[Python-Dev] Making None a keyword

Guido van Rossum guido@python.org
Fri, 26 Apr 2002 14:34:32 -0400

>     Ellipsis
>     False
>     None
>     NotImplemented
>     True
> are the builtin singleton data constants, so I'm +1 on those.

I'll go along with True and False, since I expect that these will be
frequently used (though still not as frequently as None).

Ellipsis is very rarely used (only by numeric code implementing
multi-dimensional arrays), NotImplemented is used somewhat more but
still pretty esoteric.  So I'm -1 on those.

Otherwise, you might as well start making all built-in functions
keywords -- that would probably buy you more, too.  E.g. if range were
a keyword, the compiler could implement "for i in range(n)" without
materializing the whole list at once.  But I'm not proposing that; I
think there's a better way to get the same effect without making
everything a keyword.

I just think that None is important enough to become a keyword.

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