On Aug 31, 10:21 am, zaur <szp...@gmail.com> wrote: > On 29 авг, 16:45, zaur <szp...@gmail.com> wrote: > > > > > > > Python 2.6.2 (r262:71600, Apr 16 2009, 09:17:39) > > [GCC 4.0.1 (Apple Computer, Inc. build 5250)] on darwin > > Type "copyright", "credits" or "license()" for more information.>>> a=1 > > >>> x=[a] > > >>> id(a)==id(x[0]) > > True > > >>> a+=1 > > >>> a > > 2 > > >>> x[0] > > > 1 > > > I thought that += should only change the value of the int object. But > > += create new. > > Is this intentional? > > As a result of this debate is not whether we should conclude that > there should be two types of integers in python: 1) immutable numbers, > which behave as constant value; 2) mutable numbers, which behave as > variable value?
You are free to use third-party modules (such as numpy) which provide mutable numbers. I see no reason to include any mutable number type standard library, as not many people will require the performance benefits and/or indirection of mutable numbers, and those who do are free to use third- party modules that provide them. Carl Banks -- http://mail.python.org/mailman/listinfo/python-list
