ow error
</code></pre>
<blockquote>
<p>Note:
Overflow checking is not performed in <code>-Ounchecked</code> builds.</p>
</blockquote>
</div><div class="intro-declaration"><code class="language-swift">func -=(lhs:rhs:)(lhs: inout UInt16, rhs: UInt16)</code></div><div class="discussion comment"><p>Subtracts the second value from the first and stores the difference in the
left-hand-side variable.
</p>
<p>The difference of the two arguments must be representable in the
arguments' type. In the following example,