Re: [fpc-pascal] Re: pchar with more than 255 characters
Am 13.11.2011 17:49, schrieb Graeme Geldenhuys:
On 13/11/2011, leledumboleledumbo_cool@ wrote:
I think the
compiler treats functions receiving array of char (or pointer to it) as
ShortString when none of the directives above exist.
Indeed, FPC defaults to ShortString if {$H+} is not specified. That is
probably the problem. I really don't know why this is still so (maybe
some performance thing inside the compiler itself). I now simply
specify $H+ in the fpc.cfg file, in case I forget to add it to the
header of a unit.
That the compiler uses ShortString for performance reasons is not
related to the fact that ObjFPC uses them by default. In this case the
reason is simply backwards compatibilty (note: not Delphi compatibilty
:P ). Though its not the compiler which is the problem here as it has an
explicit {$H-} in its define include file.
Regards,
Sven
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Re: [fpc-pascal] Makeskel error or error behind keyboard?
Am 14.11.2011 17:11, schrieb Reinier Olislagers:
Snippet of the code in question:
{ TCustomXMLXSDExporter }
TCustomXMLXSDExporter = class(TCustomFileExporter)
const
DefaultDatasetName = 'Table1';== this is where it bombs
// Name used for the exported table/dataset if no other name can be
found.
private
FANode: TDOMNode; //Just a placeholder for a node which can be reused
Am I doing something wrong or is makeskel in error?
Perhaps the parser does not yet support the declarations inside
classes feature?
Regards,
Sven
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Re: [fpc-pascal] Makeskel error or error behind keyboard?
On Tue, 15 Nov 2011, Sven Barth wrote:
Am 14.11.2011 17:11, schrieb Reinier Olislagers:
Snippet of the code in question:
{ TCustomXMLXSDExporter }
TCustomXMLXSDExporter = class(TCustomFileExporter)
const
DefaultDatasetName = 'Table1';== this is where it bombs
// Name used for the exported table/dataset if no other name can be
found.
private
FANode: TDOMNode; //Just a placeholder for a node which can be reused
Am I doing something wrong or is makeskel in error?
Perhaps the parser does not yet support the declarations inside classes
feature?
It does not support this.
I am working on it, but I need to refactor a large part of the parser.
Michael.
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Re: [fpc-pascal] CloseThread needed? still unclear
Am 14.11.2011 02:32, schrieb nore...@z505.com: First I thought I would post this to the mailing list to ask you what the proper way to program with threads is. If we must call closethread on MS Win machines but not unix machines, then something needs to change to make the threading in the RTL more cross platform (and all the docs would need to mention things about closethread if it is needed). The bug was already mentioned here http://mantis.freepascal.org/view.php?id=13160 and fixed for 2.2.2. CloseThread was implemented in a cross platform way. Regards, Sven ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Makeskel error or error behind keyboard?
On 15-11-2011 9:50, michael.vancann...@wisa.be wrote: On Tue, 15 Nov 2011, Sven Barth wrote: Am 14.11.2011 17:11, schrieb Reinier Olislagers: Snippet of the code in question: TCustomXMLXSDExporter = class(TCustomFileExporter) const DefaultDatasetName = 'Table1';== this is where it bombs Am I doing something wrong or is makeskel in error? Perhaps the parser does not yet support the declarations inside classes feature? It does not support this. I am working on it, but I need to refactor a large part of the parser. Michael. Ok, thanks, Reinier ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] parent class as a parameter type
On 12.11.2011 22:18, ik wrote: Since 2.6.0, when you write something like this: procedure foo(AClass : TStrings); foo(MyStringList); // Will return an error that TStrings is expected ... That would be strange indeed, because then most events (onclick handlers etc) would not compile anymore, since they are in the format procedure(Sender: TObject) of object... Bart ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] parent class as a parameter type
On Tue, Nov 15, 2011 at 10:10 AM, Bart bartjun...@gmail.com wrote: That would be strange indeed, because then most events (onclick handlers etc) would not compile anymore, since they are in the format procedure(Sender: TObject) of object... It is not like that, he forgot adding var or out to the parameter. The example which you are mentioning has no var. -- Felipe Monteiro de Carvalho ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] parent class as a parameter type
On 15/11/2011, Felipe Monteiro de Carvalho felipemonteiro.carva...@gmail.com wrote: On Tue, Nov 15, 2011 at 10:10 AM, Bart bartjun...@gmail.com wrote: That would be strange indeed, because then most events (onclick handlers etc) would not compile anymore, since they are in the format procedure(Sender: TObject) of object... It is not like that, he forgot adding var or out to the parameter. The example which you are mentioning has no var. Indeed. I checked my code and Delphi 5-7 compatibility. The problem I had, wast that I specified those parameters as var. -- Regards, - Graeme - ___ fpGUI - a cross-platform Free Pascal GUI toolkit http://fpgui.sourceforge.net ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
[fpc-pascal] various ways of passing a class instance as a parameter
Hi,
What exactly is the difference (if any) between the parameter modifier
when you pass a class instance to a procedure?
In the example below, I can define foo() as follows...
procedure foo(AClass: TStringList);
or
procedure foo(var AClass: TStringList);
or
procedure foo(const AClass: TStringList);
...and the program output is always the same. As in the first case
where I don't specify var or const, how does FPC treat the AClass
parameter?
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
program a;
{$mode objfpc}{$H+}
uses
Classes;
procedure foo(AClass: TStringList);
begin
AClass.Add('inside foo');
end;
var
sl: TStringList;
begin
sl := TStringList.Create;
try
sl.Add('inside main');
foo(sl);
sl.Add('the end');
writeln(sl.Text);
finally
sl.free;
end;
end.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Here is the program output:
$ ./a
inside main
inside foo
the end
--
Regards,
- Graeme -
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Re: [fpc-pascal] Re: pchar with more than 255 characters
On 15/11/2011, Sven Barth pascaldra...@googlemail.com wrote: In this case the reason is simply backwards compatibilty (note: not Delphi compatibilty :P ). But that's my point. I really don't think anybody is writing TP style programs any more. So wouldn't it make sense to change the default for the vast majority or programs written with FPC today? Mode TP (-Mtp) can default to shortstring and mode Delphi or mode ObjFPC can default to longstrings? Just like I think FPC should default to mode ObjFPC (instead of mode fpc). Though I must admit, I have no idea what the difference are between those modes. -- Regards, - Graeme - ___ fpGUI - a cross-platform Free Pascal GUI toolkit http://fpgui.sourceforge.net ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] various ways of passing a class instance as a parameter
15.11.2011 13:33, Graeme Geldenhuys пишет: Hi, What exactly is the difference (if any) between the parameter modifier when you pass a class instance to a procedure? I your example there is no difference, except that var could be ~0.01% slower ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] various ways of passing a class instance as a parameter
On Tue, 15 Nov 2011, Graeme Geldenhuys wrote: Hi, What exactly is the difference (if any) between the parameter modifier when you pass a class instance to a procedure? It behaves exactly the same as if you would pass a typed pointer. Michael. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] various ways of passing a class instance as a parameter
On Tuesday 15 November 2011 10.33:13 Graeme Geldenhuys wrote: Hi, What exactly is the difference (if any) between the parameter modifier when you pass a class instance to a procedure? In the example below, I can define foo() as follows... procedure foo(AClass: TStringList); or Take a copy of the AClass instance pointer. procedure foo(var AClass: TStringList); Take the address of the instance variable. The instance pointer can be changed by the procedure, so the type of the instance variable must match TStringList exactly otherwise the procedure could store a wrong class into the instance variable. Example: procedure foo(var AClass: TList); begin aclass.free; aclass:= Tlist.create; end; [...] var cl1: TStringList. begin foo(cl1); //does not compile //now there would be a TList in a TstringList variable or procedure foo(const AClass: TStringList); Take a copy of the AClass instance pointer, AClass is readonly. or procedure foo(constref AClass: TStringList); Take the address of the instance variable, AClass is readonly. Martin ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] various ways of passing a class instance as a parameter
On 15/11/2011, Martin Schreiber mse0@g. wrote:
Thanks Martin. Extending my example by changing the body of foo() too...
AClass.Free;
AClass := TStringList.Create;
AClass.Add('inside foo');
...reveals a bit more about the differences.
procedure foo(const AClass: TStringList);
Take a copy of the AClass instance pointer, AClass is readonly.
This one confused me a bit. I thought the whole object would be
read-only, but in fact it is just the AClass instance pointer which
cannot be modified. The properties of AClass are still read-write.
--
Regards,
- Graeme -
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Re: [fpc-pascal] various ways of passing a class instance as a parameter
On Tuesday 15 November 2011 11.00:34 Graeme Geldenhuys wrote: procedure foo(const AClass: TStringList); Take a copy of the AClass instance pointer, AClass is readonly. This one confused me a bit. I thought the whole object would be read-only, but in fact it is just the AClass instance pointer which cannot be modified. The properties of AClass are still read-write. The wording was bad. Should be: procedure foo(AClass: TStringList); or Take a copy of the AClass instance pointer. procedure foo(var AClass: TStringList); Take the address of the instance variable. The instance pointer pointed by the address can be changed by the procedure, so the type of the instance variable must match TStringList exactly otherwise the procedure could store a wrong class into the instance variable. Example: procedure foo(var AClass: TList); begin aclass.free; aclass:= Tlist.create; end; [...] var cl1: TStringList. begin foo(cl1); //does not compile //now there would be a TList in a TstringList variable or procedure foo(const AClass: TStringList); Take a copy of the AClass instance pointer, AClass instance pointer is readonly. or procedure foo(constref AClass: TStringList); Take the address of the instance variable, AClass instance pointer pointed by the address is readonly. Martin ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] Re: pchar with more than 255 characters
Am 15.11.2011 10:39, schrieb Graeme Geldenhuys: On 15/11/2011, Sven Barthpascaldra...@googlemail.com wrote: In this case the reason is simply backwards compatibilty (note: not Delphi compatibilty :P ). But that's my point. I really don't think anybody is writing TP style programs any more. So wouldn't it make sense to change the default for the vast majority or programs written with FPC today? Mode TP (-Mtp) can default to shortstring and mode Delphi or mode ObjFPC can default to longstrings? The backwards compatibilty in this case is not for TP, but for FPC code that uses ObjFPC, but not H+. In the end you need to discuss this with Florian, Jonas or some other senior dev who has the final say for this... Note: mode Delphi already defaults to H+ Just like I think FPC should default to mode ObjFPC (instead of mode fpc). Though I must admit, I have no idea what the difference are between those modes. No classes, no try/except/finally and some other things maybe Regards, Sven ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] pchar with more than 255 characters
On 14 Nov 2011, at 22:08, Felipe Monteiro de Carvalho wrote: On Sun, Nov 13, 2011 at 1:39 AM, Rainer Stratmann rainerstratm...@t-online.de wrote: procedure getchars( p : pchar ); var l : longint; begin l := length( p ); end; You cannot do length in a PChar length(pchar) is translated into strlen(pchar) (just like in Delphi). Jonas ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
[fpc-pascal] SQLDB Firebird port other than 3050
Hi all, This is probably my confused week, but I couldn't find any documentation. How do I specify the port number when connecting to Firebird/Interbase databases with sqldb on a different port than the default (3050)? Thanks, Reinier ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
Re: [fpc-pascal] SQLDB Firebird port other than 3050
On Tue, 15 Nov 2011, Reinier Olislagers wrote: Hi all, This is probably my confused week, but I couldn't find any documentation. How do I specify the port number when connecting to Firebird/Interbase databases with sqldb on a different port than the default (3050)? Try /portnr:/path/to/database in your databasename. Michael. ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
RE : [fpc-pascal] SQLDB Firebird port other than 3050
Hi all, This is probably my confused week, but I couldn't find any documentation. How do I specify the port number when connecting to Firebird/Interbase databases with sqldb on a different port than the default (3050)? Try /portnr:/path/to/database in your databasename. host/port:c:\...\data.fdb http://www.destructor.de/firebird/multiinstance.htm Ludo ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
[fpc-pascal] Re: RE : SQLDB Firebird port other than 3050
On 15-11-2011 16:30, Ludo Brands wrote: How do I specify the port number when connecting to Firebird/Interbase databases with sqldb on a different port than the default (3050)? Try /portnr:/path/to/database in your databasename. host/port:c:\...\data.fdb http://www.destructor.de/firebird/multiinstance.htm Thanks, you 2, that works. In other words, RTFM (the Firebird one, that is) ;) Time for me to get away from this keyboard ;) ___ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
