Integer Overflow

[Ursus Horibilis]

"Michael Hudson" <mwh at python.net> wrote in message
news:u8zcst6uj.fsf at python.net...
> "Ursus Horibilis" <ursus_horibilis at hotmail.com> writes:
>
> > Okay.  My next project was to do the same thing with 64-bit
> > numbers.
>
> This makes a difference how, exactly?

It doesn't make a difference; that was the point!

>
> > So how do I disable trapping for integer overflow?
>
> You can't, in the way you want anyway.
>
> You could always write a class that uses longs and chops off
all but
> the first n bits of the result.  This wouldn't do performance
any
> favours, I uspect.

It sounds like such algorithms must be written in C or some
other language and then integrated into the Python program.

>
> Not that in 2.1:
>
>     >>> 2*sys.maxint
>     Traceback (most recent call last):
>       File "<stdin>", line 1, in ?
>     OverflowError: integer multiplication
>
> but in 2.2:
>
>     >>> 2*sys.maxint
>     4294967294L
>

At the moment, I'm working with 2.0.  Is it legal to assign a
(long) to an (int) if the long contains a number that is bigger
than the (int) can store?