<p><ahref="https://crates.io/crates/tracing"><code>tracing</code></a> is a framework for instrumenting Rust programs to collect
structured, event-based diagnostic information. This crate defines the core
primitives of <code>tracing</code>.</p>
<p>This crate provides:</p>
<ul>
<li>
<p><ahref="span/struct.Id.html"title="struct tracing_core::span::Id"><code>span::Id</code></a> identifies a span within the execution of a program.</p>
</li>
<li>
<p><ahref="struct.Event.html"title="struct tracing_core::Event"><code>Event</code></a> represents a single event within a trace.</p>
</li>
<li>
<p><ahref="trait.Subscriber.html"title="trait tracing_core::Subscriber"><code>Subscriber</code></a>, the trait implemented to collect trace data.</p>
</li>
<li>
<p><ahref="struct.Metadata.html"title="struct tracing_core::Metadata"><code>Metadata</code></a> and <ahref="trait.Callsite.html"title="trait tracing_core::Callsite"><code>Callsite</code></a> provide information describing spans and
<code>Event</code>s.</p>
</li>
<li>
<p><ahref="struct.Field.html"title="struct tracing_core::Field"><code>Field</code></a>, <ahref="field/struct.FieldSet.html"title="struct tracing_core::field::FieldSet"><code>FieldSet</code></a>, <ahref="field/trait.Value.html"title="trait tracing_core::field::Value"><code>Value</code></a>, and <ahref="field/struct.ValueSet.html"title="struct tracing_core::field::ValueSet"><code>ValueSet</code></a> represent the
structured data attached to a span.</p>
</li>
<li>
<p><ahref="struct.Dispatch.html"title="struct tracing_core::Dispatch"><code>Dispatch</code></a> allows spans and events to be dispatched to <code>Subscriber</code>s.</p>
</li>
</ul>
<p>In addition, it defines the global callsite registry and per-thread current
dispatcher which other components of the tracing system rely on.</p>
</div></details><h2id="reexports"class="section-header">Re-exports<ahref="#reexports"class="anchor">§</a></h2><ulclass="item-table"><li><divclass="item-name"id="reexport.Kind"><code>pub use self::metadata::<aclass="struct"href="metadata/struct.Kind.html"title="struct tracing_core::metadata::Kind">Kind</a>;</code></div></li><li><divclass="item-name"id="reexport.Interest"><code>pub use self::subscriber::<aclass="struct"href="subscriber/struct.Interest.html"title="struct tracing_core::subscriber::Interest">Interest</a>;</code></div></li></ul><h2id="modules"class="section-header">Modules<ahref="#modules"class="anchor">§</a></h2><ulclass="item-table"><li><divclass="item-name"><aclass="mod"href="callsite/index.html"title="mod tracing_core::callsite">callsite</a></div><divclass="desc docblock-short">Callsites represent the source locations from which spans or events
originate.</div></li><li><divclass="item-name"><aclass="mod"href="dispatcher/index.html"title="mod tracing_core::dispatcher">dispatcher</a></div><divclass="desc docblock-short">Dispatches trace events to <ahref="trait.Subscriber.html"title="trait tracing_core::Subscriber"><code>Subscriber</code></a>s.</div></li><li><divclass="item-name"><aclass="mod"href="event/index.html"title="mod tracing_core::event">event</a></div><divclass="desc docblock-short">Events represent single points in time during the execution of a program.</div></li><li><divclass="item-name"><aclass="mod"href="field/index.html"title="mod tracing_core::field">field</a></div><divclass="desc docblock-short"><code>Span</code> and <code>Event</code> key-value data.</div></li><li><divclass="item-name"><aclass="mod"href="metadata/index.html"title="mod tracing_core::metadata">metadata</a></div><divclass="desc docblock-short">Metadata describing trace data.</div></li><li><divclass="item-name"><aclass="mod"href="span/index.html"title="mod tracing_core::span">span</a></div><divclass="desc docblock-short">Spans represent periods of time in the execution of a program.</div></li><li><divclass="item-name"><aclass="mod"href="subscriber/index.html"title="mod tracing_core::subscriber">subscriber</a></div><divclass="desc docblock-short">Collectors collect and record trace data.</div></li></ul><h2id="macros"class="section-header">Macros<ahref="#macros"class="anchor">§</a></h2><ulclass="item-table"><li><divclass="item-name"><aclass="macro"href="macro.identify_callsite.html"title="macro tracing_core::identify_callsite">identify_callsite</a></div><divclass="desc docblock-short">Statically constructs an <ahref="callsite/struct.Identifier.html"title="struct tracing_core::callsite::Identifier"><code>Identifier</code></a> for the provided <ahref="trait.Callsite.html"title="trait tracing_core::Callsite"><code>Callsite</code></a>.</div></li><li><divclass="item-name"><aclass="macro"href="macro.metadata.html"title="macro tracing_core::metadata">metadata</a></div><divclass="desc docblock-short">Statically constructs new span <ahref="struct.Metadata.html"title="struct tracing_core::Metadata">metadata</a>.</div></li></ul><h2id="structs"class="section-header">Structs<ahref="#structs"class="anchor">§</a></h2><ulclass="item-table"><li><divclass="item-name"><aclass="struct"href="struct.Dispatch.html"title="struct tracing_core::Dispatch">Dispatch</a></div><divclass="desc docblock-short"><code>Dispatch</code> trace data to a <ahref="trait.Subscriber.html"title="trait tracing_core::Subscriber"><code>Subscriber</code></a>.</div></li><li><divclass="item-name"><aclass="struct"href="struct.Event.html"title="struct tracing_core::Event">Event</a></div><divclass="desc docblock-short"><code>Event</code>s represent single points in time where something occurred during the
execution of a program.</div></li><li><divclass="item-name"><aclass="struct"href="struct.Field.html"title="struct tracing_core::Field">Field</a></div><divclass="desc docblock-short">An opaque key allowing <em>O</em>(1) access to a field in a <code>Span</code>’s key-value
data.</div></li><li><divclass="item-name"><aclass="struct"href="struct.Level.html"title="struct tracing_core::Level">Level</a></div><divclass="desc docblock-short">Describes the level of verbosity of a span or event.</div></li><li><divclass="item-name"><aclass="struct"href="struct.LevelFilter.html"title="struct tracing_core::LevelFilter">LevelFilter</a></div><divclass="desc docblock-short">A filter comparable to a verbosity <ahref="struct.Level.html"title="struct tracing_core::Level"><code>Level</code></a>.</div></li><li><divclass="item-name"><aclass="struct"href="struct.Metadata.html"title="struct tracing_core::Metadata">Metadata</a></div><divclass="desc docblock-short">Metadata describing a <ahref="span/index.html"title="mod tracing_core::span">span</a> or <ahref="event/index.html"title="mod tracing_core::event">event</a>.</div></li><li><divclass="item-name"><aclass="struct"href="struct.Once.html"title="struct tracing_core::Once">Once</a></div><divclass="desc docblock-short">A synchronization primitive which can be used to run a one-time global
initialization. Useful for one-time initialization for FFI or related
functionality. This type can only be constructed with <ahref="struct.Once.html#method.new"title="associated function tracing_core::Once::new"><code>Once::new()</code></a>.</div></li></ul><h2id="traits"class="section-header">Traits<ahref="#traits"class="anchor">§</a></h2><ulclass="item-table"><li><divclass="item-name"><aclass="trait"href="trait.Callsite.html"title="trait tracing_core::Callsite">Callsite</a></div><divclass="desc docblock-short">Trait implemented by callsites.</div></li><li><divclass="item-name"><aclass="trait"href="trait.Subscriber.html"title="trait tracing_core::Subscriber">Subscriber</a></div><divclass="desc docblock-short">Trait representing the functions required to collect trace data.</div></li></ul></section></div></main></body></html>