On Sun, Mar 6, 2011 at 6:14 AM, Mark Morgan Lloyd <markmll.fpc-pas...@telemetry.co.uk> wrote: > Marcos Douglas wrote: > >>>> Make a function to return a global variable does not make it read only. >>>> If I use your function like this: >>>> o := InitText; >>>> o := nil; //this is the same xInitText = nil >>> >>> Disagree. You are changing the value of o, not of xInitText. xInitText is >>> initialised once somewhere in the unit exporting it, subsequently its >>> properties etc. can be used elsewhere e.g. InitText.AppendFormatted(...). >> >> I was right. >> The "o" points to "xInitText". If you release "o" the "xInitText" will >> be release too. >> But if you do: >> o:=nil >> ...isn't the same xInitText:=nil, of course. > > You're right if you're talking about primitive heap operations, in exactly > the same way that you'd be right if you used assembler to trample all over > flat memory. However sticking to my original question which dealt with > exporting an instance of an object, you could free the read-only object by > doing o.Free which is identical to InitText.Free, i.e. you'd be using the > declared destructor- which presumably could be hidden from calls outside the > exporting unit.
I extrapoled your question... sorry. But my initial concept is OK: your "read only" object is not read only. Marcos Douglas _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
