>>> result.append('start')

Default reason:

.. skip: next if(2 > 1)

Should not run:

>>> result.append('bad 1')
>>> result.append('good 1')

.. skip: start if(2 > 1, reason='foo')

>>> result.append('bad 2')
>>> result.append('bad 3')

.. skip: end

>>> result.append('good 2')


Here's a really extreme example of computing the reason from stuff in the namespace:

.. skip:  next   if    (True, 'good reason' if result[-1] == 'good 2' else 'bad reason'  )

>>> result.append('bad 4')