Hi,
One of the next things I will look into with invokedynamic is surely the
casting too boolean using invokedynamic.But I have the feeling something
is off here.
If we have an expression
if (foo) m()
then m() will be called if foo can be converted to boolean true, also
known as Groovy Truth(ness). From a runtime perspective the rules are
easy, just expand it to foo.asBoolean(). But that is not how we compile
this. Instead if we know the type of foo and it satisfies certain
conditions we shortcut.
* foo static type is boolean => do nothing
* foo static type is other primitive => convert directly in bytecode.
* foo runtime value is null => false
* other cases call asBoolean()
This means we can replace the asBoolean method on everything except null
and primitives. We do this mostly for efficiency reasons. Of and there
is the specialty that asType(Boolean) falls back to asBoolean basically.
Which makes sense, though a cleaner solution would probably have been to
always use asType... of course more complicated performance wise as
well.. possibly.
My question is though if we want to keep this mixed cases. Alternatives
would be:
* always use asBoolean
* exempt asBoolean from replacement in meta classes
bye Jochen
