ur code is capable of functioning whether after the assignment,
          <code class="computeroutput"><span class="identifier">a</span></code> aliases the same object
          as <code class="computeroutput"><span class="identifier">b</span></code> or not.
        </p>
<p>
          That is, you would have to discriminate in order to be consistent.
        </p>
<p>
          If in your code rebinding to another object is not an option, then it is
          very likely that binding for the first time isn't