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Field attributes
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<h1>
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<a href="." >Field attributes</a>
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<h1 id="field-attributes"><a name="field-attributes" class="plugin-anchor" href="#field-attributes"><i class="fa fa-link" aria-hidden="true"></i></a>Field attributes</h1>
<ul>
<li><h5 id="rename"><a name="rename" class="plugin-anchor" href="#rename"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(rename = "name")]</code> </h5>
<p>Serialize and deserialize this field with the given name instead of its Rust
name. This is useful for <a href="attr-rename.html">serializing fields as camelCase</a> or
serializing fields with names that are reserved Rust keywords.</p>
<p>Allows specifying independent names for serialization vs deserialization:</p>
<ul>
<li><code>#[serde(rename(serialize = "ser_name"))]</code></li>
<li><code>#[serde(rename(deserialize = "de_name"))]</code></li>
<li><code>#[serde(rename(serialize = "ser_name", deserialize = "de_name"))]</code></li>
</ul>
</li>
<li><h5 id="alias"><a name="alias" class="plugin-anchor" href="#alias"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(alias = "name")]</code> </h5>
<p>Deserialize this field from the given name <em>or</em> from its Rust name. May be
repeated to specify multiple possible names for the same field.</p>
</li>
<li><h5 id="default"><a name="default" class="plugin-anchor" href="#default"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(default)]</code> </h5>
<p>If the value is not present when deserializing, use the <code>Default::default()</code>.</p>
</li>
<li><h5 id="default--path"><a name="default--path" class="plugin-anchor" href="#default--path"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(default = "path")]</code> </h5>
<p>If the value is not present when deserializing, call a function to get a
default value. The given function must be callable as <code>fn() -> T</code>. For example
<code>default = "empty_value"</code> would invoke <code>empty_value()</code> and <code>default =
"SomeTrait::some_default"</code> would invoke <code>SomeTrait::some_default()</code>.</p>
</li>
<li><h5 id="flatten"><a name="flatten" class="plugin-anchor" href="#flatten"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(flatten)]</code> </h5>
<p>Flatten the contents of this field into the container it is defined in.</p>
<p>This removes one level of structure between the serialized representation and
the Rust data structure representation. It can be used for factoring common
keys into a shared structure, or for capturing remaining fields into a map
with arbitrary string keys. The <a href="attr-flatten.html">struct flattening</a> page
provides some examples.</p>
<p><em>Note:</em> this attribute is not supported in combination with structs that use
<a href="container-attrs.html#deny_unknown_fields"><code>deny_unknown_fields</code></a>. Neither the outer nor inner flattened struct should
use that attribute.</p>
</li>
</ul>
<ul>
<li><h5 id="skip"><a name="skip" class="plugin-anchor" href="#skip"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(skip)]</code> </h5>
<p>Skip this field: do not serialize or deserialize it.</p>
<p>When deserializing, Serde will use <code>Default::default()</code> or the function
given by <code>default = "..."</code> to get a default value for this field.</p>
</li>
<li><h5 id="skip_serializing"><a name="skip_serializing" class="plugin-anchor" href="#skip_serializing"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(skip_serializing)]</code> </h5>
<p>Skip this field when serializing, but not when deserializing.</p>
</li>
<li><h5 id="skip_deserializing"><a name="skip_deserializing" class="plugin-anchor" href="#skip_deserializing"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(skip_deserializing)]</code> </h5>
<p>Skip this field when deserializing, but not when serializing.</p>
<p>When deserializing, Serde will use <code>Default::default()</code> or the function
given by <code>default = "..."</code> to get a default value for this field.</p>
</li>
<li><h5 id="skip_serializing_if"><a name="skip_serializing_if" class="plugin-anchor" href="#skip_serializing_if"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(skip_serializing_if = "path")]</code> </h5>
<p>Call a function to determine whether to skip serializing this field. The given
function must be callable as <code>fn(&T) -> bool</code>, although it may be generic over
<code>T</code>. For example <code>skip_serializing_if = "Option::is_none"</code> would skip an
Option that is None.</p>
</li>
<li><h5 id="serialize_with"><a name="serialize_with" class="plugin-anchor" href="#serialize_with"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(serialize_with = "path")]</code> </h5>
<p>Serialize this field using a function that is different from its
implementation of <code>Serialize</code>. The given function must be callable as
<code>fn<S>(&T, S) -> Result<S::Ok, S::Error> where S: Serializer</code>, although it
may also be generic over <code>T</code>. Fields used with <code>serialize_with</code> are not
required to implement <code>Serialize</code>.</p>
</li>
<li><h5 id="deserialize_with"><a name="deserialize_with" class="plugin-anchor" href="#deserialize_with"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(deserialize_with = "path")]</code> </h5>
<p>Deserialize this field using a function that is different from its
implementation of <code>Deserialize</code>. The given function must be callable as
<code>fn<'de, D>(D) -> Result<T, D::Error> where D: Deserializer<'de></code>, although it
may also be generic over <code>T</code>. Fields used with <code>deserialize_with</code> are not
required to implement <code>Deserialize</code>.</p>
</li>
<li><h5 id="with"><a name="with" class="plugin-anchor" href="#with"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(with = "module")]</code> </h5>
<p>Combination of <code>serialize_with</code> and <code>deserialize_with</code>. Serde will use
<code>$module::serialize</code> as the <code>serialize_with</code> function and
<code>$module::deserialize</code> as the <code>deserialize_with</code> function.</p>
</li>
<li><h5 id="borrow"><a name="borrow" class="plugin-anchor" href="#borrow"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(borrow)]</code> and <code>#[serde(borrow = "'a + 'b + ...")]</code> </h5>
<p>Borrow data for this field from the deserializer by using zero-copy
deserialization. See <a href="lifetimes.html#borrowing-data-in-a-derived-impl">this example</a>.</p>
</li>
<li><h5 id="bound"><a name="bound" class="plugin-anchor" href="#bound"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(bound = "T: MyTrait")]</code> </h5>
<p>Where-clause for the <code>Serialize</code> and <code>Deserialize</code> impls. This replaces any
trait bounds inferred by Serde for the current field.</p>
<p>Allows specifying independent bounds for serialization vs deserialization:</p>
<ul>
<li><code>#[serde(bound(serialize = "T: MySerTrait"))]</code></li>
<li><code>#[serde(bound(deserialize = "T: MyDeTrait"))]</code></li>
<li><code>#[serde(bound(serialize = "T: MySerTrait", deserialize = "T: MyDeTrait"))]</code></li>
</ul>
</li>
<li><h5 id="getter"><a name="getter" class="plugin-anchor" href="#getter"><i class="fa fa-link" aria-hidden="true"></i></a><code>#[serde(getter = "...")]</code> </h5>
<p>This is used when deriving <code>Serialize</code> for a <a href="remote-derive.html">remote type</a>
that has one or more private fields.</p>
</li>
</ul>
</section>
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