820 ;;Quote: problems with error handling by return code and status flags; checked at call sites; harder to read; multiple error cases ignored; harder to modify; expands set of legal values

820 ;;Quote: use error handling to reduce testing for rare conditions and control flow interruptions

820+;;Quote: use error handling to terminate incomplete operations

820+;;Quote: error handling should be extensible for new and modified exceptions

821 ;;Quote: a faulting execution raises an event that is propagated to an exception handler in a source execution; may differ

821+;;Quote: an exception handler catches the event and either raises an exception or handles the event

821+;;Quote: an exception handler may goto a nonlocal label, terminate intervening blocks, retry, or resume

823 ;;Quote: multiple derivation is rejected for exceptions; ambiguous handlers; should handle both exceptions

825 ;;Quote: exception lists are too restrictive for function signatures; interacts with type system; preclude reuse; rebranding hides low-level errors; asynchronous exceptions

825 ;;Quote: throwing error propagation returns to the handler using stack unwinding while resuming propagation returns to the raise, if possible

826 ;;Quote: recursive resuming may occur when resuming with exception handlers in previous scopes; only criticism of resuming propagation

830 ;;Quote: Mesa prevents recursive resuming by entering a handler only once; can lead to odd behavior

831 ;;Quote: consequential propagation prevents recursive resuming of exceptions; if a handler cannot handle an event then it should not handle its consequent events

833 ;;Quote: use implicit and explicit polling for asynchronous exceptions; use hierarchical disabling, queuing, and out of order delivery