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<h1 class='fqn'><span class='in-band'>Function <a href='index.html'>serde_json</a>::<wbr><a class="fn" href=''>from_value</a></span><span class='out-of-band'><span id='render-detail'>
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<pre class='rust fn'>pub fn from_value<T>(value: <a class="enum" href="../serde_json/value/enum.Value.html" title="enum serde_json::value::Value">Value</a>) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><T, <a class="struct" href="../serde_json/error/struct.Error.html" title="struct serde_json::error::Error">Error</a>> <span class="where fmt-newline">where<br> T: <a class="trait" href="../serde/de/trait.DeserializeOwned.html" title="trait serde::de::DeserializeOwned">DeserializeOwned</a>, </span></pre><div class='docblock'><p>Interpret a <code>serde_json::Value</code> as an instance of type <code>T</code>.</p>
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<p>This conversion can fail if the structure of the Value does not match the
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structure expected by <code>T</code>, for example if <code>T</code> is a struct type but the Value
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contains something other than a JSON map. It can also fail if the structure
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is correct but <code>T</code>'s implementation of <code>Deserialize</code> decides that something
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is wrong with the data, for example required struct fields are missing from
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the JSON map or some number is too big to fit in the expected primitive
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type.</p>
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<pre class="rust rust-example-rendered">
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<span class="attribute">#[<span class="ident">macro_use</span>]</span>
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<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">serde_json</span>;
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<span class="attribute">#[<span class="ident">macro_use</span>]</span>
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<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Deserialize</span>, <span class="ident">Debug</span>)]</span>
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<span class="ident">fingerprint</span>: <span class="ident">String</span>,
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<span class="ident">location</span>: <span class="ident">String</span>,
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}
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<span class="kw">fn</span> <span class="ident">main</span>() {
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<span class="comment">// The type of `j` is `serde_json::Value`</span>
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<span class="kw">let</span> <span class="ident">j</span> <span class="op">=</span> <span class="macro">json</span><span class="macro">!</span>({
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<span class="string">"fingerprint"</span>: <span class="string">"0xF9BA143B95FF6D82"</span>,
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<span class="string">"location"</span>: <span class="string">"Menlo Park, CA"</span>
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});
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<span class="kw">let</span> <span class="ident">u</span>: <span class="ident">User</span> <span class="op">=</span> <span class="ident">serde_json</span>::<span class="ident">from_value</span>(<span class="ident">j</span>).<span class="ident">unwrap</span>();
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<span class="macro">println</span><span class="macro">!</span>(<span class="string">"{:#?}"</span>, <span class="ident">u</span>);
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