[Python-3000] Equality of range objects

[Steven Bethard]

On Tue, Apr 8, 2008 at 7:25 AM, Anand Balachandran Pillai
<abpillai at gmail.com> wrote:
> Hi,
>
>     There seems to be inconsistency in the way the new range(...)
>  type implements equality and inequality operators.
>
>  In Python 2.x, range(...) of course returns lists and when you
>  equate lhs of two range(...) functions over  the same range, you
>  get True, since we are comparing equal lists.
>
>  Python 2.5.1 (r251:54863, Sep  6 2007, 17:27:08)
>  [GCC 4.1.1 20061011 (Red Hat 4.1.1-30)] on linux2
>  Type "help", "copyright", "credits" or "license" for more information.
>  >>> range(5,10)==range(5,10)
>  True
>  >>>
>
>  In Py3k, however I see the following behavior.
>  Python 3.0a4+ (py3k:62126, Apr  3 2008, 16:28:40)
>  [GCC 4.1.2 20070626 (Red Hat 4.1.2-13)] on linux2
>  Type "help", "copyright", "credits" or "license" for more information.
>  >>> range(5,10)==range(5,10)
>  False
>  >>> r1=range(5,10)
>  >>> r2=range(5,10)
>  >>> r1==r2
>  False
>  >>> r1 != r2
>  True
>
>  Won't this be quite confusing for people who carry forward their
>  code from 2.x to 3.0 ?

People carrying code from 2.x to 3.0 should be using xrange, not range::

    ActivePython 2.5.1.1 (ActiveState Software Inc.) based on
    Python 2.5.1 (r251:54863, May  1 2007, 17:47:05) [MSC v.1310 32
bit (Intel)] on win32
    Type "help", "copyright", "credits" or "license" for more information.
    >>> xrange(5, 10) == xrange(5, 10)
    False

Steve
-- 
I'm not *in*-sane. Indeed, I am so far *out* of sane that you appear a
tiny blip on the distant coast of sanity.
 --- Bucky Katt, Get Fuzzy