[DUG] Is it a bug in latest version of Delphi?

[Jeremy North]

True, but as Joylon correctly points out, you can (in the VCL)
actually cater for the difference in a "real" index out of bounds
error and a LongInt(TObject) typecase returning -1.

It's a bug and should be logged on QC, if it isn't there already.

On Tue, Feb 16, 2010 at 12:50 PM, Kyley Harris <Kyley at harrissoftware.com> wrote:
> interesting
>>    if Longint(Result) = LB_ERR then Error(SListIndexError, Index);
> it would seem that the error is not in delphi at all. Well.. they are simply
> raising the Windows error which say that -1 is the error result for a bad
> index access from windows. if delphi were to ignore this error and you asked
> for the value at index[99] which was out of bounds and you got -1 instead of
> an error I think there would be the same number of complaints from the other
> side.
> Clearly its the windows API that considers -1 invalid.. not delphi.
>
> On Tue, Feb 16, 2010 at 2:24 PM, Karl Reynolds
> <kreynolds at chocfishsoft.co.nz> wrote:
>>
>> On Tue, Feb 16, 2010 at 1:55 PM, Alister Christie
>> <alister at salespartner.co.nz> wrote:
>> > I think the point I was trying to make is that it is that the method
>> > (/array indexer or whatever) was expecting a TObject - passing anything
>> > else could result in unexpected results.
>>
>> Only if you stipulate that you have to remain ignorant of the function
>> internals. The TObject is converted back and forth from a LongInt in
>> order to store it anyway (see GetObject and PutObject).
>>
>> > The fact that -1 doesn't work
>> > is therefor not a bug (unless you can have 1 byte sized objects).
>>
>> var x: longint;
>>
>> x := -1; // Four bytes
>>
>> (May the source be with you).
>>
>> Cheer,
>> Karl
>> _______________________________________________
>> NZ Borland Developers Group - Delphi mailing list
>> Post: delphi at delphi.org.nz
>> Admin: http://delphi.org.nz/mailman/listinfo/delphi
>> Unsubscribe: send an email to delphi-request at delphi.org.nz with Subject:
>> unsubscribe
>
>
>
> --
> Kyley Harris
> Harris Software
> +64-21-671-821
>
> _______________________________________________
> NZ Borland Developers Group - Delphi mailing list
> Post: delphi at delphi.org.nz
> Admin: http://delphi.org.nz/mailman/listinfo/delphi
> Unsubscribe: send an email to delphi-request at delphi.org.nz with Subject:
> unsubscribe
>