, N: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a>, E: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a>, W: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a>><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W></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_subscriber/fmt/fmt_layer.rs.html#63">source</a><ahref="#method.fmt"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.2/core/fmt/trait.Debug.html#tymethod.fmt"class="fn">fmt</a>(&self, f: &mut <aclass="struct"href="https://doc.rust-lang.org/1.77.2/core/fmt/struct.Formatter.html"title="struct core::fmt::Formatter">Formatter</a><'_>) -><aclass="type"href="https://doc.rust-lang.org/1.77.2/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/1.77.2/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Default-for-Layer%3CS%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#692-708">source</a><ahref="#impl-Default-for-Layer%3CS%3E"class="anchor">§</a><h3class="code-header">impl<S><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/default/trait.Default.html"title="trait core::default::Default">Default</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.default"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#693-707">source</a><ahref="#method.default"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.2/core/default/trait.Default.html#tymethod.default"class="fn">default</a>() -> Self</h4></section></summary><divclass='docblock'>Returns the “default value” for a type. <ahref="https://doc.rust-lang.org/1.77.2/core/default/trait.Default.html#tymethod.default">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Layer%3CS%3E-for-Layer%3CS,+N,+E,+W%3E"class="impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#804-1008">source</a><ahref="#impl-Layer%3CS%3E-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="../layer/trait.Layer.html"title="trait tracing_subscriber::layer::Layer">Layer</a><S> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
W: for<'writer><aclass="trait"href="trait.MakeWriter.html"title="trait tracing_subscriber::fmt::MakeWriter">MakeWriter</a><'writer> + 'static,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_new_span"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#811-846">source</a><ahref="#method.on_new_span"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_new_span"class="fn">on_new_span</a>(&self, attrs: &<aclass="struct"href="../../tracing_core/span/struct.Attributes.html"title="struct tracing_core::span::Attributes">Attributes</a><'_>, id: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that a new span was constructed with the given
<code>Attributes</code> and <code>Id</code>.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_record"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#848-865">source</a><ahref="#method.on_record"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_record"class="fn">on_record</a>(&self, id: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, values: &<aclass="struct"href="../../tracing_core/span/struct.Record.html"title="struct tracing_core::span::Record">Record</a><'_>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that a span with the given <code>Id</code> recorded the given
<code>values</code>.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_enter"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#867-885">source</a><ahref="#method.on_enter"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_enter"class="fn">on_enter</a>(&self, id: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that a span with the given ID was entered.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_exit"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#887-905">source</a><ahref="#method.on_exit"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_exit"class="fn">on_exit</a>(&self, id: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that the span with the given ID was exited.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_close"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#907-942">source</a><ahref="#method.on_close"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_close"class="fn">on_close</a>(&self, id: <aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that the span with the given ID has been closed.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_event"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/fmt/fmt_layer.rs.html#944-993">source</a><ahref="#method.on_event"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_event"class="fn">on_event</a>(&self, event: &<aclass="struct"href="../../tracing_core/event/struct.Event.html"title="struct tracing_core::event::Event">Event</a><'_>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that an event has occurred.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_register_dispatch"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#753-755">source</a><ahref="#method.on_register_dispatch"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_register_dispatch"class="fn">on_register_dispatch</a>(&self, subscriber: &<aclass="struct"href="../../tracing_core/dispatcher/struct.Dispatch.html"title="struct tracing_core::dispatcher::Dispatch">Dispatch</a>)</h4></section></summary><divclass='docblock'>Performs late initialization when installing this layer as a
<ahref="../../tracing_core/subscriber/trait.Subscriber.html"title="trait tracing_core::subscriber::Subscriber"><code>Subscriber</code></a>. <ahref="../layer/trait.Layer.html#method.on_register_dispatch">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_layer"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#784-786">source</a><ahref="#method.on_layer"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_layer"class="fn">on_layer</a>(&mut self, subscriber: <aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.reference.html">&mut S</a>)</h4></section></summary><divclass='docblock'>Performs late initialization when attaching a <code>Layer</code> to a
<ahref="../../tracing_core/subscriber/trait.Subscriber.html"title="trait tracing_core::subscriber::Subscriber"><code>Subscriber</code></a>. <ahref="../layer/trait.Layer.html#method.on_layer">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.register_callsite"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#828-834">source</a><ahref="#method.register_callsite"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.register_callsite"class="fn">register_callsite</a>(&self, metadata: &'static <aclass="struct"href="../../tracing_core/metadata/struct.Metadata.html"title="struct tracing_core::metadata::Metadata">Metadata</a><'static>) -><aclass="struct"href="../../tracing_core/subscriber/struct.Interest.html"title="struct tracing_core::subscriber::Interest">Interest</a></h4></section></summary><divclass='docblock'>Registers a new callsite with this layer, returning whether or not
the layer is interested in being notified about the callsite, similarly
to <ahref="../../tracing_core/subscriber/trait.Subscriber.html#method.register_callsite"title="method tracing_core::subscriber::Subscriber::register_callsite"><code>Subscriber::register_callsite</code></a>. <ahref="../layer/trait.Layer.html#method.register_callsite">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.enabled"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#868-871">source</a><ahref="#method.enabled"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.enabled"class="fn">enabled</a>(&self, metadata: &<aclass="struct"href="../../tracing_core/metadata/struct.Metadata.html"title="struct tracing_core::metadata::Metadata">Metadata</a><'_>, ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>Returns <code>true</code> if this layer is interested in a span or event with the
given <code>metadata</code> in the current <ahref="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context"><code>Context</code></a>, similarly to
<ahref="../../tracing_core/subscriber/trait.Subscriber.html#tymethod.enabled"title="method tracing_core::subscriber::Subscriber::enabled"><code>Subscriber::enabled</code></a>. <ahref="../layer/trait.Layer.html#method.enabled">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_follows_from"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#899">source</a><ahref="#method.on_follows_from"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_follows_from"class="fn">on_follows_from</a>(&self, _span: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, _follows: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, _ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that a span with the ID <code>span</code> recorded that it
follows from the span with the ID <code>follows</code>.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.event_enabled"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#922-924">source</a><ahref="#method.event_enabled"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.event_enabled"class="fn">event_enabled</a>(&self, _event: &<aclass="struct"href="../../tracing_core/event/struct.Event.html"title="struct tracing_core::event::Event">Event</a><'_>, _ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.2/std/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>Called before <ahref="../layer/trait.Layer.html#method.on_event"><code>on_event</code></a>, to determine if <code>on_event</code> should be called.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.on_id_change"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#940">source</a><ahref="#method.on_id_change"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.on_id_change"class="fn">on_id_change</a>(&self, _old: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, _new: &<aclass="struct"href="../../tracing_core/span/struct.Id.html"title="struct tracing_core::span::Id">Id</a>, _ctx: <aclass="struct"href="../layer/struct.Context.html"title="struct tracing_subscriber::layer::Context">Context</a><'_, S>)</h4></section></summary><divclass='docblock'>Notifies this layer that a span ID has been cloned, and that the
subscriber returned a different ID.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.and_then"class="method trait-impl"><aclass="src rightside"href="../../src/tracing_subscriber/layer/mod.rs.html#1039-1046">source</a><ahref="#method.and_then"class="anchor">§</a><h4class="code-header">fn <ahref="../layer/trait.Layer.html#method.and_then"class="fn">and_then</a><L>(self, layer: L) -><aclass="struct"href="../layer/struct.Layered.html"title="struct tracing_subscriber::layer::Layered">Layered</a><L, Self, S><divclass="where">where
Self: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass='docblock'>Composes this layer around the given <code>Layer</code>, returning a <code>Layered</code>
Self: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>,</div></h4></section></summary><divclass='docblock'>Composes this <code>Layer</code> with the given <ahref="../../tracing_core/subscriber/trait.Subscriber.html"title="trait tracing_core::subscriber::Subscriber"><code>Subscriber</code></a>, returning a
F: <aclass="trait"href="../layer/trait.Filter.html"title="trait tracing_subscriber::layer::Filter">Filter</a><S>,</div></h4></section></summary><divclass='docblock'>Combines <code>self</code> with a <ahref="../layer/trait.Filter.html"title="trait tracing_subscriber::layer::Filter"><code>Filter</code></a>, returning a <ahref="../filter/struct.Filtered.html"title="struct tracing_subscriber::filter::Filtered"><code>Filtered</code></a> layer. <ahref="../layer/trait.Layer.html#method.with_filter">Read more</a></div></details></div></details></div><h2id="synthetic-implementations"class="section-header">Auto Trait Implementations<ahref="#synthetic-implementations"class="anchor">§</a></h2><divid="synthetic-implementations-list"><sectionid="impl-RefUnwindSafe-for-Layer%3CS,+N,+E,+W%3E"class="impl"><ahref="#impl-RefUnwindSafe-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/panic/unwind_safe/trait.RefUnwindSafe.html"title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
W: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/panic/unwind_safe/trait.RefUnwindSafe.html"title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,</div></h3></section><sectionid="impl-Send-for-Layer%3CS,+N,+E,+W%3E"class="impl"><ahref="#impl-Send-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
W: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a>,</div></h3></section><sectionid="impl-Sync-for-Layer%3CS,+N,+E,+W%3E"class="impl"><ahref="#impl-Sync-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Sync.html"title="trait core::marker::Sync">Sync</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
W: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Sync.html"title="trait core::marker::Sync">Sync</a>,</div></h3></section><sectionid="impl-Unpin-for-Layer%3CS,+N,+E,+W%3E"class="impl"><ahref="#impl-Unpin-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Unpin.html"title="trait core::marker::Unpin">Unpin</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
W: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/marker/trait.Unpin.html"title="trait core::marker::Unpin">Unpin</a>,</div></h3></section><sectionid="impl-UnwindSafe-for-Layer%3CS,+N,+E,+W%3E"class="impl"><ahref="#impl-UnwindSafe-for-Layer%3CS,+N,+E,+W%3E"class="anchor">§</a><h3class="code-header">impl<S, N, E, W><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/panic/unwind_safe/trait.UnwindSafe.html"title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <aclass="struct"href="struct.Layer.html"title="struct tracing_subscriber::fmt::Layer">Layer</a><S, N, E, W><divclass="where">where
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-Instrument-for-T"class="impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#325">source</a><ahref="#impl-Instrument-for-T"class="anchor">§</a><h3class="code-header">impl<T><aclass="trait"href="../../tracing/instrument/trait.Instrument.html"title="trait tracing::instrument::Instrument">Instrument</a> for T</h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.instrument"class="method trait-impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#86">source</a><ahref="#method.instrument"class="anchor">§</a><h4class="code-header">fn <ahref="../../tracing/instrument/trait.Instrument.html#method.instrument"class="fn">instrument</a>(self, span: <aclass="struct"href="../../tracing/span/struct.Span.html"title="struct tracing::span::Span">Span</a>) -><aclass="struct"href="../../tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></section></summary><divclass='docblock'>Instruments this type with the provided <ahref="../../tracing/span/struct.Span.html"title="struct tracing::span::Span"><code>Span</code></a>, returning an
<code>Instrumented</code> wrapper. <ahref="../../tracing/instrument/trait.Instrument.html#method.instrument">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.in_current_span"class="method trait-impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#128">source</a><ahref="#method.in_current_span"class="anchor">§</a><h4class="code-header">fn <ahref="../../tracing/instrument/trait.Instrument.html#method.in_current_span"class="fn">in_current_span</a>(self) -><aclass="struct"href="../../tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></section></summary><divclass='docblock'>Instruments this type with the <ahref="../../tracing/span/struct.Span.html#method.current"title="associated function tracing::span::Span::current">current</a><ahref="../../tracing/span/struct.Span.html"title="struct tracing::span::Span"><code>Span</code></a>, returning an
<code><ahref="https://doc.rust-lang.org/1.77.2/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.2/src/core/convert/mod.rs.html#804-806">source</a><ahref="#impl-TryFrom%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error-1"class="associatedtype trait-impl"><ahref="#associatedtype.Error-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/1.77.2/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_from"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.2/src/core/convert/mod.rs.html#811">source</a><ahref="#method.try_from"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html#tymethod.try_from"class="fn">try_from</a>(value: U) -><aclass="enum"href="https://doc.rust-lang.org/1.77.2/core/result/enum.Result.html"title="enum core::result::Result">Result</a><T, <T as <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryInto%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.2/src/core/convert/mod.rs.html#789-791">source</a><ahref="#impl-TryInto%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error"class="associatedtype trait-impl"><ahref="#associatedtype.Error"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.2/src/core/convert/mod.rs.html#796">source</a><ahref="#method.try_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryInto.html#tymethod.try_into"class="fn">try_into</a>(self) -><aclass="enum"href="https://doc.rust-lang.org/1.77.2/core/result/enum.Result.html"title="enum core::result::Result">Result</a><U, <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-WithSubscriber-for-T"class="impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#393">source</a><ahref="#impl-WithSubscriber-for-T"class="anchor">§</a><h3class="code-header">impl<T><aclass="trait"href="../../tracing/instrument/trait.WithSubscriber.html"title="trait tracing::instrument::WithSubscriber">WithSubscriber</a> for T</h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_subscriber-1"class="method trait-impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#176-178">source</a><ahref="#method.with_subscriber-1"class="anchor">§</a><h4class="code-header">fn <ahref="../../tracing/instrument/trait.WithSubscriber.html#method.with_subscriber"class="fn">with_subscriber</a><S>(self, subscriber: S) -><aclass="struct"href="../../tracing/instrument/struct.WithDispatch.html"title="struct tracing::instrument::WithDispatch">WithDispatch</a><Self><divclass="where">where
S: <aclass="trait"href="https://doc.rust-lang.org/1.77.2/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><<aclass="struct"href="../../tracing_core/dispatcher/struct.Dispatch.html"title="struct tracing_core::dispatcher::Dispatch">Dispatch</a>>,</div></h4></section></summary><divclass='docblock'>Attaches the provided <ahref="../../tracing_core/subscriber/trait.Subscriber.html"title="trait tracing_core::subscriber::Subscriber"><code>Subscriber</code></a> to this type, returning a
<ahref="../../tracing/instrument/struct.WithDispatch.html"title="struct tracing::instrument::WithDispatch"><code>WithDispatch</code></a> wrapper. <ahref="../../tracing/instrument/trait.WithSubscriber.html#method.with_subscriber">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.with_current_subscriber"class="method trait-impl"><aclass="src rightside"href="../../src/tracing/instrument.rs.html#228">source</a><ahref="#method.with_current_subscriber"class="anchor">§</a><h4class="code-header">fn <ahref="../../tracing/instrument/trait.WithSubscriber.html#method.with_current_subscriber"class="fn">with_current_subscriber</a>(self) -><aclass="struct"href="../../tracing/instrument/struct.WithDispatch.html"title="struct tracing::instrument::WithDispatch">WithDispatch</a><Self></h4></section></summary><divclass='docblock'>Attaches the current <ahref="../../tracing/dispatcher/index.html#setting-the-default-subscriber"title="mod tracing::dispatcher">default</a><ahref="../../tracing_core/subscriber/trait.Subscriber.html"title="trait tracing_core::subscriber::Subscriber"><code>Subscriber</code></a> to this type, returning a