How do I check if a StringStream variable is empty/null?
<p>Just a quick question here guys. I've been searching to no avail so far.</p>

<p>Thanks!</p>

<p>A bit more info here:</p>

<pre><code>stringstream report_string;

report_string &lt;&lt; "some string here...";
</code></pre>

<p>In my code itself are various conditions for assigning values to the report_string variable.</p>

<p>I'd like to check whether it was assigned a value or not.</p>
