How should types, members, and sets be represented?

[Justin Meyer]

People need to be able to define their own types that work with the set system. There are:

• Types: Something like Color,
• Members/instances: Something like "green",
• Sets: Something like ["green", "red"]

For example, a Todo might have a status property of type Color:

DefineMap.extend({
  status: Color
})

How should types, sets, and members relate to each other?

Option A

• isMember check on the Type and sets of the type.
• new Type.Set() to create a subset.

Color = Enum(["red","green", "blue"]);

Color.isMember("red") //-> true

var redAndGreen = new Color.Set(["green","red"]);

redAndGreen.isMember("red") //-> true 

var universal = Color.UNIVERSAL;

set.difference( universal, redAndGreen) //-> new Color.Set(["blue"]);

Questions:

• Should Color just be the universal set?
• Should isMember default to instanceOf? I think this should be a can-reflect thing.