I met the following surprising behaviour >>> def gen0(): ... for i in range(3): ... def gen1(): ... yield i ... yield i, gen1() ... >>> for i,g in gen0(): print i, g.next() ... 0 0 1 1 2 2 >>> for i,g in list(gen0()): print i, g.next() ... 0 2 1 2 2 2
If this is not a bug, it is at least quite confusing. The apparent reason is that the free variables in nested generator definitions are not bound (to a value) at invocation time but only at access time. Almost surely, the same applies to all locally defined functions with free variables. This would mean that locally defined functions with free variables are very risky in generators. -- Dieter -- http://mail.python.org/mailman/listinfo/python-list
