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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="`GroupingMap` is an intermediate struct for efficient group-and-fold operations. It groups elements by their key and at the same time fold each group using some aggregating operation."><title>GroupingMap in itertools::structs - Rust</title><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"><link rel="stylesheet" href="../../static.files/normalize-76eba96aa4d2e634.css"><link rel="stylesheet" href="../../static.files/rustdoc-ac92e1bbe349e143.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="itertools" data-themes="" data-resource-suffix="" data-rustdoc-version="1.76.0 (07dca489a 2024-02-04)" data-channel="1.76.0" data-search-js="search-2b6ce74ff89ae146.js" data-settings-js="settings-4313503d2e1961c2.js" ><script src="../../static.files/storage-f2adc0d6ca4d09fb.js"></script><script defer src="sidebar-items.js"></script><script defer src="../../static.files/main-305769736d49e732.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-feafe1bb7466e4bd.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 struct"><!--[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">&#9776;</button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../itertools/index.html">itertools</a><span class="version">0.12.1</span></h2></div><h2 class="location"><a href="#">GroupingMap</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block method"><li><a href="#method.aggregate">aggregate</a></li><li><a href="#method.collect">collect</a></li><li><a href="#method.fold">fold</a></li><li><a href="#method.fold_first">fold_first</a></li><li><a href="#method.fold_with">fold_with</a></li><li><a href="#method.max">max</a></li><li><a href="#method.max_by">max_by</a></li><li><a href="#method.max_by_key">max_by_key</a></li><li><a href="#method.min">min</a></li><li><a href="#method.min_by">min_by</a></li><li><a href="#method.min_by_key">min_by_key</a></li><li><a href="#method.minmax">minmax</a></li><li><a href="#method.minmax_by">minmax_by</a></li><li><a href="#method.minmax_by_key">minmax_by_key</a></li><li><a href="#method.product">product</a></li><li><a href="#method.sum">sum</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block trait-implementation"><li><a href="#impl-Clone-for-GroupingMap%3CI%3E">Clone</a></li><li><a href="#impl-Debug-for-GroupingMap%3CI%3E">Debug</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block synthetic-implementation"><li><a href="#impl-RefUnwindSafe-for-GroupingMap%3CI%3E">RefUnwindSafe</a></li><li><a href="#impl-Send-for-GroupingMap%3CI%3E">Send</a></li><li><a href="#impl-Sync-for-GroupingMap%3CI%3E">Sync</a></li><li><a href="#impl-Unpin-for-GroupingMap%3CI%3E">Unpin</a></li><li><a href="#impl-UnwindSafe-for-GroupingMap%3CI%3E">UnwindSafe</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block blanket-implementation"><li><a href="#impl-Any-for-T">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-T">Borrow&lt;T&gt;</a></li><li><a href="#impl-BorrowMut%3CT%3E-for-T">BorrowMut&lt;T&gt;</a></li><li><a href="#impl-From%3CT%3E-for-T">From&lt;T&gt;</a></li><li><a href="#impl-Into%3CU%3E-for-T">Into&lt;U&gt;</a></li><li><a href="#impl-ToOwned-for-T">ToOwned</a></li><li><a href="#impl-TryFrom%3CU%3E-for-T">TryFrom&lt;U&gt;</a></li><li><a href="#impl-TryInto%3CU%3E-for-T">TryInto&lt;U&gt;</a></li></ul></section><h2><a href="index.html">In itertools::structs</a></h2></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="../../itertools/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>Struct <a href="../index.html">itertools</a>::<wbr><a href="index.html">structs</a>::<wbr><a class="struct" href="#">GroupingMap</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/itertools/grouping_map.rs.html#58-60">source</a> · <button id="toggle-all-docs" title="collapse all docs">[<span>&#x2212;</span>]</button></span></div><pre class="rust item-decl"><code>pub struct GroupingMap&lt;I&gt; { <span class="comment">/* private fields */</span> }</code></pre><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p><code>GroupingMap</code> is an intermediate struct for efficient group-and-fold operations.
It groups elements by their key and at the same time fold each group
using some aggregating operation.</p>
<p>No method on this struct performs temporary allocations.</p>
</div></details><h2 id="implementations" class="section-header">Implementations<a href="#implementations" class="anchor">§</a></h2><div id="implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-GroupingMap%3CI%3E" class="impl"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#62-602">source</a><a href="#impl-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I, K, V&gt; <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/iter/traits/iterator/trait.Iterator.html" title="trait core::iter::traits::iterator::Iterator">Iterator</a>&lt;Item = <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.tuple.html">(K, V)</a>&gt;,
K: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/hash/trait.Hash.html" title="trait core::hash::Hash">Hash</a> + <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Eq.html" title="trait core::cmp::Eq">Eq</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.aggregate" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#107-121">source</a><h4 class="code-header">pub fn <a href="#method.aggregate" class="fn">aggregate</a>&lt;FO, R&gt;(self, operation: FO) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, R&gt;<div class="where">where
FO: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="enum" href="https://doc.rust-lang.org/1.76.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;R&gt;, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, V) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/option/enum.Option.html" title="enum core::option::Option">Option</a>&lt;R&gt;,</div></h4></section></summary><div class="docblock"><p>This is the generic way to perform any operation on a <code>GroupingMap</code>.
It’s suggested to use this method only to implement custom operations
when the already provided ones are not enough.</p>
<p>Groups elements from the <code>GroupingMap</code> source by key and applies <code>operation</code> to the elements
of each group sequentially, passing the previously accumulated value, a reference to the key
and the current element as arguments, and stores the results in an <code>HashMap</code>.</p>
<p>The <code>operation</code> function is invoked on each element with the following parameters:</p>
<ul>
<li>the current value of the accumulator of the group if there is currently one;</li>
<li>a reference to the key of the group this element belongs to;</li>
<li>the element from the source being aggregated;</li>
</ul>
<p>If <code>operation</code> returns <code>Some(element)</code> then the accumulator is updated with <code>element</code>,
otherwise the previous accumulation is discarded.</p>
<p>Return a <code>HashMap</code> associating the key of each group with the result of aggregation of
that group’s elements. If the aggregation of the last element of a group discards the
accumulator then there won’t be an entry associated to that group’s key.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>data = <span class="macro">vec!</span>[<span class="number">2</span>, <span class="number">8</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">9</span>, <span class="number">0</span>, <span class="number">4</span>, <span class="number">10</span>];
<span class="kw">let </span>lookup = data.into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">4</span>)
.aggregate(|acc, _key, val| {
<span class="kw">if </span>val == <span class="number">0 </span>|| val == <span class="number">10 </span>{
<span class="prelude-val">None
</span>} <span class="kw">else </span>{
<span class="prelude-val">Some</span>(acc.unwrap_or(<span class="number">0</span>) + val)
}
});
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">4</span>); <span class="comment">// 0 resets the accumulator so only 4 is summed
</span><span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">5 </span>+ <span class="number">9</span>);
<span class="macro">assert_eq!</span>(lookup.get(<span class="kw-2">&amp;</span><span class="number">2</span>), <span class="prelude-val">None</span>); <span class="comment">// 10 resets the accumulator and nothing is summed afterward
</span><span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">3</span>], <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>); <span class="comment">// The final keys are only 0, 1 and 2</span></code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.fold_with" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#156-165">source</a><h4 class="code-header">pub fn <a href="#method.fold_with" class="fn">fold_with</a>&lt;FI, FO, R&gt;(self, init: FI, operation: FO) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, R&gt;<div class="where">where
FI: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; R,
FO: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(R, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, V) -&gt; R,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and applies <code>operation</code> to the elements
of each group sequentially, passing the previously accumulated value, a reference to the key
and the current element as arguments, and stores the results in a new map.</p>
<p><code>init</code> is called to obtain the initial value of each accumulator.</p>
<p><code>operation</code> is a function that is invoked on each element with the following parameters:</p>
<ul>
<li>the current value of the accumulator of the group;</li>
<li>a reference to the key of the group this element belongs to;</li>
<li>the element from the source being accumulated.</li>
</ul>
<p>Return a <code>HashMap</code> associating the key of each group with the result of folding that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="attr">#[derive(Debug, Default)]
</span><span class="kw">struct </span>Accumulator {
acc: usize,
}
<span class="kw">let </span>lookup = (<span class="number">1</span>..=<span class="number">7</span>)
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.fold_with(|_key, _val| Default::default(), |Accumulator { acc }, _key, val| {
<span class="kw">let </span>acc = acc + val;
Accumulator { acc }
});
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>].acc, <span class="number">3 </span>+ <span class="number">6</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>].acc, <span class="number">1 </span>+ <span class="number">4 </span>+ <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>].acc, <span class="number">2 </span>+ <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.fold" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#192-198">source</a><h4 class="code-header">pub fn <a href="#method.fold" class="fn">fold</a>&lt;FO, R&gt;(self, init: R, operation: FO) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, R&gt;<div class="where">where
R: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>,
FO: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(R, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, V) -&gt; R,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and applies <code>operation</code> to the elements
of each group sequentially, passing the previously accumulated value, a reference to the key
and the current element as arguments, and stores the results in a new map.</p>
<p><code>init</code> is the value from which will be cloned the initial value of each accumulator.</p>
<p><code>operation</code> is a function that is invoked on each element with the following parameters:</p>
<ul>
<li>the current value of the accumulator of the group;</li>
<li>a reference to the key of the group this element belongs to;</li>
<li>the element from the source being accumulated.</li>
</ul>
<p>Return a <code>HashMap</code> associating the key of each group with the result of folding that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = (<span class="number">1</span>..=<span class="number">7</span>)
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.fold(<span class="number">0</span>, |acc, _key, val| acc + val);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3 </span>+ <span class="number">6</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1 </span>+ <span class="number">4 </span>+ <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">2 </span>+ <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.fold_first" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#227-237">source</a><h4 class="code-header">pub fn <a href="#method.fold_first" class="fn">fold_first</a>&lt;FO&gt;(self, operation: FO) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
FO: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(V, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, V) -&gt; V,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and applies <code>operation</code> to the elements
of each group sequentially, passing the previously accumulated value, a reference to the key
and the current element as arguments, and stores the results in a new map.</p>
<p>This is similar to <a href="struct.GroupingMap.html#method.fold" title="method itertools::structs::GroupingMap::fold"><code>fold</code></a> but the initial value of the accumulator is the first element of the group.</p>
<p><code>operation</code> is a function that is invoked on each element with the following parameters:</p>
<ul>
<li>the current value of the accumulator of the group;</li>
<li>a reference to the key of the group this element belongs to;</li>
<li>the element from the source being accumulated.</li>
</ul>
<p>Return a <code>HashMap</code> associating the key of each group with the result of folding that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = (<span class="number">1</span>..=<span class="number">7</span>)
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.fold_first(|acc, _key, val| acc + val);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3 </span>+ <span class="number">6</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1 </span>+ <span class="number">4 </span>+ <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">2 </span>+ <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.collect" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#257-271">source</a><h4 class="code-header">pub fn <a href="#method.collect" class="fn">collect</a>&lt;C&gt;(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, C&gt;<div class="where">where
C: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/default/trait.Default.html" title="trait core::default::Default">Default</a> + <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/iter/traits/collect/trait.Extend.html" title="trait core::iter::traits::collect::Extend">Extend</a>&lt;V&gt;,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and collects the elements of each group in
an instance of <code>C</code>. The iteration order is preserved when inserting elements.</p>
<p>Return a <code>HashMap</code> associating the key of each group with the collection containing that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">use </span>std::collections::HashSet;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">0</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">6</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">6</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.collect::&lt;HashSet&lt;<span class="kw">_</span>&gt;&gt;();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="macro">vec!</span>[<span class="number">0</span>, <span class="number">3</span>, <span class="number">6</span>].into_iter().collect::&lt;HashSet&lt;<span class="kw">_</span>&gt;&gt;());
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">4</span>].into_iter().collect::&lt;HashSet&lt;<span class="kw">_</span>&gt;&gt;());
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="macro">vec!</span>[<span class="number">2</span>, <span class="number">5</span>].into_iter().collect::&lt;HashSet&lt;<span class="kw">_</span>&gt;&gt;());
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.max" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#291-296">source</a><h4 class="code-header">pub fn <a href="#method.max" class="fn">max</a>(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
V: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the maximum of each group.</p>
<p>If several elements are equally maximum, the last element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.max();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">12</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">8</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.max_by" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#317-325">source</a><h4 class="code-header">pub fn <a href="#method.max_by" class="fn">max_by</a>&lt;F&gt;(self, compare: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/cmp/enum.Ordering.html" title="enum core::cmp::Ordering">Ordering</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the maximum of each group
with respect to the specified comparison function.</p>
<p>If several elements are equally maximum, the last element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.max_by(|_key, x, y| y.cmp(x));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.max_by_key" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#346-352">source</a><h4 class="code-header">pub fn <a href="#method.max_by_key" class="fn">max_by_key</a>&lt;F, CK&gt;(self, f: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; CK,
CK: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the element of each group
that gives the maximum from the specified function.</p>
<p>If several elements are equally maximum, the last element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.max_by_key(|_key, <span class="kw-2">&amp;</span>val| val % <span class="number">4</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.min" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#372-377">source</a><h4 class="code-header">pub fn <a href="#method.min" class="fn">min</a>(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
V: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the minimum of each group.</p>
<p>If several elements are equally minimum, the first element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.min();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">5</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.min_by" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#398-406">source</a><h4 class="code-header">pub fn <a href="#method.min_by" class="fn">min_by</a>&lt;F&gt;(self, compare: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/cmp/enum.Ordering.html" title="enum core::cmp::Ordering">Ordering</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the minimum of each group
with respect to the specified comparison function.</p>
<p>If several elements are equally minimum, the first element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.min_by(|_key, x, y| y.cmp(x));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">12</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">8</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.min_by_key" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#427-433">source</a><h4 class="code-header">pub fn <a href="#method.min_by_key" class="fn">min_by_key</a>&lt;F, CK&gt;(self, f: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; CK,
CK: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and finds the element of each group
that gives the minimum from the specified function.</p>
<p>If several elements are equally minimum, the first element is picked.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.min_by_key(|_key, <span class="kw-2">&amp;</span>val| val % <span class="number">4</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">12</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">4</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">8</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.minmax" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#462-467">source</a><h4 class="code-header">pub fn <a href="#method.minmax" class="fn">minmax</a>(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, <a class="enum" href="../enum.MinMaxResult.html" title="enum itertools::MinMaxResult">MinMaxResult</a>&lt;V&gt;&gt;<div class="where">where
V: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and find the maximum and minimum of
each group.</p>
<p>If several elements are equally maximum, the last element is picked.
If several elements are equally minimum, the first element is picked.</p>
<p>See <a href="../trait.Itertools.html#method.minmax" title="method itertools::Itertools::minmax">.minmax()</a> for the non-grouping version.</p>
<p>Differences from the non grouping version:</p>
<ul>
<li>It never produces a <code>MinMaxResult::NoElements</code></li>
<li>It doesn’t have any speedup</li>
</ul>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum and maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">use </span>itertools::MinMaxResult::{OneElement, MinMax};
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.minmax();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], MinMax(<span class="number">3</span>, <span class="number">12</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], MinMax(<span class="number">1</span>, <span class="number">7</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], OneElement(<span class="number">5</span>));
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.minmax_by" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#492-518">source</a><h4 class="code-header">pub fn <a href="#method.minmax_by" class="fn">minmax_by</a>&lt;F&gt;(self, compare: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, <a class="enum" href="../enum.MinMaxResult.html" title="enum itertools::MinMaxResult">MinMaxResult</a>&lt;V&gt;&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/cmp/enum.Ordering.html" title="enum core::cmp::Ordering">Ordering</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and find the maximum and minimum of
each group with respect to the specified comparison function.</p>
<p>If several elements are equally maximum, the last element is picked.
If several elements are equally minimum, the first element is picked.</p>
<p>It has the same differences from the non-grouping version as <code>minmax</code>.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum and maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">use </span>itertools::MinMaxResult::{OneElement, MinMax};
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.minmax_by(|_key, x, y| y.cmp(x));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], MinMax(<span class="number">12</span>, <span class="number">3</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], MinMax(<span class="number">7</span>, <span class="number">1</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], OneElement(<span class="number">5</span>));
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.minmax_by_key" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#543-549">source</a><h4 class="code-header">pub fn <a href="#method.minmax_by_key" class="fn">minmax_by_key</a>&lt;F, CK&gt;(self, f: F) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, <a class="enum" href="../enum.MinMaxResult.html" title="enum itertools::MinMaxResult">MinMaxResult</a>&lt;V&gt;&gt;<div class="where">where
F: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/function/trait.FnMut.html" title="trait core::ops::function::FnMut">FnMut</a>(<a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;K</a>, <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;V</a>) -&gt; CK,
CK: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/cmp/trait.Ord.html" title="trait core::cmp::Ord">Ord</a>,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and find the elements of each group
that gives the minimum and maximum from the specified function.</p>
<p>If several elements are equally maximum, the last element is picked.
If several elements are equally minimum, the first element is picked.</p>
<p>It has the same differences from the non-grouping version as <code>minmax</code>.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the minimum and maximum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">use </span>itertools::MinMaxResult::{OneElement, MinMax};
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.minmax_by_key(|_key, <span class="kw-2">&amp;</span>val| val % <span class="number">4</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], MinMax(<span class="number">12</span>, <span class="number">3</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], MinMax(<span class="number">4</span>, <span class="number">7</span>));
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], OneElement(<span class="number">5</span>));
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.sum" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#570-575">source</a><h4 class="code-header">pub fn <a href="#method.sum" class="fn">sum</a>(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
V: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/arith/trait.Add.html" title="trait core::ops::arith::Add">Add</a>&lt;V, Output = V&gt;,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and sums them.</p>
<p>This is just a shorthand for <code>self.fold_first(|acc, _, val| acc + val)</code>.
It is more limited than <code>Iterator::sum</code> since it doesn’t use the <code>Sum</code> trait.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the sum of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.sum();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3 </span>+ <span class="number">9 </span>+ <span class="number">12</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1 </span>+ <span class="number">4 </span>+ <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">5 </span>+ <span class="number">8</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details><details class="toggle method-toggle" open><summary><section id="method.product" class="method"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#596-601">source</a><h4 class="code-header">pub fn <a href="#method.product" class="fn">product</a>(self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/std/collections/hash/map/struct.HashMap.html" title="struct std::collections::hash::map::HashMap">HashMap</a>&lt;K, V&gt;<div class="where">where
V: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/ops/arith/trait.Mul.html" title="trait core::ops::arith::Mul">Mul</a>&lt;V, Output = V&gt;,</div></h4></section></summary><div class="docblock"><p>Groups elements from the <code>GroupingMap</code> source by key and multiply them.</p>
<p>This is just a shorthand for <code>self.fold_first(|acc, _, val| acc * val)</code>.
It is more limited than <code>Iterator::product</code> since it doesn’t use the <code>Product</code> trait.</p>
<p>Returns a <code>HashMap</code> associating the key of each group with the product of that group’s elements.</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>itertools::Itertools;
<span class="kw">let </span>lookup = <span class="macro">vec!</span>[<span class="number">1</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">12</span>].into_iter()
.into_grouping_map_by(|<span class="kw-2">&amp;</span>n| n % <span class="number">3</span>)
.product();
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">0</span>], <span class="number">3 </span>* <span class="number">9 </span>* <span class="number">12</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">1</span>], <span class="number">1 </span>* <span class="number">4 </span>* <span class="number">7</span>);
<span class="macro">assert_eq!</span>(lookup[<span class="kw-2">&amp;</span><span class="number">2</span>], <span class="number">5 </span>* <span class="number">8</span>);
<span class="macro">assert_eq!</span>(lookup.len(), <span class="number">3</span>);</code></pre></div>
</div></details></div></details></div><h2 id="trait-implementations" class="section-header">Trait Implementations<a href="#trait-implementations" class="anchor">§</a></h2><div id="trait-implementations-list"><details class="toggle implementors-toggle" open><summary><section id="impl-Clone-for-GroupingMap%3CI%3E" class="impl"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#56">source</a><a href="#impl-Clone-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.clone" class="method trait-impl"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#56">source</a><a href="#method.clone" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html#tymethod.clone" class="fn">clone</a>(&amp;self) -&gt; <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;</h4></section></summary><div class='docblock'>Returns a copy of the value. <a href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html#tymethod.clone">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_from" class="method trait-impl"><span class="rightside"><span class="since" title="Stable since Rust version 1.0.0">1.0.0</span> · <a class="src" href="https://doc.rust-lang.org/1.76.0/src/core/clone.rs.html#169">source</a></span><a href="#method.clone_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html#method.clone_from" class="fn">clone_from</a>(&amp;mut self, source: <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;Self</a>)</h4></section></summary><div class='docblock'>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html#method.clone_from">Read more</a></div></details></div></details><details class="toggle implementors-toggle" open><summary><section id="impl-Debug-for-GroupingMap%3CI%3E" class="impl"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#56">source</a><a href="#impl-Debug-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.fmt" class="method trait-impl"><a class="src rightside" href="../../src/itertools/grouping_map.rs.html#56">source</a><a href="#method.fmt" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/fmt/trait.Debug.html#tymethod.fmt" class="fn">fmt</a>(&amp;self, f: &amp;mut <a class="struct" href="https://doc.rust-lang.org/1.76.0/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>&lt;'_&gt;) -&gt; <a class="type" href="https://doc.rust-lang.org/1.76.0/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></h4></section></summary><div class='docblock'>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/1.76.0/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details></div><h2 id="synthetic-implementations" class="section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor">§</a></h2><div id="synthetic-implementations-list"><section id="impl-RefUnwindSafe-for-GroupingMap%3CI%3E" class="impl"><a href="#impl-RefUnwindSafe-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/panic/unwind_safe/trait.RefUnwindSafe.html" title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a>,</div></h3></section><section id="impl-Send-for-GroupingMap%3CI%3E" class="impl"><a href="#impl-Send-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Send.html" title="trait core::marker::Send">Send</a>,</div></h3></section><section id="impl-Sync-for-GroupingMap%3CI%3E" class="impl"><a href="#impl-Sync-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sync.html" title="trait core::marker::Sync">Sync</a>,</div></h3></section><section id="impl-Unpin-for-GroupingMap%3CI%3E" class="impl"><a href="#impl-Unpin-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Unpin.html" title="trait core::marker::Unpin">Unpin</a>,</div></h3></section><section id="impl-UnwindSafe-for-GroupingMap%3CI%3E" class="impl"><a href="#impl-UnwindSafe-for-GroupingMap%3CI%3E" class="anchor">§</a><h3 class="code-header">impl&lt;I&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <a class="struct" href="struct.GroupingMap.html" title="struct itertools::structs::GroupingMap">GroupingMap</a>&lt;I&gt;<div class="where">where
I: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/panic/unwind_safe/trait.UnwindSafe.html" title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a>,</div></h3></section></div><h2 id="blanket-implementations" class="section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor">§</a></h2><div id="blanket-implementations-list"><details class="toggle implementors-toggle"><summary><section id="impl-Any-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/any.rs.html#140">source</a><a href="#impl-Any-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/any/trait.Any.html" title="trait core::any::Any">Any</a> for T<div class="where">where
T: 'static + ?<a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/any.rs.html#141">source</a><a href="#method.type_id" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/any/trait.Any.html#tymethod.type_id" class="fn">type_id</a>(&amp;self) -&gt; <a class="struct" href="https://doc.rust-lang.org/1.76.0/core/any/struct.TypeId.html" title="struct core::any::TypeId">TypeId</a></h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a href="https://doc.rust-lang.org/1.76.0/core/any/trait.Any.html#tymethod.type_id">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/borrow.rs.html#208">source</a><a href="#impl-Borrow%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.Borrow.html" title="trait core::borrow::Borrow">Borrow</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/borrow.rs.html#210">source</a><a href="#method.borrow" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.Borrow.html#tymethod.borrow" class="fn">borrow</a>(&amp;self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;T</a></h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/borrow.rs.html#216">source</a><a href="#impl-BorrowMut%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.BorrowMut.html" title="trait core::borrow::BorrowMut">BorrowMut</a>&lt;T&gt; for T<div class="where">where
T: ?<a class="trait" href="https://doc.rust-lang.org/1.76.0/core/marker/trait.Sized.html" title="trait core::marker::Sized">Sized</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/borrow.rs.html#217">source</a><a href="#method.borrow_mut" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut" class="fn">borrow_mut</a>(&amp;mut self) -&gt; <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;mut T</a></h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a href="https://doc.rust-lang.org/1.76.0/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#763">source</a><a href="#impl-From%3CT%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for T</h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#766">source</a><a href="#method.from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.From.html#tymethod.from" class="fn">from</a>(t: T) -&gt; T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#747-749">source</a><a href="#impl-Into%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle method-toggle" open><summary><section id="method.into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#756">source</a><a href="#method.into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.Into.html#tymethod.into" class="fn">into</a>(self) -&gt; U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p>
<p>That is, this conversion is whatever the implementation of
<code><a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.From.html" title="trait core::convert::From">From</a>&lt;T&gt; for U</code> chooses to do.</p>
</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-ToOwned-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/alloc/borrow.rs.html#83-85">source</a><a href="#impl-ToOwned-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html" title="trait alloc::borrow::ToOwned">ToOwned</a> for T<div class="where">where
T: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Owned" class="associatedtype trait-impl"><a href="#associatedtype.Owned" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html#associatedtype.Owned" class="associatedtype">Owned</a> = T</h4></section></summary><div class='docblock'>The resulting type after obtaining ownership.</div></details><details class="toggle method-toggle" open><summary><section id="method.to_owned" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/alloc/borrow.rs.html#88">source</a><a href="#method.to_owned" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned" class="fn">to_owned</a>(&amp;self) -&gt; T</h4></section></summary><div class='docblock'>Creates owned data from borrowed data, usually by cloning. <a href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><details class="toggle method-toggle" open><summary><section id="method.clone_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/alloc/borrow.rs.html#92">source</a><a href="#method.clone_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html#method.clone_into" class="fn">clone_into</a>(&amp;self, target: <a class="primitive" href="https://doc.rust-lang.org/1.76.0/std/primitive.reference.html">&amp;mut T</a>)</h4></section></summary><div class='docblock'>Uses borrowed data to replace owned data, usually by cloning. <a href="https://doc.rust-lang.org/1.76.0/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#803-805">source</a><a href="#impl-TryFrom%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.Into.html" title="trait core::convert::Into">Into</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl"><a href="#associatedtype.Error" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html#associatedtype.Error" class="associatedtype">Error</a> = <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/convert/enum.Infallible.html" title="enum core::convert::Infallible">Infallible</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#810">source</a><a href="#method.try_from" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html#tymethod.try_from" class="fn">try_from</a>(value: U) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;T, &lt;T as <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;U&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-T" class="impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#788-790">source</a><a href="#impl-TryInto%3CU%3E-for-T" class="anchor">§</a><h3 class="code-header">impl&lt;T, U&gt; <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryInto.html" title="trait core::convert::TryInto">TryInto</a>&lt;U&gt; for T<div class="where">where
U: <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;,</div></h3></section></summary><div class="impl-items"><details class="toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl"><a href="#associatedtype.Error-1" class="anchor">§</a><h4 class="code-header">type <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryInto.html#associatedtype.Error" class="associatedtype">Error</a> = &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl"><a class="src rightside" href="https://doc.rust-lang.org/1.76.0/src/core/convert/mod.rs.html#795">source</a><a href="#method.try_into" class="anchor">§</a><h4 class="code-header">fn <a href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryInto.html#tymethod.try_into" class="fn">try_into</a>(self) -&gt; <a class="enum" href="https://doc.rust-lang.org/1.76.0/core/result/enum.Result.html" title="enum core::result::Result">Result</a>&lt;U, &lt;U as <a class="trait" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html" title="trait core::convert::TryFrom">TryFrom</a>&lt;T&gt;&gt;::<a class="associatedtype" href="https://doc.rust-lang.org/1.76.0/core/convert/trait.TryFrom.html#associatedtype.Error" title="type core::convert::TryFrom::Error">Error</a>&gt;</h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main></body></html>
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