erators like <code>real * real</code> are
defined as <code>operator*(real, real)</code> in the documentation and index.</p>
<p>In matching a function definition, all of the promotion rules are in
play (integers may be promoted to reals, reals to complex, and
containers may be promoted if their types are promoted). For example,
arguments of type <code>int</code> may be promoted to type <code>real</code> or <code>complex</code> if
necessary (see the subsection on type promotion in <a href="type-inference.html