If it's possible, i would like to discuss about IdentityClass again.

As noted in the last draft, adding IdentityClass automatically at runtime is 
not a compatible change if tests that uses Class::getInterfaces() are not 
written correctly,
and sadly, a lot of tests are written that way. I'm guilty to having written 
those tests too.
I don't believe that the solution is to tweak the reflection because adding 
IdentityClass at runtime is already a hack and introducing a hack² (hack square 
hack) is usually where we should stop before anyone sanity goes under the bus.

The purpose of IdentityClass is
- to have a classfile for the javadoc describing the behavior of all identity 
class
- to be used as type or bound of type parameter.

Apart the result of Class::getInterfaces() being hardcoded, IdentityClass has 
to other issues, as javadoc container, given that IdentityClass is inserted by 
the VM, it means there is no place in the Java code where someone can click to 
see the javadoc in an IDE, we have the same issue with java.lang.Record 
currently, the class is added by javac automatically and unlike java.lang.Enum, 
there is no method useful on java.lang.Record (equals/hashCode and toString are 
defined directly on the record) so very few of my student where able to 
understand why a record with a NaN value was equals to itself.
But there is a more serious issue, using IdentityClass is not backward 
compatible with Object.
When we have introduced IdentityClass, one scenario was to be able to declare 
that the type parameter corresponding to the keys (K) to only support identity 
class.
This is not possible using IdentityClass because the erasure of K will be 
IdentityClass instead of Object (IdentityClass also appears when the compiler 
will to a lub, so the common class of String and URI will be computed as 
IdentityClass instead of Object leading to source compatibility issues).

I think at that point, we should go back to our blackboard and see if there is 
no other solution.

I see two, one is to do *nothing* and do not add a type saying that only 
identity class is a corner case after all,
the other is to piggyback on erasure not unlike Scala does, i.e. IdentityClass 
is a fake class that is erased to Object at runtime.

regards,
Rémi

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