when an iterable object is exhausted or not

[Franck Ditter]

Two similar iterable objects but with a different behavior :

$$$ i = range(2,5)
$$$ for x in i : print(x,end=' ')

2 3 4 
$$$ for x in i : print(x,end=' ')        # i is not exhausted   

2 3 4 

--------- Compare with :

$$$ i = filter(lambda c : c.isdigit(), 'a1b2c3')
$$$ for x in i : print(x,end=' ')

1 2 3 
$$$ for x in i : print(x,end=' ')        # i is exhausted

$$$ 

IMHO, this should not happen in Py3k.
What is the rationale of this (bad ?) design, which forces the programmer
to memorize which one is exhaustable and which one is not ?...

      franck