Question about None

Andre Engels andreengels at
Sun Jun 14 11:49:42 EDT 2009

On Sat, Jun 13, 2009 at 7:23 PM, John Yeung<gallium.arsenide at> wrote:

> Paul LaFollette is probably thinking along the lines of formal logic
> or set theory.  It's a little bit confused because programming isn't
> quite the same as math, and so it's a common question when designing
> and implementing programming languages how far to take certain
> abstractions.  In some languages, nil, null, or none will try to
> behave as mathematically close to "nothing" (complete absence of
> anything) as possible, even though in reality they have to have some
> concrete implementation, such as perhaps being a singleton object.
> But mathematically speaking, it's intuitive that "nothing" would match
> any type.

I don't see why that would be the case. Something of the type "thingy"
is ONE thingy. Nothing is ZERO thingies, so it is not something of the
type "thingy". A car is a single car. Nothing is zero cars, which is
not a car, just like two cars is not a car.

André Engels, andreengels at

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