[MATRIX-SIG] Seg fault with slice

[Janko Hauser]

In the attempt to make the nslice object more like a slice I tried a
similar approach like Konrad Hinsen in his indexing.py but get a
seg. fault if len returns sys.maxint. This happens only on Linux not on
an alpha box. There the error is:

[0 1 2]
Traceback (innermost last):
  File "nslice.py", line 46, in ?
    main()
  File "nslice.py", line 23, in main
    print a[n_sl]
ValueError: __len__() should return >= 0

Wich I also don't understand, because maxint is clearly greater than
zero.
But this happens on Linux with python1.4 and 1.5a.

Any ideas? seg faults are real show stopper in python.

__Janko

#!/usr/local/bin/python
import Numeric
import sys

N=Numeric
maxint = sys.maxint

def test():
    a = N.arange(12)
    sl = slice(0,3,None)
    n_sl = nslice(sl)

    print a[sl]
    print a[n_sl]

    return

class nslice:
    def __init__(self, index, shape=None):
        self.index = index
        self.maxint = maxint
        return

    def __getslice__(self):
        start = self.index.start
        stop = self.index.stop
        step = None
        return self[start:stop:step]

    def __len__(self):
    	return self.maxint  # No seg fault if I return 0



if __name__ == "__main__":

    test()


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