On Mon, 30 Aug 2010, Joost van der Sluis wrote:
for possibly thousands of arguments in an interface description is simply not
an option.
There is no need to add an {$ifdef windows} to the definition of
QueryInterface. Because on windows/stdcall record-parameters with a
size>pointersize are already passed by value. (Borland did this probably
just for this case) So when we use 'constref' effectively nothing
changes on Windows.
The problem with the {$ifdef}'s does only exist for other header
conversions. (For example the Gecko headers)
And Michael, this is all important for Gecko because all objects are
passed as interfaces. And Gecko uses QueryInterface to 'cast' one
interface to the other, so QueryInterface is called by Gecko a lot. Then
these calls have to be binary compatible.
Changing the definition of QueryInterface to something completely
different is also hard, because now you can do:
Object.QueryInterface(IInterface, AInterfaceInstance);
This is used a lot...
Conclusion(?)
I think that adding 'constref' is the best way to go. It's more
'pascalish', imho. And it has a clear meaning and use, namely converting
'typename const *' definitions from C-headers.
Like I wrote in my last reply to Jonas: I agree that this is the best way to go.
It just means that the gecko interface will need some {$ifdefs} because Delphi
does not support constref.
Michael.
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