On 2/3/2014 5:22 PM, andrea crotti wrote:
That's already better, another thing which I just thought about could
be this (which actually happened a few times):
def original_gen():
count = 0
while count < 10:
yield count
count += 1
def consumer():
gen = original_gen()
# lis = list(gen)
for n in gen:
print(n * 2)
if I uncomment the line with "lis = list(gen)"
it won't print anything anymore, because we have to make sure we only
loop over ONCE.
That maybe is a better example of possible drawback? (well maybe not a
drawback but a potential common mistake)
A couple of days ago I made a similar error. Stdlib code
a = list(f(iterable1))
return g(a) # g just need an iterable
The return value is buggy. Insert for i in a: print(i) to debug. Notice
that g does not need a concrete list. Delete list wrapper. Return value
goes away. Because I did other things between the last two steps, I did
not immediately make the connection and was initially puzzled. Deleting
debug code made things work again. Using itertools.tee would have done
the same.
--
Terry Jan Reedy
--
https://mail.python.org/mailman/listinfo/python-list
