None assigment

[Neil Schemenauer]

On Thu, Feb 08, 2001 at 01:15:23PM -0500, D-Man wrote:
> Interesting.  So normally "None" is a special keyword (that is a
> reference to an object) ,  but that doesn't prevent one from creating
> a local variable named "None" that shadows the keyword.

Sounds like something another P language would do.  Things are
simpler.  None is a builtin.  It exists in the __builtin__
module.  The buildin module is searched for names after the
global namespace is searched.

    >>> print None # find the binding for None, it is in __builtin__
    None
    >>> None = "spam" # make a global binding for None
    >>> print None
    spam
    >>> import __builtin__
    >>> print __builtin__.None # __builtin__ binding is still there
    None
    >>> del None # remove global binding
    >>> print None
    None
    >>> __builtin__.None = "spam" # change __builtin__ binding (evil)
    >>> print None
    spam
 
Cheers,

  Neil