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<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Helper macro when implementing the `Deserializer` part of a new data format for Serde."><title>forward_to_deserialize_any in serde - Rust</title><script> if (window.location.protocol !== "file:") document.write(`<link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/SourceSerif4-Regular-46f98efaafac5295.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/FiraSans-Regular-018c141bf0843ffd.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/FiraSans-Medium-8f9a781e4970d388.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../static.files/SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2">`)</script><link rel="stylesheet" href="../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../static.files/rustdoc-e935ef01ae1c1829.css"><meta name="rustdoc-vars" data-root-path="../" data-static-root-path="../static.files/" data-current-crate="serde" data-themes="" data-resource-suffix="" data-rustdoc-version="1.78.0 (9b00956e5 2024-04-29)" data-channel="1.78.0" data-search-js="search-42d8da7a6b9792c2.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../static.files/storage-4c98445ec4002617.js"></script><script defer src="sidebar-items.js"></script><script defer src="../static.files/main-12cf3b4f4f9dc36d.js"></script><noscript><link rel="stylesheet" href="../static.files/noscript-04d5337699b92874.css"></noscript><link rel="alternate icon" type="image/png" href="../static.files/favicon-16x16-8b506e7a72182f1c.png"><link rel="alternate icon" type="image/png" href="../static.files/favicon-32x32-422f7d1d52889060.png"><link rel="icon" type="image/svg+xml" href="../static.files/favicon-2c020d218678b618.svg"></head><body class="rustdoc macro"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../serde/index.html">serde</a><span class="version">1.0.200</span></h2></div><div class="sidebar-elems"></div></nav><div class="sidebar-resizer"></div>
<main><div class="width-limiter"><nav class="sub"><form class="search-form"><span></span><div id="sidebar-button" tabindex="-1"><a href="../serde/all.html" title="show sidebar"></a></div><input class="search-input" name="search" aria-label="Run search in the documentation" autocomplete="off" spellcheck="false" placeholder="Click or press S to search, ? for more options…" type="search"><div id="help-button" tabindex="-1"><a href="../help.html" title="help">?</a></div><div id="settings-menu" tabindex="-1"><a href="../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><section id="main-content" class="content"><div class="main-heading"><h1>Macro <a href="index.html">serde</a>::<wbr><a class="macro" href="#">forward_to_deserialize_any</a><button id="copy-path" title="Copy item path to clipboard"><img src="../static.files/clipboard-7571035ce49a181d.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="src" href="../src/serde/macros.rs.html#111-119">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><span class="macro">macro_rules!</span> forward_to_deserialize_any {
(&lt;<span class="macro-nonterminal">$visitor</span>:ident: Visitor&lt;<span class="macro-nonterminal">$lifetime</span>:tt&gt;&gt; $(<span class="macro-nonterminal">$func</span>:ident)<span class="kw-2">*</span>) =&gt; { ... };
($(<span class="macro-nonterminal">$func</span>:ident)<span class="kw-2">*</span>) =&gt; { ... };
}</pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Helper macro when implementing the <code>Deserializer</code> part of a new data format
for Serde.</p>
<p>Some <a href="trait.Deserializer.html"><code>Deserializer</code></a> implementations for self-describing formats do not
care what hint the <a href="de/trait.Visitor.html"><code>Visitor</code></a> gives them, they just want to blindly call
the <a href="de/trait.Visitor.html"><code>Visitor</code></a> method corresponding to the data they can tell is in the
input. This requires repetitive implementations of all the <a href="trait.Deserializer.html"><code>Deserializer</code></a>
trait methods.</p>
<div class="example-wrap edition"><a href="#" class="tooltip" title="This example runs with edition 2021"></a><pre class="rust rust-example-rendered"><code><span class="attr">#[inline]
</span><span class="kw">fn </span>deserialize_bool&lt;V&gt;(<span class="self">self</span>, visitor: V) -&gt; <span class="prelude-ty">Result</span>&lt;V::Value, <span class="self">Self</span>::Error&gt;
<span class="kw">where
</span>V: Visitor&lt;<span class="lifetime">'de</span>&gt;,
{
<span class="self">self</span>.deserialize_any(visitor)
}</code></pre></div>
<p>The <code>forward_to_deserialize_any!</code> macro implements these simple forwarding
methods so that they forward directly to <a href="trait.Deserializer.html#tymethod.deserialize_any"><code>Deserializer::deserialize_any</code></a>.
You can choose which methods to forward.</p>
<div class="example-wrap edition"><a href="#" class="tooltip" title="This example runs with edition 2021"></a><pre class="rust rust-example-rendered"><code><span class="kw">impl</span>&lt;<span class="lifetime">'de</span>&gt; Deserializer&lt;<span class="lifetime">'de</span>&gt; <span class="kw">for </span>MyDeserializer {
<span class="kw">fn </span>deserialize_any&lt;V&gt;(<span class="self">self</span>, visitor: V) -&gt; <span class="prelude-ty">Result</span>&lt;V::Value, <span class="self">Self</span>::Error&gt;
<span class="kw">where
</span>V: Visitor&lt;<span class="lifetime">'de</span>&gt;,
{
<span class="comment">/* ... */
</span>}
<span class="macro">forward_to_deserialize_any!</span> {
bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
bytes byte_buf option unit unit_struct newtype_struct seq tuple
tuple_struct map <span class="kw">struct enum </span>identifier ignored_any
}
}</code></pre></div>
<p>The macro assumes the convention that your <code>Deserializer</code> lifetime parameter
is called <code>'de</code> and that the <code>Visitor</code> type parameters on each method are
called <code>V</code>. A different type parameter and a different lifetime can be
specified explicitly if necessary.</p>
<div class="example-wrap edition"><a href="#" class="tooltip" title="This example runs with edition 2021"></a><pre class="rust rust-example-rendered"><code><span class="macro">forward_to_deserialize_any!</span> {
&lt;W: Visitor&lt;<span class="lifetime">'q</span>&gt;&gt;
bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
bytes byte_buf option unit unit_struct newtype_struct seq tuple
tuple_struct map <span class="kw">struct enum </span>identifier ignored_any
}</code></pre></div>
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