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                                <h1 id="custom-serialization"><a name="custom-serialization" class="plugin-anchor" href="#custom-serialization"><i class="fa fa-link" aria-hidden="true"></i></a>Custom serialization</h1>
<p>Serde&apos;s <a href="derive.html">derive macro</a> through <code>#[derive(Serialize, Deserialize)]</code> provides
reasonable default serialization behavior for structs and enums and it can be
customized to some extent using <a href="attributes.html">attributes</a>. For unusual needs, Serde allows
full customization of the serialization behavior by manually implementing
<a href="https://docs.rs/serde/1/serde/ser/trait.Serialize.html" target="_blank"><code>Serialize</code></a> and <a href="https://docs.rs/serde/1/serde/de/trait.Deserialize.html" target="_blank"><code>Deserialize</code></a> traits for your type.</p>
<p>The traits each have a single method:</p>
<pre><code class="lang-rust"><span class="hljs-keyword">pub</span> <span class="hljs-class"><span class="hljs-keyword">trait</span> <span class="hljs-title">Serialize</span></span> {
    <span class="hljs-function"><span class="hljs-keyword">fn</span> <span class="hljs-title">serialize</span></span>&lt;S&gt;(&amp;<span class="hljs-keyword">self</span>, serializer: S) -&gt; <span class="hljs-built_in">Result</span>&lt;S::<span class="hljs-literal">Ok</span>, S::Error&gt;
    <span class="hljs-keyword">where</span>
        S: Serializer;
}

<span class="hljs-keyword">pub</span> <span class="hljs-class"><span class="hljs-keyword">trait</span> <span class="hljs-title">Deserialize</span></span>&lt;<span class="hljs-symbol">&apos;de</span>&gt;: <span class="hljs-built_in">Sized</span> {
    <span class="hljs-function"><span class="hljs-keyword">fn</span> <span class="hljs-title">deserialize</span></span>&lt;D&gt;(deserializer: D) -&gt; <span class="hljs-built_in">Result</span>&lt;<span class="hljs-keyword">Self</span>, D::Error&gt;
    <span class="hljs-keyword">where</span>
        D: Deserializer&lt;<span class="hljs-symbol">&apos;de</span>&gt;;
}
</code></pre>
<p>These methods are generic over the serialization format, represented by the
<a href="https://docs.rs/serde/1/serde/ser/trait.Serializer.html" target="_blank"><code>Serializer</code></a> and <a href="https://docs.rs/serde/1/serde/de/trait.Deserializer.html" target="_blank"><code>Deserializer</code></a> traits. For example there is one Serializer
type for JSON and a different one for Postcard.</p>
<ul>
<li><a href="impl-serialize.html">Implementing <code>Serialize</code></a></li>
<li><a href="impl-deserialize.html">Implementing <code>Deserialize</code></a></li>
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