38 lines
981 B
Python
38 lines
981 B
Python
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from __future__ import generators
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try:
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reversed = reversed
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except NameError:
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def reversed(sequence):
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"""reversed(sequence) -> reverse iterator over values of the sequence
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Return a reverse iterator
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"""
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if hasattr(sequence, '__reversed__'):
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return sequence.__reversed__()
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if not hasattr(sequence, '__getitem__'):
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raise TypeError("argument to reversed() must be a sequence")
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return reversed_iterator(sequence)
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class reversed_iterator(object):
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def __init__(self, seq):
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self.seq = seq
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self.remaining = len(seq)
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def __iter__(self):
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return self
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def next(self):
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i = self.remaining
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if i > 0:
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i -= 1
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item = self.seq[i]
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self.remaining = i
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return item
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raise StopIteration
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def __length_hint__(self):
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return self.remaining
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