for a different reason. If the
first argument is promoted to a real value, it matches the first
signature, whereas if the second argument is promoted to a real value,
it matches the second signature. The problem is that these both
require one promotion, so the function name <code>bar</code> is ambiguous.
If there is not a unique function requiring fewer promotions than all
others, as with <code>bar(1, 1)</code> given the two declarations above,
the Stan compiler will flag the expression as illegal.</p>
</di