[Python-3000] Exceptions internals and removing sys.exc_*

[Ron Adam]

Tony Lownds wrote:

> http://mail.python.org/pipermail/python-dev/2007-January/070665.html
> 
> What's the cost of keeping sys.exc_info() on 3.0? If that cost is a  
> hindrance on 3.0, then
> fine, sys.exc_info() and the ability for module authors to use a  
> single codebase on 2.x and
> 3.0 can be given up.

Well, This is how I see it. (but I believe it's been said here before a well)

It's not a present cost, but a future cost.  There have been lots of times where 
a suggestion has been put forth in 2.x to do x,y and z.  Only to be found, no 
that can't be done because it would break, u, v or w.  The more things there 
are, the more chance something new will break one of them.

There are a lot of things that haven't been done yet in computer science, and to 
give python 3.x the best chance of being a part of those future things, (by 
adding them to python), it's best that it is as clean as it can be at the start. 
  Of course 'clean as can be' is subjective, so it's not a line carved in stone. 
  And it's also not one blindly carved.

I expect that no matter how different 2.x is from 3.x, someone will find a way 
to make 2.x programs work on it with a minimum of trouble if not outright as is. 
    Writing an 2.x interpreter for 3.x is probably very doable, (especially with 
a  little 'C' magic thrown in).  And it may not even run slower.  One of the 
benefits of having a clean break, is it gives a sure target for such efforts.

Yes, I'm a optimist. ;-)
   Ron