On Mon, May 8, 2017 at 10:06 AM, Martin Schreiber <mse00...@gmail.com> wrote: > On Monday 08 May 2017 14:11:28 Marcos Douglas B. Santos wrote: >> On Mon, May 8, 2017 at 2:39 AM, Martin Schreiber <mse00...@gmail.com> wrote: >> >> > One does not need to use "class", it can be removed. I thought that >> >> > people comming from Free Pascal will like it. ;-) >> >> >> >> You could be right, but I think they will like more if not exist >> >> ambiguity. >> >> >> >> :) >> > >> > Other opinions? Should "class" be removed? >> >> Well, if ^TObj is the same as class and you will continue using this >> syntax then, yes, I think class should be removed. >> But maybe we should think more about it. >> > In order to clarify the difference of "object" and "class": > "object" can be allocated on stack or on heap. > "class" is an object which always is allocated on heap -> it always must be > instantiated by a call of a constructor by <classtype>.TheConstructor() and > it must be destroyed by a call of a destructor by > <instancepointer>.TheDestructor() and it has an implicit dereference for > element access. > " > type > objty = object > f1: int32; > f2: int32; > constructor create(); > destructor destroy(); > end; > pobjty = ^objty; > > TObj = class(objty) > end; > > constructor objty.create(); > begin > end; > > destructor objty.destroy(); > begin > end; > > var > obj1: objty; //an instance on stack, needs no create() or destroy() > obj2: ^objty; //on heap > obj3: pobjty; > obj4: TObj; //on heap > begin > obj1.f1:= 123; //no create() call necessary, no destroy() call necessary > > obj2:= objty.create(); > obj2^.f1:= 123; //note the '^' dereference > obj3:= objty.create(); > obj3^.f1:= 123; //note the '^' dereference > obj4:= TObj.create(); > obj4.f1:= 123; //no '^' dereference > obj2.destroy(); > obj3.destroy(); > obj4.destroy(); > "
Ok. Some questions: 1. In this case: obj1: objty; //an instance on stack, needs no create() or destroy() if my object has create() or destroy() they will be executed automatically? 2. In this case: obj2: ^objty; //on heap Is it possible to remove the "^"? obj2.f1:= 123; I think this distinction exists because "class" exists, right? If is possible to remove, well, this is +1 to remove class and mantain just object but without "^" in calls, but we can continue using in definition. What do you think? Marcos Douglas ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ mseide-msegui-talk mailing list mseide-msegui-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mseide-msegui-talk
