'Execute this :class:`.FunctionElement` against an embedded
\'bind\' and return a scalar value.
This first calls :meth:`~.FunctionElement.select` to
produce a SELECT construct.
Note that :class:`.FunctionElement` can be passed to
the :meth:`.Connectable.scalar` method of :class:`.Connection`
or :class:`.Engine`.'

def scalar(self):

    return self.select().execute().scalar()
