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<div class="titlepage"><div><div><h3 class="title">
<a name="faq.why_doesn_t_my_operator_work"></a><a class="link" href="why_doesn_t_my_operator_work.html" title="Why doesn't my *= operator work?">Why doesn't my <code class="computeroutput"><span class="special">*=</span></code> operator work?</a>
</h3></div></div></div>
<p>
        <span class="bold"><strong>Q:</strong></span> <span class="emphasis"><em>I have exported my class to
        python, with many overloaded operators. it works fine for me except the
        <code class="computeroutput"><span class="special">*=</span></code> operator. It always tells
        me "can't multiply sequence with non int type". If I use <code class="computeroutput"><span class="identifier">p1</span><span class="special">.</span><span class="identifier">__imul__</span><span class="special">(</span><span class="identifier">p2</span><span class="special">)</span></code>
        instead of <code class="computeroutput"><span class="identifier">p1</span> <span class="special">*=</span>
        <span class="identifier">p2</span></code>, it successfully executes my
        code. What's wrong with me?</em></span>
      </p>
<p>
        <span class="bold"><strong>A:</strong></span> There's nothing wrong with you. This
        is a bug in Python 2.2. You can see the same effect in Pure Python (you can
        learn a lot about what's happening in Boost.Python by playing with new-style
        classes in Pure Python).
      </p>
<pre class="programlisting"><span class="special">&gt;&gt;&gt;</span> <span class="keyword">class</span> <span class="identifier">X</span><span class="special">(</span><span class="identifier">object</span><span class="special">):</span>
<span class="special">...</span>     <span class="identifier">def</span> <span class="identifier">__imul__</span><span class="special">(</span><span class="identifier">self</span><span class="special">,</span> <span class="identifier">x</span><span class="special">):</span>
<span class="special">...</span>         <span class="identifier">print</span> <span class="char">'imul'</span>
<span class="special">...</span>
<span class="special">&gt;&gt;&gt;</span> <span class="identifier">x</span> <span class="special">=</span> <span class="identifier">X</span><span class="special">()</span>
<span class="special">&gt;&gt;&gt;</span> <span class="identifier">x</span> <span class="special">*=</span> <span class="number">1</span>
</pre>
<p>
        To cure this problem, all you need to do is upgrade your Python to version
        2.2.1 or later.
      </p>
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