Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 8:50 AM, Sven Barth pascaldra...@googlemail.comwrote:

 You need to add a Result.Assign(Self) to your clone call and implement
 a virtually inherited Assign method in each class where you copy all
 fields. This is how TPersistent and its descendants do it as well.


​Yes I added assign, but as example above, it is crashed when creating it

Result:=TBaseObject(ClassType).Create;

-- 
I am using last revision of Lazarus, FPC 2.6 on Windows XP SP3

Best Regards
Zaher Dirkey
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Re: [fpc-pascal] Clone a instance of object

[Michael Van Canneyt]

On Mon, 23 Sep 2013, Zaher Dirkey wrote:


Hi,
I have objects (classes) derived from base one

TBaseObject = class(TObject)
public
   constructor Create; virtual;
   function Clone:TBaseObject;
end;

TMyObject = class(TBaseObject)
   my fields here
end;

o1, o2:TmyObject;
o1  already created;

o2 := o1.Clone;

in Clone i want to create new object from TmyObject but in base object in Clone 
method,like this

TBaseObject.Clone:TBaseObject;
begin
  Result:=TBaseObject(ClassType).Create;//I know it is wrong here
end;


This is wrong. You are typecasting a class reference to an object instance.

The following works:

{$mode objfpc}

Type
  TBaseObject = class(TObject)
  public
  constructor Create; virtual;
  function Clone:TBaseObject;
  end;
  TBaseObjectClass = Class of TBaseObject;

constructor TBaseObject.Create;

begin
end;

Function TBaseObject.Clone:TBaseObject;

Var
  C : TBaseObjectClass;
begin
  C:=TBaseObjectClass(ClassType);
  Result:=C.Create;
end;

Type
  TMyObject = class(TBaseObject)
  //   my fields here
  end;

Var
o1, o2:TmyObject;

begin
  o1:=TMyObject.Create;
  o2 := o1.Clone as TmyObject;
end.

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Re: [fpc-pascal] Clone a instance of object

[patspiper]

On 23/09/13 10:02, Michael Van Canneyt wrote:



This is wrong. You are typecasting a class reference to an object 
instance.


The following works:

{$mode objfpc}

Type
  TBaseObject = class(TObject)
  public
  constructor Create; virtual;
  function Clone:TBaseObject;
  end;
  TBaseObjectClass = Class of TBaseObject;

constructor TBaseObject.Create;

begin
end;

Function TBaseObject.Clone:TBaseObject;

Var
  C : TBaseObjectClass;
begin
  C:=TBaseObjectClass(ClassType);
  Result:=C.Create;
end;

What would happen if Result := Self.ClassType.Create were used instead?


Type
  TMyObject = class(TBaseObject)
  //   my fields here
  end;

Var
o1, o2:TmyObject;

begin
  o1:=TMyObject.Create;
  o2 := o1.Clone as TmyObject;
end.


Stephano
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Re: [fpc-pascal] Clone a instance of object

[Michael Van Canneyt]

On Mon, 23 Sep 2013, patspiper wrote:


On 23/09/13 10:02, Michael Van Canneyt wrote:



This is wrong. You are typecasting a class reference to an object instance.

The following works:

{$mode objfpc}

Type
  TBaseObject = class(TObject)
  public
  constructor Create; virtual;
  function Clone:TBaseObject;
  end;
  TBaseObjectClass = Class of TBaseObject;

constructor TBaseObject.Create;

begin
end;

Function TBaseObject.Clone:TBaseObject;

Var
  C : TBaseObjectClass;
begin
  C:=TBaseObjectClass(ClassType);
  Result:=C.Create;
end;

What would happen if Result := Self.ClassType.Create were used instead?


The wrong constructor would be called. 
Classtype is equivalend to 'Class of TObject'.


The typecast is needed to ensure that the TBaseObject.Create constructor is 
called.
Your basic polymorphism problem...

Michael.
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Re: [fpc-pascal] Incompatible type for generics?

[Xiangrong Fang]

 Short answer: you can't. The same would happen with normal classes.

 Long answer: You could add an additional method Next to your TIntTree
 which returns a TIntTree and just do Result := TIntTree(inherited
 Next); there.

 Why are you subclassing in this case anyway?

Thanks, I will inherit the method.  I need to add features in the
sub-class. This empty TIntTree is just to show the problem.
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Re: [fpc-pascal] bridging an C++ shared library statically

[Michael Schnell]

On 09/21/2013 04:04 PM, Xiangrong Fang wrote:

Hi All,

I need to use a C++ so file in FreePascal


AFAIK, you only can use C++ libraries in Pascal, if the functions for 
the mutual interface are flat C function (i. e. ANSI C functions not 
using any C++ classes). Of course, on top of this in both source codes 
the same ABI spec needs to be defined (e.g. PASCAL or STDCALL).


-Michael

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Re: [fpc-pascal] bridging an C++ shared library statically

[Sven Barth]

Am 23.09.2013 10:53, schrieb Michael Schnell:

On 09/21/2013 04:04 PM, Xiangrong Fang wrote:

Hi All,

I need to use a C++ so file in FreePascal


AFAIK, you only can use C++ libraries in Pascal, if the functions for 
the mutual interface are flat C function (i. e. ANSI C functions not 
using any C++ classes). Of course, on top of this in both source codes 
the same ABI spec needs to be defined (e.g. PASCAL or STDCALL).
You know that he wrote this the following as well (directly after your 
quote ends)?

I have written a C wrapper for it, which successfully connected to Pascal.
He only has problems LINKING the library and here it does not matter 
whether the library is written in C or C++.


Regards,
Sven
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Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
mich...@freepascal.org wrote:

 Var
   C : TBaseObjectClass;
 begin
   C:=TBaseObjectClass(ClassType)**;
   Result:=C.Create;
 end;


​Yes, that help me, thanks.

Now about assigning I must repeat it (assign) for every child class copy
its field members, is there any trick to copy the values like assigning
record var to another record var?
I know it is kind of strange way :P

​Thanks​

​Zaher Dirkey​
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[fpc-pascal] Re: StrUtils.RomanToInt oddities

[Lukasz Sokol]

On 20/09/13 19:49, Bart wrote:
 On 9/20/13, Reinier Olislagers reinierolislag...@gmail.com wrote:
 
 The question however becomes what is the
 algorithm for deciding invalid characters which IMO will become a mess
 very quickly. Much better to just consider the entire input as invalid.

 
 Here's my implementation:

Here is how I would write it ;)

function TryRomanToInt(AInput:String; out AResult: integer):boolean;
var i, Len, N, Np1 : integer;

  function TryRomanCharToInt(AIn: Char; out AOut: integer): boolean;
  begin
case AIn of
  'M' : AOut := 1000;
  'D' : AOut := 500;
  'C' : AOut := 100;
  'L' : AOut := 50;
  'X' : AOut := 10;
  'V' : AOut := 5;
  'I' : AOut := 1;
else
  AOut := 0;
end;
Result := (AOut  0);
  end;

begin
  // if it looks like shameless cp, it's because it is ;)
  Result := False;
  AInput := UpperCase(AInput);  //don't use AnsiUpperCase please
  Len := Length(AInput);
  if (Len = 0) then Exit;
  // 
  i := 1;
  for i := 1 to Len-1 do 
  begin
if not TryRomanCharToInt(AInput[i], N) then
begin
  AResult := -1; // invalidate everything
  exit;
// writeln('Not a valid roman numeral at position ',i);
end;

if (i  Len -1) then 
  begin 
if not TryRomanCharToInt(AInput[i+1], Np1) then
begin
  AResult := -1; // invalidate everithing
  exit;
// writeln('Not a valid roman numeral at position ',i+1);
end;
 
// according to wikipedia, wonder if these are hard or soft rules 
thou...
if not (((N = 100) and (Np1  100)) or  // C can be placed before L or M
((N = 10) and (Np1  10) and (Np1 = 100)) or // X can be 
placed before L or C
((N = 1) and (Np1  1) and (Np1 = 10)))  // I can be placed 
before V and X
then
  begin
AResult := -1; // invalidate everithing: catches MDCLXVIVXLDM
exit;
// writeln('Not a valid roman numeral combination at position ',i, 
' and ',i+1);
  end;
  

if N = Np1 then AResult := AResult + N
else AResult := AResult - N;

  end;
else // i = Len-1 = last char we just add (consider : MCM : add 1000, sub 
100, add 1000 = 1900)
 begin
   AResult := AResult + N;
 end;
  end; // for
  // if the above, after all characters are through, has resulted in 0 or less,
  // we invalidate everything at the end (consider : CMLM, IIIM )
  
  Result := AResult  0;
  if not Result then AResult := 0;
end;

(only mind-compiled ;) tests welcome ;) )

-L

 
 program test;
 
 {$mode objfpc}
 {$H+}
 
 uses
   SysUtils, StrUtils;
 
 
 function TryRomanToInt(S: String; out N: Integer): Boolean;
 var
   i, Len: Integer;
   Terminated: Boolean;
 begin
   Result := (False);
   S := UpperCase(S);  //don't use AnsiUpperCase please
   Len := Length(S);
   if (Len = 0) then Exit;
   i := 1;
   N := 0;
   Terminated := False;
   //leading M's
   while (i = Len) and (S[i] = 'M') do
   begin
 //writeln('TryRomanToInt: Found 1000');
 Inc(i);
 N := N + 1000;
   end;
   //then CM or or CD or D or (C, CC, CCC, )
   if (i = Len) and (S[i] = 'D') then
   begin
 //writeln('TryRomanToInt: Found 500');
 Inc(i);
 N := N + 500;
   end
   else if (i + 1 = Len) and (S[i] = 'C') then
   begin
 if (S[i+1] = 'M') then
 begin
   //writeln('TryRomanToInt: Found 900');
   Inc(i,2);
   N := N + 900;
 end
 else if (S[i+1] = 'D') then
 begin
   //writeln('TryRomanToInt: Found 400');
   Inc(i,2);
   N := N + 400;
 end;
   end ;
   //next max 4 C's
   if (i = Len) and (S[i] = 'C') then
   begin
 //find max 4 C's
 //writeln('TryRomanToInt: Found 100');
 Inc(i);
 N := N + 100;
 if (i = Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
 if (i = Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
 if (i = Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
   end;
 
   //then XC or XL
   if (i + 1 = Len) and (S[i] = 'X') then
   begin
 if (S[i+1] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 90');
   Inc(i,2);
   N := N + 90;
 end
 else if  (S[i+1] = 'L') then
 begin
   //writeln('TryRomanToInt: Found 40');
   Inc(i,2);
   N := N + 40;
 end;
   end;
 
   //then L
   if (i = Len) and (S[i] = 'L') then
   begin
 //writeln('TryRomanToInt: Found 50');
 Inc(i);
 N := N + 50;
   end;
 
   //then (X, xx, xxx, )
   if (i = Len) and (S[i] = 'X') then
   begin
 //find max 4 X's
 //writeln('TryRomanToInt: Found 10');
 Inc(i);
 N := N + 10;
 if (i = Len) and (S[i] = 'X') then
 begin
   //writeln('TryRomanToInt: Found 10');
   

Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 12:46 PM, Michael Van Canneyt 
mich...@freepascal.org wrote:

 There is no such safe mechanism.

 The best you can do is make the properties published, and write an RTTI
 lookup routine that copies all Published values.
 I've done this several times, it works well for most situations.


​It is not the fastest way like assigning a record, can we ask it as a
feature in FPC ?​

Best Regards
Zaher Dirkey
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Re: [fpc-pascal] Clone a instance of object

[Michael Van Canneyt]

On Mon, 23 Sep 2013, Zaher Dirkey wrote:



On Mon, Sep 23, 2013 at 12:46 PM, Michael Van Canneyt mich...@freepascal.org 
wrote:
  There is no such safe mechanism.

  The best you can do is make the properties published, and write an RTTI 
lookup routine that copies all Published values.
  I've done this several times, it works well for most situations.


​It is not the fastest way like assigning a record, can we ask it as a feature 
in FPC ?​


It's impossible to do correctly.

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Re: [fpc-pascal] Clone a instance of object

[Mattias Gaertner]

On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
Michael Van Canneyt mich...@freepascal.org wrote:

 
 
 On Mon, 23 Sep 2013, Zaher Dirkey wrote:
 
  
  On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
  mich...@freepascal.org wrote:
Var
  C : TBaseObjectClass;
begin
  C:=TBaseObjectClass(ClassType);
  Result:=C.Create;
end;
  
  
  ​Yes, that help me, thanks.
  
  Now about assigning I must repeat it (assign) for every child class copy 
  its field members, is there any trick to copy the values like assigning 
  record var to another record
  var?
  I know it is kind of strange way :P
 
 There is no such safe mechanism.

Well, actually there is a safe mechanism. You use a record to store the
class variables. But it looks clumsily:

type
 TMyClass = class(TPersistent)
 private
   type
 TMyClassVars = record
   a,b,c: string;
 end;
 private
   F: TMyClassVars;
 public
   procedure Assign(Source: TPersistent);
   property a: string read F.a write F.a;
 end;

procedure TMyClass.Assign(Source: TPersistent);
begin
  F:=TMyClass(Source).F;
  inherited;
end;

 
 The best you can do is make the properties published, and write an RTTI 
 lookup routine that copies all Published values.
 I've done this several times, it works well for most situations.

Mattias
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Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 12:57 PM, Mattias Gaertner 
nc-gaert...@netcologne.de wrote:

 type
  TMyClass = class(TPersistent)
  private
type
  TMyClassVars = record
a,b,c: string;
  end;
  private
F: TMyClassVars;
  public
procedure Assign(Source: TPersistent);
property a: string read F.a write F.a;
  end;


​But in derived classes fields will not assigned​?

Best Regards
Zaher Dirkey
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Re: [fpc-pascal] Clone a instance of object

[Mattias Gaertner]

On Mon, 23 Sep 2013 12:10:41 +0200
Frederic Da Vitoria davito...@gmail.com wrote:

 2013/9/23 Mattias Gaertner nc-gaert...@netcologne.de
 
  On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
  Michael Van Canneyt mich...@freepascal.org wrote:
 
  
  
   On Mon, 23 Sep 2013, Zaher Dirkey wrote:
  
   
On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
  mich...@freepascal.org wrote:
  Var
C : TBaseObjectClass;
  begin
C:=TBaseObjectClass(ClassType);
Result:=C.Create;
  end;
   
   
Yes, that help me, thanks.
   
Now about assigning I must repeat it (assign) for every child class
  copy its field members, is there any trick to copy the values like
  assigning record var to another record
var?
I know it is kind of strange way :P
  
   There is no such safe mechanism.
 
  Well, actually there is a safe mechanism. You use a record to store the
  class variables. But it looks clumsily:
 
  type
   TMyClass = class(TPersistent)
   private
 type
   TMyClassVars = record
 a,b,c: string;
   end;
   private
 F: TMyClassVars;
   public
 procedure Assign(Source: TPersistent);
 property a: string read F.a write F.a;
   end;
 
  procedure TMyClass.Assign(Source: TPersistent);
  begin
F:=TMyClass(Source).F;
inherited;
  end;
 
 
 This wouldn't clone included objects. I mean: if the object to be cloned
 contains objects, those included objects should probably be cloned too, but
 putting them into a record wouldn't achieve that.

Anything that needs code to create needs code to clone.
You can always creates cases where cloning need special code. But if
you limit yourself you can use some of the existing frameworks like
TReader/TWriter of tiopf.

Mattias
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Re: [fpc-pascal] Re: build a compiler for GO32v2 under Windows 8 (or 7)

[Philippe]

  

sorry ... delayed answer ... I don´t felt very well these days 
and this subject is a bit difficult for me ... but I will give time this
week to read all I received ... and find out a way ... I´ll write later
this week 

any way, I thank you very much all for your help! 

Philippe


On Thu, 19 Sep 2013 22:01:50 +0200, Sven Barth wrote: 

 On
18.09.2013 18:48, Philippe wrote:
 
 (first time I am using the mail
list ... I may do it wrong!) I have a quite big program (now with more
than 200.000 lines), first build with TP7. For example it accesses CGA
memory through absolute address ... Years ago I moved to FPC. And it
compiled ok under Windows 98 then under XP. Now with with a new PC
running Windows 8 ... the compiler bugs. It works fine with small
program  but not with one which executable about 1.5 Mb large (which
is my case, I did not checked till which size it works!).
 
 It's not
necessarily a problem of your executable size, but the problem 
 is the
size/amount of units, because when compiling the compiler needs 
 to
keep all their interface meta-data in RAM.
 
 My program should run
in prompt command window of any MS Windows version (compiling on XP
machine, the executable runs fine on MS Windows 8 machine)
 
 This
will however not work on a 64-bit systems as the NT Virtual DOS 

Machine (ntvdm.exe) is not supported there anymore.

-- 
Philippe
 


Links:
--
[1] mailto:fpc-pascal@lists.freepascal.org
[2]
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
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Re: [fpc-pascal] Problems reading some of the messages from this mailing list

[Sven Barth]

Am 23.09.2013 13:09, schrieb Guillermo Martínez:

Hi,

I'm receiving some of the messages from this mailing list coding in an
odd format: A block of characters and digits without any sense.  For
example, the one I quoted at the end of this mail. Does somebody knows
why?


According to my Thunderbird the message you quoted is of mime type 
multipart/mixed, so it's basically a HTML mail. Maybe that is the problem?


Regards,
Sven
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Re: [fpc-pascal] Clone a instance of object

[Michael Van Canneyt]

On Mon, 23 Sep 2013, Mattias Gaertner wrote:


On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
Michael Van Canneyt mich...@freepascal.org wrote:




On Mon, 23 Sep 2013, Zaher Dirkey wrote:



On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt mich...@freepascal.org 
wrote:
  Var
    C : TBaseObjectClass;
  begin
    C:=TBaseObjectClass(ClassType);
    Result:=C.Create;
  end;


​Yes, that help me, thanks.

Now about assigning I must repeat it (assign) for every child class copy its 
field members, is there any trick to copy the values like assigning record var 
to another record
var?
I know it is kind of strange way :P


There is no such safe mechanism.


Well, actually there is a safe mechanism. You use a record to store the
class variables. But it looks clumsily:

type
TMyClass = class(TPersistent)
private
  type
TMyClassVars = record
  a,b,c: string;
end;
private
  F: TMyClassVars;
public
  procedure Assign(Source: TPersistent);
  property a: string read F.a write F.a;
end;

procedure TMyClass.Assign(Source: TPersistent);
begin
 F:=TMyClass(Source).F;
 inherited;
end;


Yes. But that works only for 'simple' types and still requires you to write 
code.

For the more general case where you can have arrays, classes, interfaces and whatnot as 
fields of your object, there is simply no correct way.


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[fpc-pascal] Nested comments

[Juha Manninen]

I realized FPC supports nested {} comments by default.
SynPdf, a Synopse PDF engine
  http://synopse.info/fossil/wiki?name=PDF+Engine
has '{' characters inside comments but they are not meant as nested comments.

How to turn nested comments off?
I did not find any such option even by using the new advanced (!) All
Options GUI in Lazarus.

Regards,
Juha
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Re: [fpc-pascal] Nested comments

[Michael Van Canneyt]

On Mon, 23 Sep 2013, Juha Manninen wrote:


I realized FPC supports nested {} comments by default.
SynPdf, a Synopse PDF engine
 http://synopse.info/fossil/wiki?name=PDF+Engine
has '{' characters inside comments but they are not meant as nested comments.

How to turn nested comments off?
I did not find any such option even by using the new advanced (!) All
Options GUI in Lazarus.


Use Delphi mode or TP mode.

Michael.
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Re: [fpc-pascal] Problems reading some of the messages from this mailing list

[Tomas Hajny]

On Mon, September 23, 2013 13:22, Sven Barth wrote:
 Am 23.09.2013 13:09, schrieb Guillermo Martínez:
 Hi,

 I'm receiving some of the messages from this mailing list coding in an
 odd format: A block of characters and digits without any sense.  For
 example, the one I quoted at the end of this mail. Does somebody knows
 why?


 According to my Thunderbird the message you quoted is of mime type
 multipart/mixed, so it's basically a HTML mail. Maybe that is the
 problem?

That should not be an issue by itself. The more likely reason is probably
use of 8-bit message (utf-8) without encoding in us-ascii (7-bit)
compatible envelope - typically MIME Quoted Printable (as already used
for the HTML section, but not for the plain text version). Some mail
servers may not allow that and recode the message in MIME Base64 encoding
(which is most likely the text below); while doing that, they should
include this information in the header, but I suspect that this hasn't
happened in the case of Guillermo (this could be checked if he forwards
the received message in attachment - doing this via fpc-other would be
more appropriate than here). Nevertheless, the real solution is probably
for Philippe to configure his e-mail client not to send 8-bit messages
without 7-bit safe encoding).

Tomas


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Re: [fpc-pascal] Clone a instance of object

[patspiper]

On 23/09/13 14:57, Michael Van Canneyt wrote:



On Mon, 23 Sep 2013, Mattias Gaertner wrote:


On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
Michael Van Canneyt mich...@freepascal.org wrote:




On Mon, 23 Sep 2013, Zaher Dirkey wrote:



On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
mich...@freepascal.org wrote:

Var
C : TBaseObjectClass;
begin
C:=TBaseObjectClass(ClassType);
Result:=C.Create;
end;


​Yes, that help me, thanks.

Now about assigning I must repeat it (assign) for every child class 
copy its field members, is there any trick to copy the values like 
assigning record var to another record

var?
I know it is kind of strange way :P


There is no such safe mechanism.


Well, actually there is a safe mechanism. You use a record to store the
class variables. But it looks clumsily:

type
TMyClass = class(TPersistent)
private
type
TMyClassVars = record
a,b,c: string;
end;
private
F: TMyClassVars;
public
procedure Assign(Source: TPersistent);
property a: string read F.a write F.a;
end;

procedure TMyClass.Assign(Source: TPersistent);
begin
F:=TMyClass(Source).F;
inherited;
end;


Yes. But that works only for 'simple' types and still requires you to 
write code.


For the more general case where you can have arrays, classes, 
interfaces and whatnot as fields of your object, there is simply no 
correct way.


Can't the clipboard help in cloning? Similar to the IDE's copy and paste.

Stephano
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Re: [fpc-pascal] Nested comments

[Juha Manninen]

On Mon, Sep 23, 2013 at 3:06 PM, Michael Van Canneyt
mich...@freepascal.org wrote:
 Use Delphi mode or TP mode.

Thanks, it helped.
Actually there already was {$MODE Delphi} in an include file.
Apparently it does not work, it must be in every pascal unit.

This PDF package still does not compile with Lazarus. I will see which
is easier, port it for Lazarus or add embedded font support for
PowerPDF.
If somebody knows a solution for PDF embedded fonts, please tell me.

Regards,
Juha
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Re: [fpc-pascal] Nested comments

[Sven Barth]

Am 23.09.2013 14:28, schrieb Juha Manninen:

On Mon, Sep 23, 2013 at 3:06 PM, Michael Van Canneyt
mich...@freepascal.org wrote:

Use Delphi mode or TP mode.

Thanks, it helped.
Actually there already was {$MODE Delphi} in an include file.
Apparently it does not work, it must be in every pascal unit.
The include needs to be before the interface uses clause. Better before 
the 'interface' keyword. Otherwise the modeswitch inside an include file 
works without problems as the FPC compiler uses that as well. Maybe you 
need to check for warnings...


Regards,
Sven
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Re: [fpc-pascal] Clone a instance of object

[Frederic Da Vitoria]

2013/9/23 Michael Van Canneyt mich...@freepascal.org


 On Mon, 23 Sep 2013, Mattias Gaertner wrote:

  On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
 Michael Van Canneyt mich...@freepascal.org wrote:

  On Mon, 23 Sep 2013, Zaher Dirkey wrote:

  On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
 mich...@freepascal.org wrote:
   Var
 C : TBaseObjectClass;
   begin
 C:=TBaseObjectClass(ClassType)**;
 Result:=C.Create;
   end;

 Yes, that help me, thanks.

 Now about assigning I must repeat it (assign) for every child class
 copy its field members, is there any trick to copy the values like
 assigning record var to another record
 var?
 I know it is kind of strange way :P


 There is no such safe mechanism.


 Well, actually there is a safe mechanism. You use a record to store the
 class variables. But it looks clumsily:

 type
 TMyClass = class(TPersistent)
 private
   type
 TMyClassVars = record
   a,b,c: string;
 end;
 private
   F: TMyClassVars;
 public
   procedure Assign(Source: TPersistent);
   property a: string read F.a write F.a;
 end;

 procedure TMyClass.Assign(Source: TPersistent);
 begin
  F:=TMyClass(Source).F;
  inherited;
 end;


 Yes. But that works only for 'simple' types and still requires you to
 write code.

 For the more general case where you can have arrays, classes, interfaces
 and whatnot as fields of your object, there is simply no correct way.


Isn't there? Maybe it wouldn't be easy, but IIRC Delphi offers something
related to this with TComponents and Streams. This Delphi mechanism I knew
worked only for properties, but I found references that there existed a
wider mechanism in D2010.

-- 
Frederic Da Vitoria
(davitof)

Membre de l'April - « promouvoir et défendre le logiciel libre » -
http://www.april.org
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Re: [fpc-pascal] Clone a instance of object

[Michael Van Canneyt]

On Mon, 23 Sep 2013, Frederic Da Vitoria wrote:



Yes. But that works only for 'simple' types and still requires you to write 
code.

For the more general case where you can have arrays, classes, interfaces and 
whatnot as fields of your object, there is simply no correct way.


Isn't there? Maybe it wouldn't be easy, but IIRC Delphi offers something 
related to this with TComponents and Streams. This Delphi mechanism I knew 
worked only for properties,
but I found references that there existed a wider mechanism in D2010.


There is no GENERAL way.

The RTTI based mechanisms make special assumptions about how to reference 
components, tpersistents and whatnot.

If I have a field that is a stream. How are you going to correctly copy this ? 
Just the stream instance pointer ? The stream+Contents ?


The answer depends on how the classes are supposed to behave. The language 
itself cannot give you this mechanism.

Michael.
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Re: [fpc-pascal] Clone a instance of object

[Sven Barth]

Am 23.09.2013 14:23, schrieb patspiper:

On 23/09/13 14:57, Michael Van Canneyt wrote:



On Mon, 23 Sep 2013, Mattias Gaertner wrote:


On Mon, 23 Sep 2013 11:46:54 +0200 (CEST)
Michael Van Canneyt mich...@freepascal.org wrote:




On Mon, 23 Sep 2013, Zaher Dirkey wrote:



On Mon, Sep 23, 2013 at 10:02 AM, Michael Van Canneyt 
mich...@freepascal.org wrote:

Var
C : TBaseObjectClass;
begin
C:=TBaseObjectClass(ClassType);
Result:=C.Create;
end;


​Yes, that help me, thanks.

Now about assigning I must repeat it (assign) for every child 
class copy its field members, is there any trick to copy the 
values like assigning record var to another record

var?
I know it is kind of strange way :P


There is no such safe mechanism.


Well, actually there is a safe mechanism. You use a record to store the
class variables. But it looks clumsily:

type
TMyClass = class(TPersistent)
private
type
TMyClassVars = record
a,b,c: string;
end;
private
F: TMyClassVars;
public
procedure Assign(Source: TPersistent);
property a: string read F.a write F.a;
end;

procedure TMyClass.Assign(Source: TPersistent);
begin
F:=TMyClass(Source).F;
inherited;
end;


Yes. But that works only for 'simple' types and still requires you to 
write code.


For the more general case where you can have arrays, classes, 
interfaces and whatnot as fields of your object, there is simply no 
correct way.


Can't the clipboard help in cloning? Similar to the IDE's copy and paste.
Even then you'd need to convert the fields to the format the clipboard 
expects. And if you managed to correctly stream all properties than 
you don't need the clipboard anyway...


Regards,
Sven
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[fpc-pascal] Re: Problems reading some of the messages from this mailing list

[Guillermo Martínez]

From: Tomas Hajny xhaj...@hajny.biz
 
 That should not be an issue by itself. The more likely reason is
 probably use of 8-bit message (utf-8) without encoding in us-ascii
 (7-bit) compatible envelope - typically MIME Quoted Printable (as
 already used for the HTML section, but not for the plain text
 version). Some mail servers may not allow that and recode the message
 in MIME Base64 encoding (which is most likely the text below); while
 doing that, they should include this information in the header, but I
 suspect that this hasn't happened in the case of Guillermo (this
 could be checked if he forwards the received message in attachment -
 doing this via fpc-other would be more appropriate than here).
 Nevertheless, the real solution is probably for Philippe to configure
 his e-mail client not to send 8-bit messages without 7-bit safe
 encoding).
 
 Tomas
 

So I can't do anything, can I?

Unfortunatelly there are more users that sends their e-mail that way,
specially chinese ones.

Thanks.
Guillermo Ñuño Martínez.
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Re: [fpc-pascal] Clone a instance of object

[Graeme Geldenhuys]

On 23/09/13 10:46, Michael Van Canneyt wrote:
 I've done this several times, it works well for most situations.

My I also suggest Zaher takes a look at tiOPF's code to see how they
implement class cloning.

Also be careful about the pitfalls of cloning a class. eg: How you want
to handle more complex cases. eg: Cloning a class with a reference to
another class, or cloning a class with an embedded class (field), etc...
tiOPF's implementation allows the developer to decided how such cases
should be handled.

Regard,
  Graeme.


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Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 12:58 PM, Graeme Geldenhuys gra...@geldenhuys.co.uk
 wrote:


 Also be careful about the pitfalls of cloning a class. eg: How you want
 to handle more complex cases. eg: Cloning a class with a reference to
 another class, or cloning a class with an embedded class (field), etc...
 tiOPF's implementation allows the developer to decided how such cases
 should be handled.


​The idea is simply than needs to use a stream or RTTI, it is like a
record, if looked at an object like as a record but it is inheritable.
​Compile can now every object body, and do the assigning as record assign.
​
That's the feature I like to have. ​

Best Regards
Zaher Dirkey
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Re: [fpc-pascal] Clone a instance of object

[Zaher Dirkey]

On Mon, Sep 23, 2013 at 4:28 PM, Zaher Dirkey parm...@gmail.com wrote:

 ​The idea is simply than needs to use a stream or RTTI, it is like a
 record, if looked at an object like as a record but it is inheritable.
 ​Compile can now every object body, and do the assigning as record assign.
 ​
 That's the feature I like to have. ​

 Best Regards


​This is a funny example about what in my mind about what I talk (I know it
is stupid and unsafe)
If you look it is only for the class that not yet inherited yet, and work
only for the top class, but the compiler can guss all inheited/derived
classes and make the same assign.
If some understand it, maybe give more explain.
​-
type
  TmyRec = record
s: string;
i: integer;
  end;
  PmyRec=^TmyRec;

  TmyObj = class(TObject)
s: string;
i: integer;
  end;


procedure TForm1.Button1Click(Sender: TObject);
var
  o1, o2: TmyObj;
begin
  o1 := TmyObj.Create;
  o2 := TmyObj.Create;
  o1.s := 'test1';
  o1.i := 122;
  PmyRec(@o2)^ := PmyRec(@o1)^;
  WriteLn(o2.s);
  WriteLn(o2.i);
end;
​-​

Best Regards
Zaher Dirkey
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Re: [fpc-pascal] Re: Problems reading some of the messages from this mailing list

[Philippe]

  

I changed the webmail configuration to MIME / 8 bits ... I hope it
helps! 

Philippe 

On Mon, 23 Sep 2013 15:06:00 +0200, Guillermo
Martínez wrote: 

 From: Tomas Hajny 
 
 That should not be an
issue by itself. The more likely reason is probably use of 8-bit message
(utf-8) without encoding in us-ascii (7-bit) compatible envelope -
typically MIME Quoted Printable (as already used for the HTML section,
but not for the plain text version). Some mail servers may not allow
that and recode the message in MIME Base64 encoding (which is most
likely the text below); while doing that, they should include this
information in the header, but I suspect that this hasn't happened in
the case of Guillermo (this could be checked if he forwards the received
message in attachment - doing this via fpc-other would be more
appropriate than here). Nevertheless, the real solution is probably for
Philippe to configure his e-mail client not to send 8-bit messages
without 7-bit safe encoding). Tomas
 
 So I can't do anything, can
I?
 
 Unfortunatelly there are more users that sends their e-mail that
way,
 specially chinese ones.
 
 Thanks.
 Guillermo Ñuño
Martínez.
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[2]
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[3]
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Bart]

On 9/23/13, Lukasz Sokol el.es...@gmail.com wrote:

 function TryRomanToInt(AInput:String; out AResult: integer):boolean;
 var i, Len, N, Np1 : integer;
[snip]


 if N = Np1 then AResult := AResult + N
 else AResult := AResult - N;

   end;
 else // i = Len-1 = last char we just add (consider : MCM : add 1000,

Compiler doesn't like the else here. I removed the ; after the end 1 line above.

 sub 100, add 1000 = 1900)
  begin
AResult := AResult + N;
  end;
   end; // for
   // if the above, after all characters are through, has resulted in 0 or
 less,
   // we invalidate everything at the end (consider : CMLM, IIIM )

   Result := AResult  0;
   if not Result then AResult := 0;
 end;

 (only mind-compiled ;) tests welcome ;) )


It produces odd output though:

C:\Users\Bart\LazarusProjecten\ConsoleProjectentest
Enter Roman numeral: LL  //should be illegal
TryRomanToInt('LL') - 50
StrUtils.RomanToInt('LL') = 100

Enter Roman numeral: MM
TryRomanToInt('MM') - 1050  //obviously should be 2000
StrUtils.RomanToInt('MM') = 2000

Enter Roman numeral: II
TryRomanToInt('II') - 1051  // nice one!
StrUtils.RomanToInt('II') = 2

So, it's a little bit flawed.

Anyhow, let's not focus upon what the new code should be.
The question was: is current behaviour (accepting IIMIIC etc.) a bug or not.

Bart
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

Premise: I didn't go through your entire implementation, thou' at first 
sight looks much better than the current one.


I know roman numerals since I was 8 or 9 yo, that makes a quick and dirt 
result of about 35 years.


Thing is:

1. in the roman numerals, not all the digits can be subtracted from the 
others

2. no more than three same roman numerals can appear in a row.

so that XM is as invalid as .
(although this amenity can be seen on some - in my opinion poor - 
wristwatches' face that uses roman numerals, for the 4h, showing  
instead of the correct IV, but this is another story)


in roman numerals we have only these digits:

I(1)   V(5)
X(10)  L(50)
C(100) D(500)
M(1000) (sorry, no digit for the expected progression, for 5000)

the only digits that can be subtracted are I, X and C (only those on the 
left side of the table above), and they can only from the 2 digits 
immediately following them in the system, so that:


I can be subtracted only from V and X
X can be subtracted only from L and C
C can be subtracted only from D and M

so that 45 cannot be written as VL (50 - 5, as one might suspect) but 
must be written as XLV, or to better understand, as (XL)V = 40 + 5


The maximum roman numeral that can be represented is 4999, that is NOT 
MMMIM, but instead: MMM(CM)(XC)(IX) 
1000+1000+1000+(1000-900)+(100-10)+(10-1)


After this, roman numerals always begin with bigger numbers to sum up, 
and proceed to smaller, so you cannot start adding up 10, then 500, then 
again 1; like XDI (whether it be intended to be 491 or 511 - just no way)


I did an implementation some time ago, for pure fun, and provided I find 
it out (or maybe I can just rewrite it, on the basis of this knowledge) 
I will be - repository allowing ;-) - wery happy to contribute with my 
2c for it.



Cheers, A.


On 20/09/13 21:49, Bart wrote:

On 9/20/13, Reinier Olislagersreinierolislag...@gmail.com  wrote:


The question however becomes what is the
algorithm for deciding invalid characters which IMO will become a mess
very quickly. Much better to just consider the entire input as invalid.



Here's my implementation:

program test;

{$mode objfpc}
{$H+}

uses
   SysUtils, StrUtils;


function TryRomanToInt(S: String; out N: Integer): Boolean;
var
   i, Len: Integer;
   Terminated: Boolean;
begin
   Result := (False);
   S := UpperCase(S);  //don't use AnsiUpperCase please
   Len := Length(S);
   if (Len = 0) then Exit;
   i := 1;
   N := 0;
   Terminated := False;
   //leading M's
   while (i= Len) and (S[i] = 'M') do
   begin
 //writeln('TryRomanToInt: Found 1000');
 Inc(i);
 N := N + 1000;
   end;
   //then CM or or CD or D or (C, CC, CCC, )
   if (i= Len) and (S[i] = 'D') then
   begin
 //writeln('TryRomanToInt: Found 500');
 Inc(i);
 N := N + 500;
   end
   else if (i + 1= Len) and (S[i] = 'C') then
   begin
 if (S[i+1] = 'M') then
 begin
   //writeln('TryRomanToInt: Found 900');
   Inc(i,2);
   N := N + 900;
 end
 else if (S[i+1] = 'D') then
 begin
   //writeln('TryRomanToInt: Found 400');
   Inc(i,2);
   N := N + 400;
 end;
   end ;
   //next max 4 C's
   if (i= Len) and (S[i] = 'C') then
   begin
 //find max 4 C's
 //writeln('TryRomanToInt: Found 100');
 Inc(i);
 N := N + 100;
 if (i= Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
 if (i= Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
 if (i= Len) and (S[i] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 100');
   Inc(i);
   N := N + 100;
 end;
   end;

   //then XC or XL
   if (i + 1= Len) and (S[i] = 'X') then
   begin
 if (S[i+1] = 'C') then
 begin
   //writeln('TryRomanToInt: Found 90');
   Inc(i,2);
   N := N + 90;
 end
 else if  (S[i+1] = 'L') then
 begin
   //writeln('TryRomanToInt: Found 40');
   Inc(i,2);
   N := N + 40;
 end;
   end;

   //then L
   if (i= Len) and (S[i] = 'L') then
   begin
 //writeln('TryRomanToInt: Found 50');
 Inc(i);
 N := N + 50;
   end;

   //then (X, xx, xxx, )
   if (i= Len) and (S[i] = 'X') then
   begin
 //find max 4 X's
 //writeln('TryRomanToInt: Found 10');
 Inc(i);
 N := N + 10;
 if (i= Len) and (S[i] = 'X') then
 begin
   //writeln('TryRomanToInt: Found 10');
   Inc(i);
   N := N + 10;
 end;
 if (i= Len) and (S[i] = 'X') then
 begin
   //writeln('TryRomanToInt: Found 10');
   Inc(i);
   N := N + 10;
 end;
 if (i= Len) and (S[i] = 'X') then
 begin
   //writeln('TryRomanToInt: Found 10');
   Inc(i);
   N := N + 10;
 end;
   end;

   //then IX or IV
   if (i + 1= Len) and (S[i] = 'I') then
   begin
 if (S[i+1] = 'X') then
 begin
   Terminated := (True);
   

Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

Ooops,

I also forgot to mention that only I, X, C and M can appear up to three 
times in a row. V, L and D does not; they can only once.



Cheers again, A.
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Sven Barth]

On 23.09.2013 21:17, Alberto Narduzzi wrote:

Ooops,

I also forgot to mention that only I, X, C and M can appear up to three
times in a row. V, L and D does not; they can only once.


Are you sure regarding M considering there is no symbol for 5000? Or 
didn't Romans count to more than 5000 - 1?


Regards,
sven

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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Bart]

On 9/23/13, Alberto Narduzzi albertonardu...@yahoo.com wrote:

 Thing is:

 1. in the roman numerals, not all the digits can be subtracted from the
 others
 2. no more than three same roman numerals can appear in a row.

My implementation is a little more relaxed as to rule 2.
It is more often violated than rule 1.
Typically  is not al that uncommon.


 I did an implementation some time ago, for pure fun, and provided I find
 it out (or maybe I can just rewrite it, on the basis of this knowledge)
 I will be - repository allowing ;-) - wery happy to contribute with my
 2c for it.

By all means.
The princial question must be answered first though.

Bart
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Bart]

On 9/23/13, Sven Barth pascaldra...@googlemail.com wrote:

 Are you sure regarding M considering there is no symbol for 5000? Or
 didn't Romans count to more than 5000 - 1?


There are numerous extensions upon the scheme.
In later times adding horizontal lines above or under a Roman numeral
meant multiply by 1000.

I don't believe though Romans knew negative numbers.
But I'm certainly not an expert on the matter.

Bart
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Frederic Da Vitoria]

2013/9/23 Bart bartjun...@gmail.com

 The question was: is current behaviour (accepting IIMIIC etc.) a bug or
 not.


What about making an option of it?

Anyhow, if the function accepts invalid combinations, what should it
return? For some, the answer would be obvious (), but some combinations
are indeed ambiguous (M) So that we maybe could accept unambiguous
invalid combinations, but I don't see how to accept ambiguous ones.

-- 
Frederic Da Vitoria
(davitof)

Membre de l'April - « promouvoir et défendre le logiciel libre » -
http://www.april.org
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Bart]

On 9/23/13, Frederic Da Vitoria davito...@gmail.com wrote:

 What about making an option of it?

It's up to the fpc devels.

 Anyhow, if the function accepts invalid combinations, what should it
 return? For some, the answer would be obvious (), but some combinations
 are indeed ambiguous (M) So that we maybe could accept unambiguous
 invalid combinations, but I don't see how to accept ambiguous ones.

If it accepts, then it should apply the subtraction rule: only the
(one) numeral left to the other (bigger one) can be subtracted.
So IIIM would be III + IM = 3 + 1000-1 = 1002 (and not 1000-3 = 997)
There should be no ambiguity there, it's only a pain to watch it.

Bart
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Re: [fpc-pascal] FPCUnit test + raise E;

[Marcos Douglas]

On Thu, Sep 19, 2013 at 1:44 AM, Sven Barth pascaldra...@googlemail.com wrote:
 Am 18.09.2013 23:34 schrieb Marcos Douglas m...@delfire.net:



 On Tue, Sep 17, 2013 at 2:41 PM, Sven Barth pascaldra...@googlemail.com
 wrote:
  On 17.09.2013 17:27, Marcos Douglas wrote:
 
  On Tue, Sep 17, 2013 at 12:18 PM, Marcos Douglas m...@delfire.net
  wrote:
 
  Another thing you could try (just for testing): change your exception
  handler procedure to a function that returns bool and use it like
  this:
 
  === code begin ===
 
 
  procedure TghSQLConnector.Connect;
  begin
 try
   FLib.Connect;
 except
   on E: Exception do
 if not DoOnException(E) then
   raise;
 end;
  end;
 
  === code end ===
 
 
  Regards,
  Sven
 
 
  The only difference is the use of raise; instead raise E; right?
 
  Marcos Douglas
 
 
  In project in attachment before, if you change the line 50
  from:
   raise E;
 
  to:
   raise Exception.Create(E.Message);
 
  Will work... but is this correct?
 
 
  So this seems to be indeed a problem of freeing exceptions. Whether you
  misuse the exception system or you encountered a bug needs to be
  determined...

 If this is a bug I can register in bug tracker.

 I don't know yet whether it's a bug or a mistake...


  Lazarus 1.1 r42461 FPC 2.6.2 i386-win32-win32/win64
 
 
  Could you test your original one with 2.7.1 as well?

 I can't compile Lazarus with FPC 2.7.1 (as you saw in lazarus-list)
 so, I can't test...  :(

 It's ok if you use a 2.7.1 before the merge of the cpstrrtl branch. There
 AFAIK weren't any exception related changes since then.

For now I resolved use re-raise the original Exception using FPC 2.6.2.

Thank you again.

Marcos Douglas
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

What about making an option of it?



If it accepts, then it should apply the subtraction rule: only the
(one) numeral left to the other (bigger one) can be subtracted.
So IIIM would be III + IM = 3 + 1000-1 = 1002 (and not 1000-3 = 997)
There should be no ambiguity there, it's only a pain to watch it.


as I said, roman numerals what they are.

If you want to invent something new, nowadays, extending the roman 
numerals to your like, well (growl!) feel free to do it, but do not 
pretend to call them so.


IIIM has no meaning in roman numerals. FULL STOP. There is no such logic 
as you depict it. 1002 = MII, and 997 = CMXCVII.

All the rest is pure bull in terms of roman numerals by the very name.

I begin to have a feeling that here somebody is merely talking nonsense; 
say, like pretending to use the digit 2 in the binary system...


This is no decimal notation logic; things are as they are, so do not 
pretend to give roman numerals a value according to their position in 
the number itself; it is pure NONSENSE here.


Or maybe you have no clue about, so do not litter Pascal with something 
you don't know anything about, which will only make you just ridicule; 
possibly (hope not, thou') by the very Embarcadero/Delphi guys... which 
is not so good for Freepascal, really.


Ah, BTW, what Delphi does (as I read maybe on the very first reply to 
the topic, sic), here, makes no sense too. Roman numerals are what they 
are, irrelevantly of what somebody *may think they are*.



A.
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

What about making an option of it?

Anyhow, if the function accepts invalid combinations, what should it
return? For some, the answer would be obvious (), but some
combinations are indeed ambiguous (M) So that we maybe could accept
unambiguous invalid combinations, but I don't see how to accept
ambiguous ones.


they are not ambiguous, they are simply INVALID.
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

Are you sure regarding M considering there is no symbol for 5000? Or
didn't Romans count to more than 5000 - 1?


yes I am. as 5000 - 1 would need to be written CMXCIX, which has the 
4-M-in-a-row, that is invalid, as a maximum of three is allowed.


Yes, probably ancient Romans had no need to count more that 3999 
Sestertiae ;-)



I don't believe though Romans knew negative numbers.
But I'm certainly not an expert on the matter.


never though about, but if the only matter is DEBT, then just write 
positive numbers under the DEBT column, and everybody shall be happy 
too, provided they know the meaning of such a column ;-)


P.S.
Have no clue of roman arithmetics, thou', which looks a little more 
weird to implement, or just to think about :-O



A.
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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Martin]

On 23/09/2013 22:30, Alberto Narduzzi wrote:

What about making an option of it?

Anyhow, if the function accepts invalid combinations, what should it
return? For some, the answer would be obvious (), but some
combinations are indeed ambiguous (M) So that we maybe could accept
unambiguous invalid combinations, but I don't see how to accept
ambiguous ones.


they are not ambiguous, they are simply INVALID.


So the question is, what does or should do RomanToInt for invalid input?

It is NOT called CheckValidRoman, so it could be that the result for 
invalid input is simply undefined. If it is, then all is ok.

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Re: [fpc-pascal] Re: StrUtils.RomanToInt oddities

[Alberto Narduzzi]

So the question is, what does or should do RomanToInt for invalid input?

It is NOT called CheckValidRoman, so it could be that the result for
invalid input is simply undefined. If it is, then all is ok.


so, what does 10AT (or $10AT for tht matter) return for HexToDec??? 
maybe NaN, if there is such a definition in Pascal??? Looks acceptable 
to me.


But IsValidRoman is as good as a solution too, indeed...
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Re: [fpc-pascal] Problems reading some of the messages from this mailing list

[wkitty42]

On Monday, September 23, 2013 7:09 AM, Guillermo Martínez 
gmarti...@burdjia.com wrote: 
 Hi, 
  
 I'm receiving some of the messages from this mailing list coding in an 
 odd format: A block of characters and digits without any sense.  For 
 example, the one I quoted at the end of this mail. Does somebody knows 
 why? 

that's base64 encoding... what you quoted does not show the 
content-transfer-encoding line which tells you if it is 

BASE64 or QUOTED-PRINTABLE or 8BIT or 7BIT or BINARY or x-token

i've been dealing with something similar in my recent bouts with the synapse 
mime library and decoding sewly arrived email posts...


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