title: What is the <=> ("spaceship", three-way comparison) operator in C++?
body: <p>While I was trying to learn about <strong>C++</strong> operators, I stumbled upon a strange comparison operator on <a href="http://en.cppreference.com/w/cpp/language/operator_comparison" rel="noreferrer">cppreference.com</a>,<sup>*</sup> in a table that looked like this:</p>
  <p><img src="https://i.stack.imgur.com/bqEv0.jpg" alt="enter image description here" /></p>
  <p>&quot;Well, if these are common operators in C++, I better learn them&quot;, I thought. But all my attempts to elucidate this mystery were unsuccessful. Even here, on Stack Overflow I had no luck in my search.</p>
  <h2>Is there a connection between <strong>&lt;=&gt;</strong> and <strong>C++</strong>?</h2>
  <p>And if there is, what does this operator do exactly?</p>
  <p><sub>* In the meantime cppreference.com updated that page and now contains information about the<code>&lt;=&gt;</code>operator.</sub></p>