 let mut x = 5;

// x = 6; // no problem!
x = 6; // 問題なし!
}</span><pre class='rust rust-example-rendered'>
<span class='kw'>let</span> <span class='kw-2'>mut</span> <span class='ident'>x</span> <span class='op'>=</span> <span class='number'>5</span>;

<span class='ident'>x</span> <span class='op'>=</span> <span class='number'>6</span>; <span class='comment'>// 問題なし!</span></pre>

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