Support for JML `TYPE` about key

[mattulbrich]

I think this is easily achievable in KeY. All we need is a sort SORT in KeY and a sort-depending symbol alpha::sort, a few taclets that connect them to the subtype relation of the Java program and JavaDL. The JML translation is probably easily adapted. A topic for the HacKeYthon?

[wadoon]

Does this hurt the theory on the meta-level?

• What is \type(\type(a))?
• Is \type only defined for reference datatypes?
• Is \type(2) well-defined? Or is \type(2)` a reference type due to autoboxing?
• Is \TYPE <: \TYPE?
• Is x <: y similar to instanceOf? Then, will it support annotations?

[flo2702]

\type(\TYPE) <: \type(\TYPE) holds.

\type is defined for type names. I.e., \type(ClassName), \type(int), and \type(\TYPE) are all legal expressions, but \type(\type(...)) and \type(2) are not.

The subtype operator supports only base types without annotations.

[flo2702]

Closed by #3465