Documentation for method
push-until-lazy assembled from the following types:
method push-until-lazy(Iterator: --> Mu)
Should produce values until it considers itself to be lazy, and push them onto
The Iterator role implements this method as a no-op if
is-lazy returns a True value, or as a synonym of
push-all if not.
This matters mostly for iterators that have other iterators embedded, some of which might be lazy, while others aren't.