> After considering several alternatives and trying out a few ideas with a > modified list object Bengt Richter posted, (Thank You), I think I've > found a way to make slice operation (especially far end indexing) > symmetrical and more consistent.
I don't know that it makes it more consistent. I could be persuaded, but it would have to be by real-life examples with calculated slice indices and stride. I do this thing all the time, and find the current rules simple and very consistent. Occasionally, I might wish that things were a little different, but there is always a workaround. I would have to see some real code examples, of sufficient scope to see that there are fewer workarounds with this proposal than with the current implementation. FWIW, there is a reasonable workaround for the case where the indices might be negative and you would like zero or greater to mean 'end of list'. If "x" is the index variable, you can use the expression (x<0 and x or None) for the index value in the slice. If you find yourself doing this often, you can write a little function for it -- def EndIndex(x): return x<0 and x or None. But in real code, I fear you might need a similar helper function for similar issues with your change. I just don't know what those are without more thought. Regards, Pat -- http://mail.python.org/mailman/listinfo/python-list
