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| </p><p>From GCC 3.4 calling <code class="code">s.reserve(res)</code> on a |
| <code class="code">string s</code> with <code class="code">res < s.capacity()</code> will |
| reduce the string's capacity to <code class="code">std::max(s.size(), res)</code>. |
| </p><p>This behaviour is suggested, but not required by the standard. Prior |
| to GCC 3.4 the following alternative can be used instead |
| </p><pre class="programlisting"> |
| std::string(str.data(), str.size()).swap(str); |
| </pre><p>This is similar to the idiom for reducing a <code class="code">vector</code>'s |
| memory usage (see <a class="ulink" href="../faq/index.html#5_9" target="_top">FAQ 5.9</a>) but |
| the regular copy constructor cannot be used because libstdc++'s |
| <code class="code">string</code> is Copy-On-Write. |
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