I assumed that that setting was intended to enable the experimental synthetic-code-based macro debugging. But even without this, we need to know if the breakpoint is within a macro argument, as it might end up emitted in an inner class of the logically enclosing class. As such, we need to use a wildcard in the breakpoint specification. The treatment is similar to by-name arguments.

Perhaps there is a cleaner way to implement this, I did get a little bit lost in this class. But the end result should be that the user can set breakpoints at all the `println`'s in the example in the commit message, using default IDE settings.