Re: Great compiler bug! - Comparing events.

From: Andrew Cruickshank (andrew_at_openkast.com)
Date: 10/12/03 

Date: Sun, 12 Oct 2003 21:18:54 +0100

Martin Harvey (Demon Account) wrote:
> On Sun, 12 Oct 2003 19:28:48 +0200, Marjan Venema
> <info@bjmsoftware.OhNoNotThis.com> wrote:
>
>
>>>Unfortunately, the line "if @Event1 = @Event2 then" doesn't compare
>>>the entire event, it only compares the code pointers. Oops!
>>
>>Sunday night may have dampened my brain's efficiency, but why do you
>>expect Delphi to compare entire events when you specifically request
>>address pointers with the @?
>>
>
>
> Because function and method pointers are the one situation where @
> does *NOT* mean take the address of".
>

The OPLG also only says that "@" operator gets the address
of the function or procedure.

You can read it both ways by implication:

   (a) that it will return the instance + method pointer value (64 bits)

or

   (b) that it will return the method pointer only (32 bits)

It looks like the compiler goes with (b). Arguably not a bug. However
it's a nasty little language hack IM(NV)HO.

--------------
Andrew.

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