* Terje Norderhaug [2010-03-22 20:14+0100] writes:
This has usability implications as swank clients cannot adapt to whether a frame certainly is restartable, might possibly be restartable, or definitely isn't restartable.
There's no definive answer to this question without unwinding the stack and executing unwind-protected handlers.
There is at least a definite answer to the question when the back-end does not implement a restart-frame function. When the frame definitely cannot be restarted, the swank client should obviously not present the user with the option to restart the frame.
Are you saying a back-end never can determine without actual execution that a frame on the stack for practical purposes is restartable?
Yes.
Helmut