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Python 2.5 releasedPython 2.5 releasedPosted Sep 19, 2006 21:51 UTC (Tue) by dofwno (guest, #40609)Parent article: Python 2.5 released
When can we expect to get arrays with arbitrary lower indices?
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Python 2.5 released Posted Sep 20, 2006 12:06 UTC (Wed) by skaya (guest, #31233) [Link] If by "arbitrary lower indices" you mean "negative indices", methinks this will not happen, since myarray[-1] means "the last element of myarray". But you can use a hashtable for that ;-)
If you mean "an array which starts at position 10000" (for instance), I think you can achieve that with a simple wrapper around getitem/setitem.
... If you mean something else, I would be grateful if you could clarify ?
Python 2.5 released Posted Sep 20, 2006 14:25 UTC (Wed) by tjc (subscriber, #137) [Link] Just curious: why do you want arrays with arbitrary lower indices?
Python 2.5 released Posted Sep 21, 2006 20:01 UTC (Thu) by kbob (guest, #1770) [Link] It's already available in Python 2.2.
#!/usr/bin/python
class ArbitraryLowerBoundList(list):
def __init__(self, lower_bound=0, *args, **kwargs):
super(ArbitraryLowerBoundList, self).__init__(*args, **kwargs)
self.__offset = lower_bound
def lower_bound(self):
return self.__offset
def upper_bound(self):
return self.__offset + len(self)
def __setitem__(self, index, item):
s = super(ArbitraryLowerBoundList, self)
return s.__setitem__(index - self.__offset, item)
def __getitem__(self, index):
s = super(ArbitraryLowerBoundList, self)
return s.__getitem__(index - self.__offset)
if __name__ == '__main__':
a = ArbitraryLowerBoundList(10, ['a', 'b', 'c'])
assert a.lower_bound() == 10
assert a.upper_bound() == 13
assert a[10] == 'a'
a[11] = 'B'
assert a[11] == 'B'
assert a == ['a', 'B', 'c']
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