get the underlying type directly (i.e. the <em>explicitly-typed-initializer idiom</em>):</p>

<pre title="C++" style="color: #000000; font-family: monospace,monospace; font-size: 0.9em; white-space: pre-wrap; word-wrap: break-word; border: 1px solid #cccccc; border-radius: 3px; overflow: auto; padding: 6px 10px; margin-bottom: 10px;background-color:#ffffff;"><code style="color: black; font-family: monospace,monospace; font-size: 0.9em;"><span style="color: #AA0D92">auto</span> <span style="color: #000000">f