OptionalBooleanBinaryFunction
class OptionalBooleanBinaryFunction<A, OA : ObservableValue<A>, B, OB : ObservableValue<B>>(argA: OA, argB: OB, lambda: (A, B) -> Boolean?) : BinaryFunction<Boolean?, A, OA, B, OB> , ObservableOptionalBoolean
Boilerplate which avoids having to use generics.
Similar to BooleanBinaryFunction, but the value can also be null.