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<a href="." >Feature flags</a>
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<h1 id="feature-flags"><a name="feature-flags" class="plugin-anchor" href="#feature-flags"><i class="fa fa-link" aria-hidden="true"></i></a>Feature flags</h1>
<p>The <code>serde</code> crate defines some <a href="https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section" target="_blank">Cargo features</a> to enable using Serde in a
variety of freestanding environments.</p>
<p>Building Serde with <code>default-features = false</code>, you will receive a stock
<code>no_std</code> Serde with no support for any of the collection types.</p>
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<h4 id="derive"><a name="derive" class="plugin-anchor" href="#derive"><i class="fa fa-link" aria-hidden="true"></i></a><span style="font-weight:normal">features = [</span>"derive"<span style="font-weight:normal">]</span> </h4>
<p>Provide derive macros for the Serialize and Deserialize traits.</p>
<p>This is behind a feature because the derive macro implementation takes some
extra time to compile.</p>
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<p><em>This feature is enabled by default.</em></p>
<p>Provide impls for common standard library types like Vec<T> and
HashMap<K, V>. Requires a dependency on the Rust standard library.</p>
<p>See <a href="no-std.html">no-std support</a> for details.</p>
<h4 id="unstable"><a name="unstable" class="plugin-anchor" href="#unstable"><i class="fa fa-link" aria-hidden="true"></i></a><span style="font-weight:normal">features = [</span>"unstable"<span style="font-weight:normal">]</span> </h4>
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discussion of unstable functionality please refer to <a href="https://github.com/serde-rs/serde/issues/812" target="_blank">serde-rs/serde#812</a>.</p>
<h4 id="alloc"><a name="alloc" class="plugin-anchor" href="#alloc"><i class="fa fa-link" aria-hidden="true"></i></a><span style="font-weight:normal">features = [</span>"alloc"<span style="font-weight:normal">]</span> </h4>
<p>Provide impls for types in the Rust core allocation and collections library
including String, Box<T>, Vec<T>, and Cow<T>. This is a subset
of std but may be enabled without depending on all of std.</p>
<p>Requires a dependency on the <a href="https://doc.rust-lang.org/alloc/" target="_blank">core allocation library</a>.</p>
<p>See <a href="no-std.html">no-std support</a> for details.</p>
<h4 id="rc"><a name="rc" class="plugin-anchor" href="#rc"><i class="fa fa-link" aria-hidden="true"></i></a><span style="font-weight:normal">features = [</span>"rc"<span style="font-weight:normal">]</span> </h4>
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these types does not preserve identity and may result in multiple copies of the
same data. Be sure that this is what you want before enabling this feature.</p>
<p>Serializing a data structure containing reference-counted pointers will
serialize a copy of the inner value of the pointer each time a pointer is
referenced within the data structure. Serialization will not attempt to
deduplicate these repeated data.</p>
<p>Deserializing a data structure containing reference-counted pointers will not
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