A Hodgepodge of Python

Re:A Hodgepodge of Python by Sharlin on Thursday September 15, 2011 @05:40PM (#3002235)

  >>> reversed([])
  <listreverseiterator object at 0xb73ff7cc>

reversed() does not create a new list, it just returns a reverse-order view of the same list. Of course, often this is exactly what is needed.

[ Parent | on HN ]

Re:A Hodgepodge of Python by akx on Friday September 16, 2011 @06:17AM (#3003886)

And more often than not `xrange` is what one needs, not `range`. (Not relevant with Py3k though, but everyone is still in 2.x-verse.)

[ Parent | on HN ]

Re:A Hodgepodge of Python by lysium on Friday September 16, 2011 @08:09AM (#3004115)

    >>> xrange(13)[::-1]
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    TypeError: sequence index must be integer, not 'slice'

[ Parent | on HN ]

Re:A Hodgepodge of Python by akx on Friday September 16, 2011 @09:15AM (#3004295)

  >>> list(range(13)[::-1]) == list(xrange(12, -1, -1))
  True

[ Parent | on HN ]

Re:A Hodgepodge of Python by lysium on Friday September 16, 2011 @08:08AM (#3004112)

True: $ python -mtimeit -s'l=range(1000)' 'a=[i for i in reversed(l)]' 10000 loops, best of 3: 37.7 usec per loop

[ Parent | on HN ]