Thanks very much for the explanation Mark. Regards
Peter > On 21 Sep 2015, at 16:52, Mark Waddingham <m...@livecode.com> wrote: > > Like numbers and strings, arrays are values so they are always (notionally) > copied whenever they move between locations. > > In 7+ this copying is deferred until needed (copy-on-write), prior to 7 they > are copied immediately. > > So, yes, you can pass arrays around without worry. > > Mark. > > Sent from my iPhone > >> On 21 Sep 2015, at 03:28, Peter W A Wood <peterwaw...@gmail.com> wrote: >> >> I understand that arrays are passed by reference in LiveCode not by value. I >> assume that is also that case if you return an array from a function (i.e. >> the reference to the array is returned not its content). When I tried to >> return an array from a function, I found that not only you can do so but >> multiple calls of the function provide different arrays. As the array being >> returned from the function is local to the function, I’m guessing that >> LiveCode is creating a new local array for each function call and returning >> a reference to the local variable. >> >> Here is the code that I ran under LiveCode Server: >> >> function returnArray >> local a >> put 1 into a[1] >> return a >> end returnArray >> >> put returnArray() into b >> put b[1] & return —> prints 1 >> >> put returnArray() into c >> put c[1] & return —> prints 1 >> >> put 3 into c[1] >> >> put b[1] & return —> prints 1 >> put c[1] & return —> prints 2 >> >> Is it safe to use such a technique or will the reference to the array become >> invalid at some stage? >> >> Peter >> >> >> >> >> _______________________________________________ >> 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 > > _______________________________________________ > 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 _______________________________________________ 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
