Hi Tiemo, It is always better to be explicit, and in this case to use a return statement. Note that a shorter function foo1 could be:
function foo1 return foo2() end foo1 As for my post of this morning, my suggestion was certainly too complex. It is sufficient to figure a transitory ‘returnedValue’ generated by the calling script, where it will pick the last value returned. In the case of cascading functions, each return would overwrite the previous ‘returnedValue”. If a return is missing, then the calling script will get the value of the previous one. Jacques > Le 14 nov. 2014 à 17:20, Tiemo Hollmann TB <toolb...@kestner.de> a écrit : > > Hi Craig, > perhaps I didn't expressed myself correct, I'm not a native speaker. > For me the result seems the same, if I put a return myVar2 at the end of > function foo1 or not (see below). The intermediate function is terminated > AFTER the call of the second function at the end. > My original script works without a return in foo1. My question was, if it is > a good or bad practice if I would add this return, just for "safety reasons" > to be sure anything is returned in case I would change anything, e.g. I would > replace the call of function foo2 by any other structure. > Tiemo > > --Btn script > on mouseUp > put foo1() into myVar1 > end mouseUp > > --script in stack > function foo1 > put foo2() into myVar2 > return myVar2 -- return statement yes or no? > end foo1 > > function foo2 > return "Test" > end foo2 > >> -----Ursprüngliche Nachricht----- >> Von: use-livecode [mailto:use-livecode-boun...@lists.runrev.com] Im Auftrag >> von dunb...@aol.com >> Gesendet: Freitag, 14. November 2014 17:00 >> An: use-livecode@lists.runrev.com >> Betreff: Re: how are variables passed from functions? >> >> Hi. >> >> >> Putting intermediate returns will immediately terminate the function call. >> How >> would you reach the next stage? >> >> >> Perhaps this is another "slightly off" aspect of the original example: The >> intermediate variable "myVar2" is only seen in the debugger, and therefore >> only actually "present" at all, when the secondary function returns it s >> value. And even then it is only in passing, you might say, on the way back to >> the primary function call. But this would never complete if you placed a >> return in the primary function handler. >> >> >> Try it. Watch the flow. You HAVE to not return in any of these intermediate >> handlers. >> >> >> Craig >> >> >> >> -----Original Message----- >> From: Tiemo Hollmann TB <toolb...@kestner.de> >> To: 'How to use LiveCode' <use-livecode@lists.runrev.com> >> Sent: Fri, Nov 14, 2014 10:38 am >> Subject: AW: how are variables passed from functions? >> >> >> Hi Craig, >> I wasn't aware of this behaviour. >> I think about more complex functions with a lot of if and else structures, >> where you are perhaps not aware anymore of this function chain after some >> years, when you are changing the first or the second function? >> Would it be a good or at least not a bad practice to put a return in the >> intermediate function? Or could it even break anything if you would >> explicitly >> return myVar2 in the first function? >> Thanks >> Tiemo >> >> >> >>> -----Ursprüngliche Nachricht----- >>> Von: use-livecode [mailto:use-livecode-boun...@lists.runrev.com] Im >> Auftrag >>> von dunb...@aol.com >>> Gesendet: Freitag, 14. November 2014 16:12 >>> An: use-livecode@lists.runrev.com >>> Betreff: Re: how are variables passed from functions? >>> >>> I don't see any anomaly here. Since the intermediate function calls >>> yet another function, it never needs to "close", that is, return, a >>> value. It >> is a >>> pass-through entity, a card carrying member of the chain of handler calls. >>> Step through this variation: >>> >>> >>> >>> on mouseUp >>> put double(2) into myVar1 >>> answer myVar1 >>> end mouseUp >>> >>> >>> function double var >>> put redouble(var * 2) into myVar2 -- no return in this function end >>> double >>> >>> >>> function redouble var >>> return var * 2 >>> end redouble >>> >>> >>> The "8" you get is processed sequentially through the handler path, >>> just >> like >>> bacon. >>> >>> >>> Craig Newman >>> >>> >>> >>> -----Original Message----- >>> From: Tiemo Hollmann TB <toolb...@kestner.de> >>> To: 'How to use LiveCode' <use-livecode@lists.runrev.com> >>> Sent: Fri, Nov 14, 2014 3:47 am >>> Subject: how are variables passed from functions? >>> >>> >>> By accident I noticed that I don't have a return at a certain point of >>> a function but nevertheless the value was passed back without a return >>> to >> the >>> calling handler. >>> >>> I can reproduce the issue to this scenario: >>> >>> >>> >>> --Btn script >>> >>> on mouseUp >>> >>> put foo1() into myVar1 -- I get the value "Test" >>> >>> end mouseUp >>> >>> >>> >>> --script in stack >>> >>> function foo1 >>> >>> put foo2() into myVar2 -- no return in this function >>> >>> end foo1 >>> >>> >>> >>> function foo2 >>> >>> return "Test" -- return here in second level >>> >>> end foo2 >>> >>> >>> >>> Up to now I thought that every function has to have a return statement >>> if you want anything getting back. >>> >>> Can somebody explain to me what is going on here? How is the value >>> from function foo2 passed back to the mouseup handler, even with >>> different var names? >>> >>> Is this a bug or just an accident or even wanted? >>> >>> Thanks for enlightening >>> >>> Tiemo _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
