## §B.2 Additions between versions

#### (1) Between OTJLD 1.0 and OTJLD 1.1

- §1.2.4.(c): Role class literal

  Made existing feature explicit and introduce new qualified class literal for externalized roles.

- §3.1.(j) and §3.5.(h) : Inferred callout

  New feature.

- §4.6.(a) : Callin-binding private methods from super classes

  Added a necessary restriction.

- §4.9 : Callin inheritance

  Clarified issues that where under-specified or insufficiently explained, specifically:

  - Effect of callin bindings on inherited or overridden base methods (§4.9.1).
  - Interplay of callin bindings and base methods with covariant return types (§4.9.3)
- §4.10: Generic replace bindings

  Reconcile type safety of replace bindings as introduced in §4.5.(d) with desirable flexibility by using type parameters.

- §7.2.(b) : Arrays of Confined

  Added a necessary restriction.

#### (2) Between OTJLD 1.1 and OTJLD 1.2

- §1.2.2.(h) : Externalized creation

  Added alternative syntax using value parameter and changed title.

- §1.2.5.(f) : Imports in role files

  Added a missing rule defining the effect of imports in role files.

- §1.3.1.(c) : @Override annotation for roles

  The regular `@Override` annotation (Java ≥5) has been extended to apply to role classes, too.

- §1.3.1.(k) : Covariant return types

  Necessary constraint for covariant return types in the presence of both implicit and explicit inheritance.

- §2.1.2.(c) : Binding to final base class

  It has been added that binding to a final base class is now considered as decapsulation, too.

- §2.2.(f) : Ambiguous lowering

  A diagnostic has been added to detect situations where lowering might be intended but fails because the declared type is `java.lang.Object`, which makes a potential lowering translation unnecessary and thus ambiguous.

- §2.3.2.(e) : Generic declared lifting

  Support passing unrelated base types into the same method with declared lifting.

- §2.6.(g) : Decapsulation via base reference

  Extended applicability of decapsulation to two more positions.

- §4.3.(f) : Base super call

  Support base calls directly to the super version of the bound base method, thus bypassing both the exact bound base method and also any further callins relating to this base method or its super version.

- §5.4.(b) : Side-effects in guard predicates

  Migrate previous note about a future feature to a regular paragraph.

- §5.4.(c) : Exceptions in guard predicates

  Clarify the effect of exceptions thrown from a guard predicate.

- §6.2.(d) : LiftingVetoException

  Added documentation for the mostly internal `LiftingVetoException` and how it could actually be used in client code.

- §6.2.(e) : Role migration

  Added two interfaces to add migration capabilities to a role class.

#### (3) Between OTJLD 1.2 and OTJLD 1.3

- §2.1.1 : Binding roles to base interfaces

  The implementation limitation mentioned in §2.1.1 has been mostly removed.

- §2.3.1.(d) : Fine-tuning role instantiation

  An annotation has been defined for modifying the semantics of lifting in order to improve performance. Also a new section has been added as §6.3 to summarize the annotation types defined in this document.

- §2.3.5 : Consequences of lifting problems

  After §2.3.4 has clarified that `LiftingFailedException` (§6.2.(d)) is indeed a checked exception, a subsection has been added defining the consequences of this exception in various program situations.

- §3.1.(k) : Callout to generic method

  Added a rule on how a callout binding may refer to a generic base method.

- §4.1.(b) : Callin binding in "unliftable" role

  Callin bindings can now be defined even in "unliftable" roles.

- §4.1.(h) : Binding to team methods

  `before` and `after` callin bindings can now bind to methods of an enclosing class, too.

- §4.8.(d) : Order when merging precedence declarations

  Clarified how several precedence declarations are merged, which was underspecified, because the C3 algorithm needs ordered inputs, but this order was not specified.

- §4.10.(e) : Propagating type parameters in callin bindings

  In addition to capturing covariant return types, a callin binding may also declared type parameters in order to propagate genericity from its base method to the role method.

- §5.3.(d) : Configuring implicit activation

  Mechanisms have been added for configuring implicit team activation. The default has been changed to not apply implicit activation. A corresponding note has also been added to §5.3

- §9.2.1.(a) : Instance constrained type parameter

  Type anchors can now be applied to type parameters, too, thus expressing a new kind of constraint on the type parameter.

#### (4) After OTJLD 1.3

- §4.1.(i): Callin to constructor

  A callin after binding can now be applied to a constructor of the base class, too.