all() returning a generator?

Question

So I want to test if a list is sorted. After reading this page, I did this:

ll = [ 0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15 ]
all(b >= a for a, b in zip(ll, ll[1:]) )

Output

<generator object <genexpr> at 0x10d9ecaa0>

Ok so all() return a generator. But this is what the Python documentation says about all():

Return True if all elements of the iterable are true (or if the iterable is empty)

What am i missing?

Can't reproduce either. Please give a [SSCCE](http://sscce.org/). — , Feb 14 '14 at 15:24
Perhaps your `all` got overwritten by a user-made function. If you do `print all`, does it say ``? — Kevin, Feb 14 '14 at 15:26
.. and this is why no one should ever do `from numpy import *`, or use any environment which does the same. — DSM, Feb 14 '14 at 15:27
@DSM I am using IPython notebook... Thanks for helping me find the culprit! — usual me, Feb 14 '14 at 15:29

Veedrac · Accepted Answer · 2014-07-27T01:52:50.100

11

This is a problem of those silly star-imports:

from numpy import *

ll = [ 0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15 ]
all(b >= a for a, b in zip(ll, ll[1:]) )
#>>> <generator object <genexpr> at 0x7f976073fdc0>

Python's all works fine.

You can access it via __builtin__ module in python2 and builtins module in python3:

import __builtin__
__builtin__.all(b >= a for a, b in zip(ll, ll[1:]))

edited Jul 27 '14 at 01:52

answered Feb 14 '14 at 15:27

Veedrac

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all() returning a generator?

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