def __init__(self):
Steven D'Aprano
steve+comp.lang.python at pearwood.info
Wed Apr 27 00:54:27 EDT 2016
On Wednesday 27 April 2016 02:59, Chris Kaynor wrote:
> On Tue, Apr 26, 2016 at 9:32 AM, Steven D'Aprano <steve at pearwood.info>
> wrote:
>
>> Actually immutable, short of doing wicked things with ctypes.
>>
>
> By wicked things with ctypes, do you mean something like this? By no means
> do I suggest this actually be used by anybody for any reason.
>
> Tested with '2.7.10 (default, Jul 14 2015, 19:46:27) \n[GCC 4.2.1
> Compatible Apple LLVM 6.0 (clang-600.0.39)]'
>
> import ctypes
> def changeTuple(tuple, index, newValue):
> obj = ctypes.cast(id(tuple), ctypes.POINTER(ctypes.c_long))
> obj[3+index] = id(newValue)
>
>>>> a = ('a','b','c')
>>>> changeTuple(a, 0, 1)
>>>> a
> (1, 'b', 'c')
>>>> changeTuple(a, 1, 3)
>>>> a
> (1, 3, 'c')
You're a bad, bad man :-)
--
Steve
More information about the Python-list
mailing list