[Python-Dev] Making None a keyword

[Guido van Rossum]

> I think it's a small project.  We've got a new node type in the
> grammar -- None -- and we'll need a new opcode -- LOAD_NONE.  The
> compiler just needs to generate a LOAD_NONE for every None node.
> 
> Does the parser prevent assignment to None?  Or does the compiler need
> to check for the use of None in an assignment?

The compiler needs to check.  It's just like assigning to a literal:
the parser has no power to prevent this, so the compiler has to act as
a safeguard.

--Guido van Rossum (home page: http://www.python.org/~guido/)