On Sun, Nov 8, 2009 at 6:21 AM, Deniz Dogan
What point are you trying to make by distinguishing JSON from JavaScript? JSON is a subset of JavaScript, they share the same type system. "Null can be only one value." This doesn't make sense to me, since as you say null is not a type, but a value.
-- Deniz Dogan
It seems I underestimated the typedness of null in JavaScript :) I checked the ECMAScript specification, and it does refer to a "null type".. so titto was right.[1] My opinion is that JSON's 'type system' should be analyzed orthogonal to JavaScript's regardless. If JSON is a subset of JavaScript, it is primarily a syntactic one. When I said "Null can be only one value", implying that null is a type, I was referring to JSON's null, not JavaScript's null. In JSON, null *is* definitely a unit type. When considering mappings between Haskell and JSON in the case of (), we should see that () is a unit type in Haskell, null is a unit type in JSON (regardless of its role in JavaScript), and maybe try to associate them. —Matt [1] I was misled by the fact that typeof null = 'object'. The logic behind this, I think, is that null is meant to be bound to a variable that would otherwise be a reference to an actual object value. Many have criticized this result, e.g. Douglas Crockford ( http://javascript.crockford.com/remedial.html)