title: Why a deconstruction cannot mix declarations and expressions on the left
body: <p>I have this code:</p>
  
  <pre><code>public static (int a, int b) f12()
  {
      return (1, 2);
  }
  
  public static void test()
  {
      int a;
      (a, int b) = f12(); //here is the error
  }
  </code></pre>
  
  <p>When I try to compile it I get an error:</p>
  
  <blockquote>
    <p>A deconstruction cannot mix declarations and expressions on the left </p>
  </blockquote>
  
  <p>I don't understand why. Any suggestions?</p>