Well, it works in that the MYN parameter is a NEWed variable that keeps state. I agree the MYN* makes it into a real Factorial function rather than just a function that calls itself recursively and always returns 1.
If you do NOT want the implicit NEW MYN that occurs by the standard, you can pass a variable by using .VARNAME in the call. (of course, this doesn't work if you are passing an expression) It's not tail-end recursion optimization, because the subroutine stack still increases with each call, but it will use the same variable, so you have some optimization possible. David > > OH NEVER MIND...I'm being stupid. > > I meant to type > > Q MYN*$$FACT(MYN-1) > > but didn't. > > Anyway, I didn't expect this to work, but apparently it does. > > --- Greg Woodhouse <[EMAIL PROTECTED]> wrote: > > > Even worse > > > > > > >ZL ZZGBAD ZP > > FACT(MYN) ; ; 3/8/05 12:23pm > > Q:MYN'>0 1 > > Q $$FACT(MYN-1) > > ; > > FACT2(MYN) ; > > N X > > S X=MYN > > Q:X'>0 1 > > Q $$FACT(X-1) > > > > >W $$FACT^ZZGBAD(5) > > 1 > > >W $$FACT2^ZZGBAD(5) > > 1 > > > > > --- Greg Woodhouse <[EMAIL PROTECTED]> wrote: > > > > > Sure. > > > > > > > > > >ZL ZZGBAD ZP > > > FACT(MYN) ; ; 3/8/05 12:14pm > > > Q:MYN'>0 1 > > > S VAL=$$FACT(MYN-1) > > > S MYN=0 ;MYN changed! > > > Q VAL > > > > > > >W $$FACT^ZZGBAD(5) > > > 1 > > > > > > > > > > > > > --- Greg Kreis <[EMAIL PROTECTED]> wrote: > > > > > > > I am not following your reasoning Greg. Can you provide an > > > example? > > > > > > > > Greg Woodhouse wrote: > > > > > > > > >Another thing to watch out for is recursive calls. With the > > > scoping > > > > >works in MUMPS it seems to me that the only safe option is to > > copy > > > > >parameter values into NEW variables (so that you have a separate > > > > copy > > > > >in each stack frame). Otherwise, things might not work as you > > > > expect. > > > > > > > > > >--- Greg Woodhouse <[EMAIL PROTECTED]> wrote: > > > > > > > > > > > > > > > > > > > >>In fact, I recall creating a special lookup routine that called > > > > ^DIC > > > > >>-- > > > > >>except that I neglected to include the "I" flag for ignore > > > special > > > > >>lookup routine. Needless to say, the result was "interesting". > > > > >> > > > > >>--- Greg Kreis <[EMAIL PROTECTED]> wrote: > > > > >> > > > > >> > > > > >> > > > > >>>It can happen with repeatedly performing a DO command to any > > > > >>>location. > > > > >>>Anything that is putting new entries on the stack frame > > without > > > > >>>eventually removing them. The stack on DSM or Cache can > > > probably > > > > >>>handle > > > > >>>300+ entries, so it never overflows with legitimate logic. > > ;-) > > > > >>> > > > > >>>Greg Woodhouse wrote: > > > > >>> > > > > >>> > > > > >>> > > > > >>>>It means there was an intepreter stack overflow. :-) > > > > >>>> > > > > >>>>Actually, I think you got into an infinite loop making > > repeated > > > > >>>> > > > > >>>> > > > > >>>routine > > > > >>> > > > > >>> > > > > >>>>calls (each of which requires the allocation of a new stack > > > > frame, > > > > >>>>which contains such details as NEW variables and the return > > > > >>>> > > > > >>>> > > > > >>>address). > > > > >>> > > > > >>> > > > > >>>>--- "Naik, Chintan (EDS)" <[EMAIL PROTECTED]> wrote: > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>>>Anyone know what this error means? > > > > >>>>> > > > > >>>>>%DSM-E-STKOVR, Interpreter stack overflow > > > > >>>>> > > > > >>>>> > > > > >>>>>Thanks, > > > > >>>>> > > > > >>>>>Chintan Naik > > > > >>>>>Health System Design & Development > > > > >>>>>* (972)-796-2414 - (Plano - Tue, Wed, Thu) > > > > >>>>>* (817)-798-0546 - (Dallas OIFO - Mon, Fri) > > > > >>>>>* Fax: (972)-796-6181 > > > > >>>>>* mailto:[EMAIL PROTECTED] > > > > >>>>> > > > > >>>>>To care for him who shall have borne the battle and for his > > > > widow > > > > >>>>> > > > > >>>>> > > > > >>>and > > > > >>> > > > > >>> > > > > >>>>>his orphan... Abraham Lincoln > > > > >>>>> > > > > >>>>>Enrollment Systems Group... Where VA Health Care Begins! > > > > >>>>> > > > > >>>>> > > > > >>>>> > > > > >>>>> > > > > >>>>>------------------------------------------------------- > > > > >>>>>SF email is sponsored by - The IT Product Guide > > > > >>>>>Read honest & candid reviews on hundreds of IT Products from > > > > real > > > > >>>>>users. > > > > >>>>>Discover which products truly live up to the hype. Start > > > reading > > > > >>>>> > > > > >>>>> > > > > >>>now. > > > > >>> > > > > >>> > > > > >>>>>http://ads.osdn.com/?ad_ide95&alloc_id396&op=click > > > > >>>>>_______________________________________________ > > > > >>>>>Hardhats-members mailing list > > > > >>>>>[email protected] > > > > > > >>>>>https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > >>>>> > > > > >>>>> > > > > >>>>> > > > > >>>>> > > > > >>>>> > > > > >>>>===== > > > > >>>>A practical man is a man who practices the errors of his > > > > >>>> > > > > >>>> > > > > >>>forefathers. --Benjamin Disraeli > > > > >>> > > > > >>> > > > > >>>>==== > > > > >>>>Greg Woodhouse > > > > >>>>[EMAIL PROTECTED] > > > > >>>>[EMAIL PROTECTED] > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>>------------------------------------------------------- > > > > >>>>SF email is sponsored by - The IT Product Guide > > > > >>>>Read honest & candid reviews on hundreds of IT Products from > > > real > > > > >>>> > > > > >>>> > > > > >>>users. > > > > >>> > > > > >>> > > > > >>>>Discover which products truly live up to the hype. Start > > > reading > > > > >>>> > > > > >>>> > > > > >>>now. > > > > >>> > > > > >>> > > > > >>>>http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > > > >>>>_______________________________________________ > > > > >>>>Hardhats-members mailing list > > > > >>>>[email protected] > > > > >>>>https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>>> > > > > >>===== > > > > >>A practical man is a man who practices the errors of his > > > > forefathers. > > > > >>--Benjamin Disraeli > > > > >>==== > > > > >>Greg Woodhouse > > > > >>[EMAIL PROTECTED] > > > > >>[EMAIL PROTECTED] > > > > >> > > > > >> > > > > >> > > > > >> > > > > >> > > > > >>------------------------------------------------------- > > > > >>SF email is sponsored by - The IT Product Guide > > > > >>Read honest & candid reviews on hundreds of IT Products from > > real > > > > >>users. > > > > >>Discover which products truly live up to the hype. Start > > reading > > > > now. > > > > >>http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > > > >>_______________________________________________ > > > > >>Hardhats-members mailing list > > > > >>[email protected] > > > > >>https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > >> > > > > >> > > > > >> > > > > > > > > > > > > > > >===== > > > > >A practical man is a man who practices the errors of his > > > > forefathers. --Benjamin Disraeli > > > > >==== > > > > >Greg Woodhouse > > > > >[EMAIL PROTECTED] > > > > >[EMAIL PROTECTED] > > > > > > > > > > > > > > > > > > > > > > > > > > > > > >------------------------------------------------------- > > > > >SF email is sponsored by - The IT Product Guide > > > > >Read honest & candid reviews on hundreds of IT Products from > > real > > > > users. > > > > >Discover which products truly live up to the hype. Start reading > > > > now. > > > > >http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > > > >_______________________________________________ > > > > >Hardhats-members mailing list > > > > >[email protected] > > > > >https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > > > > > > > > > > > > > > > > > > > > > > > > > ===== > > > A practical man is a man who practices the errors of his > > forefathers. > > > --Benjamin Disraeli > > > ==== > > > Greg Woodhouse > > > [EMAIL PROTECTED] > > > [EMAIL PROTECTED] > > > > > > > > > > > > > > > > > > ------------------------------------------------------- > > > SF email is sponsored by - The IT Product Guide > > > Read honest & candid reviews on hundreds of IT Products from real > > > users. > > > Discover which products truly live up to the hype. Start reading > > now. > > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > > _______________________________________________ > > > Hardhats-members mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > > > > > > ===== > > A practical man is a man who practices the errors of his forefathers. > > --Benjamin Disraeli > > ==== > > Greg Woodhouse > > [EMAIL PROTECTED] > > [EMAIL PROTECTED] > > > > > > > > > > > > ------------------------------------------------------- > > SF email is sponsored by - The IT Product Guide > > Read honest & candid reviews on hundreds of IT Products from real > > users. > > Discover which products truly live up to the hype. Start reading now. > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > _______________________________________________ > > Hardhats-members mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/hardhats-members > > > > > ===== > A practical man is a man who practices the errors of his forefathers. > --Benjamin Disraeli > ==== > Greg Woodhouse > [EMAIL PROTECTED] > [EMAIL PROTECTED] > > > > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > Hardhats-members mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/hardhats-members > ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Hardhats-members mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hardhats-members
