Am 16.09.2022 um 03:53 schrieb Hairy Pixels:
On Sep 11, 2022, at 3:28 PM, Ondrej Pokorny via fpc-pascal <fpc-pascal@lists.freepascal.org> wrote: You should be able to get the Invoke procedure pointer from the RTTI.Sorry Sven mentioned this I must have glossed over it. So yes I am storing the function reference in a class so it’s not going to get freed. Given this example here can you explain how to get the procedure pointer from the RTTI? Even so if you get the procedure pointer you need the class instance also, which reference must be keeping somewhere right? type TProc = reference to procedure; TMyClass = class procedure DoThis; end; var p: TProc; c: TMyClass; begin c := TMyClass.Create; p := c.DoThis; // Can I get the refefence to "c" back using the RTTI? end.
No, you can't get a reference to c, because the compiler will essentially create the following code:
=== code begin === type TProc = reference to procedure; TMyClass = class procedure DoThis; end; TCapturer = class(TInterfacedObject, TProc) m: procedure of object; procedure Anonymous1; procedure TProc.Invoke = Anonymous1; end; var p: TProc; c: TMyClass; capturer: TCapturer; capturer_keepalive: IUnknown; begin capturer := TCapturer.Create; capturer_keepalive := capturer; c := TMyClass.Create; capturer.m := @c.DoThis; p := capturer as TProc; end. === code end === Regards, Sven _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal
