[Wolfram Hinderer] > Yes, list building from a generator expression *is* expensive. And > join has to do it, because it has to iterate twice over the iterable > passed in: once for calculating the memory needed for the joined > string, and once more to actually do the join (this is implementation > dependent, of course). If the iterable is a list already, the list > building is not needed.
Good analysis. That is exactly what is going on under the hood. Raymond -- http://mail.python.org/mailman/listinfo/python-list
