There should be multiple ways to express an absence of a value

[as-com]

For example, JavaScript has both null and undefined to express an absence of a value. PyHP++# should have multiple ways of expressing a lack of value, each with its own special behavior.

[Kampfkarren]

If we're just going based on our source languages, our options are null, NULL, and 0.

EDIT: Oh, and nullptr.

[as-com]

And None from Python

[Kampfkarren]

Should they all be aliases for each other? If not, should they equal each other?

[ghost]

They should all mean slightly different things and be used in slightly different contexts.

[mzhang28]

There should be an order of precedence for these values, in case people decide to compare them to each other. For example, if the order was something like:

• undefined
• None
• no
• any valid data type

then comparing, for example, undefined == None would return undefined, and comparing 5 == no would return no.

[ghost]

@iptq Love this idea. I may implement it into the specs if I get the time, or you can write your own if you like.