The solution to that is to override the Create methode and have it fire an
assert automatically such as...
constructor TMyGadget.Create;
begin
assert(False, 'Oi! you can't do this, use TMyGadget.CreateBriefly
instead.');
end;
Then create a new protected constructor that the class procedure
CreateBriefly uses...
constructor TMyGadget.HiddenCreate;
begin
inherited Create;
// do stuff
end;
class procedure TMyGadget.CreateBriefly;
var it:TMyGadget;
begin
it:=nil;
try
it:=TMyGadget.HiddenCreate(); //call the protected constructor
finally
it.free;
end;
end;
This way TMyGadget can only be created/used with the CreateBriefly class
procedure and anyone that tries to use it in the traditional sense, using
TMyGadget.Create, will find out pretty quickly how they should be using it.
:)
Nahum
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> Behalf Of Aaron Scott-Boddendijk
> Sent: Friday, October 27, 2000 10:38
> To: Multiple recipients of list delphi
> Subject: Re: [DUG]: Free inside Create
>
>
> > You missed the 'class' part of the class procedure, it should
> be as below
> > with the class reference at the very begining of the statement.
> Good idea
> > though, you get rid of the object trying to free itself within its own
> > constructor which sounds a bit dodgy. :)
>
> > class procedure TMyGadget.CreateBriefly;
> > var it:TMyGadget;
> > begin
> > it:=nil;
> > try
> > it:=TMyGadget.Create(); //call the protected constructor
> > finally
> > it.free;
> > end;
> > end;
>
> The downside is that the 'protected' feature isn't possible as
> create is public in TObject.
> Means that an outsider using your class can still unknowingly do
> a TMyGadet.Create even
> if they're not a descendant.
>
> --
> Aaron Scott-Boddendijk
> INTAZ Limited
> +64 7 838 3371 Voice
> +64 7 838 3372 Fax
>
>
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