ample, consider the following
example of compound addition and assignment.</p>
<pre class="stan"><code>real x = 5;
x += 7;  // value of x is now 12</code></pre>
<p>The compound arithmetic and assignment statement above is equivalent
to the following long form.</p>
<pre class="stan"><code>x = x + 7;</code></pre>
<p>In general, the compound form</p>
<pre class="stan"><code>x op= y</code></pre>
<p>will be equivalent to</p>
<pre class="stan"><code>x = x op y;</code></pre>
<p>The compound statement will be legal