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<h1><a class="header" href="#concatenating-strings-with-format" id="concatenating-strings-with-format">Concatenating strings with <code>format!</code></a></h1>
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<h2><a class="header" href="#description" id="description">Description</a></h2>
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<p>It is possible to build up strings using the <code>push</code> and <code>push_str</code> methods on a
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mutable <code>String</code>, or using its <code>+</code> operator. However, it is often more
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convenient to use <code>format!</code>, especially where there is a mix of literal and
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non-literal strings.</p>
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<h2><a class="header" href="#example" id="example">Example</a></h2>
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<pre><pre class="playground"><code class="language-rust edition2018">
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<span class="boring">#![allow(unused)]
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</span><span class="boring">fn main() {
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</span>fn say_hello(name: &str) -> String {
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// We could construct the result string manually.
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// let mut result = "Hello ".to_owned();
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// result.push_str(name);
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// result.push('!');
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// result
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// But using format! is better.
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format!("Hello {}!", name)
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}
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<span class="boring">}
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</span></code></pre></pre>
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<h2><a class="header" href="#advantages" id="advantages">Advantages</a></h2>
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<p>Using <code>format!</code> is usually the most succinct and readable way to combine strings.</p>
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<h2><a class="header" href="#disadvantages" id="disadvantages">Disadvantages</a></h2>
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<p>It is usually not the most efficient way to combine strings - a series of <code>push</code>
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operations on a mutable string is usually the most efficient (especially if the
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string has been pre-allocated to the expected size).</p>
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