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Re: raise should not change continuation



>>>>> "Marc" == Marc Feeley <feeley@xxxxxxxxxxxxxxxx> writes:

>> The text in SRFI 18 you're referring to talks about primitives.
>> SRFI 34 doesn't say anything about how primitives raise exceptions.
>> 
>> The specifications of RAISE and WITH-EXCEPTION-HANDLER in SRFI 18
>> don't say anything about the dynamic environment or the continuation
>> of the exception handler.  The single example given doesn't constrain
>> this further, either.

Marc> But "raise" is a primitive so I don't see how a Scheme implementation
Marc> that conforms to SRFI 18 can also conform to SRFI 34 as currently
Marc> defined.

Obviously, we're running into subtle issues concerning the semantics
of English.  Maybe some other native speakers can clarify how they
read this.

But the way I read SRFI 18, RAISE doesn't "raise an exception" itself:
it calls the exception handler.  One of the problems in SRFI 18 is
that the term "exception" is poorly defined.  In the sense of SRFI 34
("exception" = "exceptional situation"), the exceptional occurred
*before* the call to RAISE---the call itself is merely an indication
that it happened.

-- 
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla