Ok,
record/data class currently provides getters and toString/equals/hashCode, what
if i want to add a compareTo.
In Haskell, it's easy, one can use 'deriving', in Java, it can be written that
way,
record Point(int x, int y) implements Comparable<Point>
deriving equals, hashCode, toString, compareTo;
For the compiler, the method exists in the supertypes, so the signature of the
method can be computed from the super types,
after each generated method use an invokedynamic with the same meta protocol (a
list of getters),
so if by convention "equals", "hashCode", "toString", "compareTo" are the names
of some bootstrap methods in a class DerivingMetaFactory,
it can be trivial for a JDK developer to add a new bootstrap method without
having to change the JLS.
So my point is, that we can specify once how the compiler should generate codes
for any generated methods in an extensible way.
regards,
Rémi
