de>real</code>, it is
able to match <code>foo(real,real)</code>, and hence the type of the
function expression <code>foo(1,1.0)</code> is <code>real</code>.</p>
<p>In some cases (though not for any built-in Stan functions), a
situation may arise in which the function referred to by an
expression remains ambiguous. For example, consider a situation in
which there are exactly two functions named <code>bar</code> with the
following signatures.</p>
<pre><code>real bar(real,int);
real bar(int,real);</code></pre>