Smart slicing

[Neal Becker]

bearophile wrote:

> Trevor Parscal Wrote:
>> Allowing out-of-bounds indexes hides bugs. An out of bounds index should
>> always be an error which is considered exceptional.
> 
> I (like all all Ruby and Python programmers) use such things all the time,
> and only once in a while it actually produces a bug in my programs, so I
> presume you are wrong.
> 
> 
>> If you handle the index wrapping yourself, it's obvious to everyone that
>> in that particular case that would be an OK thing to do - in all other
>> cases, it could potentially be an error..
> 
> In my post I am talking about using an alternative (standard) syntax fur
> such usages (to keep speed up, not to remove bugs).
> 

I use my own vector/matix code in python.  I made sure that out-of-bounds
indexes are not silently ignored.  This is a very valuable feature.

y[a:b:c] = z[d:e]

I rely on the error checking here to tell me when I mis-calculated.  It has
found many errors for me.