On Jul 16, 2:21 am, Michael Torrie <[EMAIL PROTECTED]> wrote: > iu2 wrote: > > I still don't understand: In each recursive call to flatten, acc > > should be bound to a new [], shouldn't it? Why does the binding happen > > only on the first call to flatten? > > Nope. In each new call it's (re)bound to the same original list, which > you've added to as your function continues--it's mutable. Default > variables that are bound to mutable objects are one of the big caveats > that is mentioned in the FAQ.
Thanks guys, it's clear now -- http://mail.python.org/mailman/listinfo/python-list