Why can't the parameter of "LV_GetText" be "Clipboard"?

[afe]

Hello,
I tried to use "Clipboard" as the OutputVar of "LV_GetText", but it doesn't work. Why?

Thanks.

Code: Select all

LV_GetText(Clipboard, 1)

[evilC]

Clipboard is a reserved variable, and holds (or sets) the contents of the clipboard.
I am not sure you can use it as an OutputVar

[afe]

Is it not also assignable?

[nnnik]

byref is trash thats why.
There are tons of things you can assign to but byref doesn't work on.
(LV_GetText essentially outputs the data using byref)

[afe]

I still can't understand.

[eelrod]

While that doesn't work, here's a workaround:

Code: Select all

LV_GetText( vInfo , 1)
Clipboard := vInfo

[nnnik]

It's an inconsistency within byref.
While you can assign to variables, objects and special variables like Clipboard you cannot pass all of them byref.
See:

Code: Select all

var := ""
obj := []
Clipboard := ""
;These are all valid targets for assignments:
;var, obj.1 or Clipboard

;yet only var can be passed as output parameter:
setToHelloWorld(var)
Msgbox % var ;var now should be Hello World
setToHelloWorld(obj.1)
Msgbox % obj.1 ;should now be Hello World
setToHelloWorld(Clipboard)
Msgbox % Clipboard ;should now be Hello World

;The last 2 messages will not contain Hello World despite the fact that they should.

setToHelloWorld(byref outputParameter) {
	outputParameter := "Hello World"
}

LV_GetText uses byref internally to output to a variable and byref is fundamentally inconsistent and very limited and in general should be avoided unless absolutely needed.

[Helgef]

Byref (udf) has this limitation documented, Outputvar has not, as far as I know. If no one can point to anything in the docs suggesting this is a known limitation, this should be in bug reports.