title: what does - if(1, true) - mean?
body: <p>I came across this code:</p>
  
  <pre><code>if (1, true) {/*...*/}
  </code></pre>
  
  <p>What does it actually mean?
  While this evaluates to true:</p>
  
  <pre><code>void foo(){}
  ...
  if(1, foo()) {/*...*/}
  </code></pre>
  
  <p>this doesnt compile:</p>
  
  <pre><code>void foo(){}
  ...
  if (1 == foo()) {/*...*/}
  </code></pre>
  
  <p>obviously because compiler expects foo() to return some integral value. I thought that the comma translates to some operator.
  Does that comma in the if clause translate to something internally?</p>