Detailed Specification
12. Exception handling and Debugging
[Disagreement with ANS] 12.1.4 If the line number is omitted, the value of EXLINE is 0. 12.1.4 If an exit-do or exit-for statement is executed in the exception-handler of a when-use-block that is contained in a do-block or for-block, the execution exits from the exception handler. (ANS does not mention this.) 12.1.6 Even if an exception occurs within a def-statement, this system obeys the rule in 12.1.4. (The description in ANS may be incorrect.) 12.2.4 Results of trace-statement may slightly differ from the standard, in particular, even if an assign-statement is executed, and if the value of the variable is not changed, no report shall be outputted. 12.2.6 Only array elements that are changed in values shall be reported.
If a routine (or the main program) has a when-in block that has an exception-handler containing a GOSUB~RETURN subroutine, the routine can not have a GOSUB~RETURN subroutine that is not contained in any protection block.
EXTYPE,RETRY and CONTINUE do not work properly for exceptrions raised in exception handlers.