Michael Van Canneyt het geskryf:
>
> You only need var/out when you want to change the instance pointer, i.e.
> switch to another instance. And I count FreeAndNil() among this. (.Free
> on the other hand is still possible, but not recommended).
>
> If you just want to set properties or call met
Jonas Maebe het geskryf:
>
> This is also documented at http://wiki.freepascal.org/User_Changes_Trunk
> , the first place to look when switching from the fixes branch to trunk.
>
>
Thanks, I bookmarked that link.
Regards,
- Graeme -
--
fpGUI Toolkit - a cross-platform GUI toolkit using F
On Mon, 17 May 2010, Graeme Geldenhuys wrote:
Michael Van Canneyt het geskryf:
You only need var/out when you want to change the instance pointer, i.e.
switch to another instance. And I count FreeAndNil() among this. (.Free
on the other hand is still possible, but not recommended).
If you
On 14/05/2010 15:52, Mattias Gaertner wrote:
"var" means, you can do this:
type
TQStrings = class(TStrings)
end;
procedure A(var s: TStrings);
begin
s:=TQStrings.Create;
end;
Then your TStringList will no longer be a TStringList. That's why 'var'
must match exactly.
Same for out.
Cons
On Mon, 17 May 2010 10:05:27 +0100
Martin wrote:
> On 14/05/2010 15:52, Mattias Gaertner wrote:
> > "var" means, you can do this:
> >
> > type
> >TQStrings = class(TStrings)
> >end;
> >
> > procedure A(var s: TStrings);
> > begin
> >s:=TQStrings.Create;
> > end;
> >
> > Then your TStr
On 17/05/2010 10:29, Mattias Gaertner wrote:
On Mon, 17 May 2010 10:05:27 +0100
Martin wrote:
On 14/05/2010 15:52, Mattias Gaertner wrote:
"var" means, you can do this:
type
TQStrings = class(TStrings)
end;
procedure A(var s: TStrings);
begin
s:=TQStrings.Create;
end;
Hi,
Sorry, I'm still battling with this. My original code looked as follows:
procedure TfpgApplicationBase.CreateForm(AFormClass: TComponentClass; out
AForm: TfpgWindowBase);
begin
try
AForm := TfpgWindowBase(AFormClass.Create(self));
if FMainForm = nil then
FMainForm := AForm;
On Mon, 17 May 2010 10:40:12 +0100
Martin wrote:
> On 17/05/2010 10:29, Mattias Gaertner wrote:
>[...]
> > Theoretically: yes, this could work for classes.
> > But as Jonas explained a few times: 'out' is *not* write only.
> > Out is finalised and must therefore match exactly.
> > And even wr
On Mon, 17 May 2010, Graeme Geldenhuys wrote:
Hi,
Sorry, I'm still battling with this. My original code looked as follows:
procedure TfpgApplicationBase.CreateForm(AFormClass: TComponentClass; out
AForm: TfpgWindowBase);
begin
try
AForm := TfpgWindowBase(AFormClass.Create(self));
if F
Michael Van Canneyt het geskryf:
>
> And correctly so, because you need the OUT: you are modifying the pointer
> and need to pass back the modified pointer to the caller.
Yes, but I can't use OUT because the type of AForm doesn't match exactly -
back to my initial problem when I started with FPC
On 17/05/2010 10:47, Mattias Gaertner wrote:
On Mon, 17 May 2010 10:40:12 +0100
Martin wrote:
On 17/05/2010 10:29, Mattias Gaertner wrote:
[...]
Theoretically: yes, this could work for classes.
But as Jonas explained a few times: 'out' is *not* write only.
Out is finalised and must
On Sat, 2010-05-15 at 22:35 +0200, Den Jean wrote:
> Hi,
>
> make zipinstall does not work for my busybox tar
>
> the call to tar is made like this:
> /bin/tar cfvz /svn/fpc/fpc-2.5.1.arm-linux.tar.gz *
> but my system tar wants the option 'f' right in front of the target filename.
>
> Makefile
Graeme Geldenhuys schrieb:
> Michael Van Canneyt het geskryf:
>> And correctly so, because you need the OUT: you are modifying the pointer
>> and need to pass back the modified pointer to the caller.
>
> Yes, but I can't use OUT because the type of AForm doesn't match exactly -
> back to my initia
On Mon, 17 May 2010 11:41:22 +0200
Graeme Geldenhuys wrote:
>[...]
> Looking at the Lazarus code for Application.CreateForm. Now they do other
> strange things too, creating a instance without calling the constructor
> etc... This doesn't seem like something I want either and still doesn't
> solv
On Saturday 15 May 2010 22:35:23 Den Jean wrote:
> If someone agrees to fix this, I'll make a bug report
>
done
http://bugs.freepascal.org/view.php?id=16504
including patch proposal
___
fpc-devel maillist - fpc-devel@lists.freepascal.org
http://lists.
Hi,
I am investigating why Qt on armel has problems.
I think that one of the problems is
that when c-functions are called from
pascal that the parameters are not passed
correctly (or not as I expected and accommodated for).
I noticed that when the parameter is a
""
like @MyMethod (method of
Florian Klaempfl :
> Graeme Geldenhuys schrieb:
>
> > This compiler change will play havoc on the Simple Factory Method design
> > pattern as well - a base class is used as the parameter type, but
> > descendants are created and passed back. This is a very common case and
> > used a lot.
>
> ...
On Mon, May 17, 2010 at 4:24 PM, Florian Klaempfl
wrote:
>
> ... and one uses normally a function and not a var/out parameter.
No... If you forget to put a variable to receive the function result
(a object created), a memory leak will happen.
The "out" parameter requires a variable.
Marcos Doug
Vinzent Höfler schrieb:
> Florian Klaempfl :
>
>> Graeme Geldenhuys schrieb:
>>
>>> This compiler change will play havoc on the Simple Factory Method design
>>> pattern as well - a base class is used as the parameter type, but
>>> descendants are created and passed back. This is a very common case
On 17/05/2010 22:10, Marcos Douglas wrote:
On Mon, May 17, 2010 at 4:24 PM, Florian Klaempfl
wrote:
... and one uses normally a function and not a var/out parameter.
No... If you forget to put a variable to receive the function result
(a object created), a memory leak will happen.
T
Hello Graeme,
Monday, May 17, 2010, 11:56:29 AM, you wrote:
GG> Yes, but I can't use OUT because the type of AForm doesn't match exactly -
GG> back to my initial problem when I started with FPC 2.5.1.
GG> TfpgWindowBase vs TBulkInvoiceRateListForm type.
So you do not need "out" you need the no
On 17 May 2010 21:59, "Vinzent Höfler" wrote:
> Florian Klaempfl :
>
>> Graeme Geldenhuys schrieb:
>>
>> > This compiler change will play havoc on the Simple Factory Method design
>> > pattern as well - a base class is used as the parameter type, but
>> > descendants are created and passed back. T
Florian Klaempfl :
> Vinzent Höfler schrieb:
> > Florian Klaempfl :
> >
> >> Graeme Geldenhuys schrieb:
> >>
> >>> This compiler change will play havoc on the Simple Factory Method
> design
> >>> pattern as well - a base class is used as the parameter type, but
> >>> descendants are created and p
Henry Vermaak
> On 17 May 2010 21:59, "Vinzent Höfler"
> wrote:
> > Florian Klaempfl :
> >
> >> Graeme Geldenhuys schrieb:
> >>
> >> > This compiler change will play havoc on the Simple Factory Method
> design
> >> > pattern as well - a base class is used as the parameter type, but
> >> > descen
Florian Klaempfl het geskryf:
>
> ... and one uses normally a function and not a var/out parameter.
The design pattern doesn't specify that. The developer can implement it as
they see if. A parameter or a function return type - I have see and used
both methods.
Regards,
- Graeme -
--
fpGUI
Florian Klaempfl het geskryf:
> http://en.wikipedia.org/wiki/Factory_method_pattern
>> Sorry for the sarcasm,
>
> Sarcasm? For sarcasm, you need to have a clue.
No need to be rude.
Maybe I can chip in, because design patterns are right up my alley. Maybe
you forgot, but a design pattern is not
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