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Re: No overflow in variables?

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On Wed, Jan 22, 2014 at 11:09 AM, Philip Red
<filippo.biolcati@googlemail.com> wrote:
> Hi everyone. First of all sorry if my english is not good.
> I have a question about something in Python I can not explain:
> in every programming language I know (e.g. C#) if you exceed the max-value of a certain type (e.g. a long-integer) you get an overflow. Here is a simple example in C#:
>
>         static void Main(string[] args)
>         {
>             Int64 x = Int64.MaxValue;
>             Console.WriteLine(x);       // output: 9223372036854775807
>             x = x * 2;
>             Console.WriteLine(x);       // output: -2 (overflow)
>             Console.ReadKey();
>         }
>
> Now I do the same with Python:
>
>             x = 9223372036854775807
>             print(type(x))             #   <class 'int'>
>             x = x * 2                  #   18446744073709551614
>             print(x)                   #   <class 'int'>
>             print(type(x))
>
> and I get the right output without overflow and the type is always a 'int'.
> How does Python manages internally the types and their values? Where are they stored?
>
> Thank you for your help :)

This may help you understand:

http://www.python.org/dev/peps/pep-0237/

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Thread

No overflow in variables? Philip Red <filippo.biolcati@googlemail.com> - 2014-01-22 10:09 -0800
  Re: No overflow in variables? Larry Martell <larry.martell@gmail.com> - 2014-01-22 11:18 -0700
  Re:No overflow in variables? Dave Angel <davea@davea.name> - 2014-01-22 13:26 -0500
  Re: No overflow in variables? Philip Red <filippo.biolcati@googlemail.com> - 2014-01-22 10:32 -0800
  Re: No overflow in variables? Chris Angelico <rosuav@gmail.com> - 2014-01-23 05:26 +1100
    Re: No overflow in variables? Roy Smith <roy@panix.com> - 2014-01-22 15:55 -0500
    Re: No overflow in variables? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-01-23 11:22 +1300
  Re: No overflow in variables? Philip Red <filippo.biolcati@googlemail.com> - 2014-01-22 10:48 -0800
  Re: No overflow in variables? random832@fastmail.us - 2014-01-22 18:13 -0500
  Re: No overflow in variables? Christian Heimes <christian@python.org> - 2014-01-23 10:14 +0100
  Re: No overflow in variables? Chris Angelico <rosuav@gmail.com> - 2014-01-23 20:36 +1100

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