Joseph, nice table. I was just discussing it w/Markus and here's our answers to your questions: - A singleton cannot contain an instance (only classes can contain instances).
Is the following on the page incorrect then? An entity singleton context MAY have the following types of subcontexts: class, entity instance, singleton, definition, variable.
An attribute singleton context MAY have the following types of subcontexts: class, attribute instance, singleton, value, definition, variable.
Also, can you confirm whether or not instances can contain instances?
- Since variables can be typed, a typed variable can contain anything that the type of context that the variable represents can contain. For example, a variable representing a root context can contain anything a root context can contain. However, variables can also be untyped. An untyped variable can contain anything that would be valid for its position in the XDI graph model. For example, an untyped variable representing a context below the root level cannot represent a root. And an untyped variable whose parent is not a class cannot represent an instance.
- You are correct that a value context cannot contain any subcontexts. It's truly a leaf context node that can contain zero-or-one XDI literal node.
Maybe I should drop variable and value from the matrix and treat them separately.
I didn't mean beyond those seven - I meant that class, singleton, definition can all include each other freely.
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