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Date: Wed, 04 Jul 2012 19:39:21 -0500
From: Evan Driscoll <driscoll@cs.wisc.edu>
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To: Paul Rubin <phr-2012@nightsong.com>
Subject: Re: 2 + 2 = 5
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On 7/4/2012 14:37, Paul Rubin wrote:
> I just came across this (https://gist.github.com/1208215):
>=20
>     import sys
>     import ctypes
>     pyint_p =3D ctypes.POINTER(ctypes.c_byte*sys.getsizeof(5))
>     five =3D ctypes.cast(id(5), pyint_p)
>     print(2 + 2 =3D=3D 5) # False
>     five.contents[five.contents[:].index(5)] =3D 4
>     print(2 + 2 =3D=3D 5) # True (must be sufficiently large values of =
2 there...)
>=20
> Heh.  The author is apparently anonymous, I guess for good reason.

Probably just nostalgic for old Fortran, which, supposedly, allowed you
to change the values of literals by passing them to a function by
reference and then modifying the value.

Evan



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