e being declared.</p>
<p>Any type may be assigned. For example,</p>
<pre class="stan"><code>matrix[3, 2] a = b;</code></pre>
<p>declares a matrix variable <code>a</code> and assigns it to the value of <code>b</code>,
which must be of type <code>matrix</code> for the compound statement to be well
formed. The sizes of matrices are not part of their static typing and
cannot be validated until run time.</p>
</div>
<div id="right-hand-side-expressions" class="section level3 unnumbered">
<h3>Right-Hand Side Expre