Re: Great compiler bug! - Comparing events.

From: Martin Harvey (Demon Account) (martin_at_pergolesi.demon.co.uk)
Date: 10/12/03 

Date: Sun, 12 Oct 2003 19:02:42 +0100

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".

Doing:

"if Event1 = Event 2 then" means: "Call both function pointers and
compare the result"

"if @Event1 = @Event 2 then" means: "Compare the value of both
function pointers"

and

"if @@Event1 = @@Event 2 then" means: "Compare the address of both
function pointers"

It's in the OP language guide.

MH.

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