objects: clearing objects

[jeeswg]

In these two examples, I do a task twice, with/without assigning an object. If I *don't* assign an object, does the object still exist, but without a name, and without being cleared?

Also, in the Explorer example, is it OK just to replace one object with another, or should I really be clearing the object the first, before I assign the same name to a different object.

Thanks for reading.

Code: Select all

q::
MsgBox, % (oArray := StrSplit("a,b,c,d,e", ",")).Length()
MsgBox, % StrSplit("f,g,h,i,j", ",").Length()
MsgBox, % IsObject(oArray)
oArray := ""
return

w::
WinGetClass, vWinClass, A
if !(vWinClass = "CabinetWClass") && !(vWinClass = "ExploreWClass")
	return

for oWin in ComObjCreate("Shell.Application").Windows
	if (oWin.HWND = hWnd)
		break
vDir := oWin.Document.Folder.Self.Path

for oWin in oWindows := ComObjCreate("Shell.Application").Windows
	if (oWin.HWND = hWnd)
		break
vDir := oWin.Document.Folder.Self.Path

MsgBox, % IsObject(oWin) " " IsObject(oWindows)
oWindows := oWin := ""
return

[kon]

As I understand it, AHK implements reference counting. So when you store a reference to an object (in a variable or in another object) the reference count is increased. When you clear the contents of that variable/object, this decrements the reference count. When the reference count reaches zero AHK releases the object.

If I *don't* assign an object, does the object still exist, but without a name, and without being cleared?

To my understanding, the object would be released when the expression finishes evaluating.

Also, in the Explorer example, is it OK just to replace one object with another, or should I really be clearing the object the first, before I assign the same name to a different object.

I think both have the same effect.

[jeeswg]

For functions, do local objects (objects defined within the body of the function) get cleared when the function ends?

@kon: Thanks.

[HotKeyIt]

For functions, do local objects (objects defined within the body of the function) get cleared when the function ends?

@kon: Thanks.

If they are not assigned to a variable or another object they are cleared directly.
If assigned to local variable, before function exits local vars get cleared and objects gets released/deleted (unless you return the object(s)).