Re: [fpc-pascal] Virtual Constants

2013-03-03 Thread Joao Morais 
On Fri, Mar 1, 2013 at 5:31 PM, Daniel Gaspary dgasp...@gmail.com wrote:

 Is possible to have a Class constant with different values in class
 descendants ?

Afaik no, but you can override class virtual methods which might give
you the correct value:

  TA = class
  protected
class function value: integer; virtual; abstract;
  public
class function getvalue: integer;
  end;

  TB = class(TA)
  protected
class function value: integer; override;
  end;

  TC = class(TA)
  protected
class function value: integer; override;
  end;

Joao Morais
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Re: [fpc-pascal] Virtual Constants

2013-03-03 Thread Daniel Gaspary 
On Sun, Mar 3, 2013 at 11:13 AM, Joao Morais jcmorai...@gmail.com wrote:
 Afaik no, but you can override class virtual methods which might give
 you the correct value:

Exactly what I was trying to avoid. :)
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Re: [fpc-pascal] Virtual Constants

2013-03-03 Thread Adrian Veith 

Am 01.03.2013 21:31, schrieb Daniel Gaspary:

The idea is strange. But here it is:

Is possible to have a Class constant with different values in class
descendants ?

Would be something like that:

TA = class
const
 c1: integer; virtual;

 class function GetC1: integer; //returns c1
end;

TB = class(TA)
const
 c1: integer = 1;
end;

TC = class(TA)
const
 c1: integer = 2;
end;
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currently I use a dirty hack to achieve something like this: I have a 
fixed naming scheme for the classname and encode the virtual const in 
the classname.

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[fpc-pascal] Virtual Constants

2013-03-01 Thread Daniel Gaspary 
The idea is strange. But here it is:

Is possible to have a Class constant with different values in class
descendants ?

Would be something like that:

TA = class
const
c1: integer; virtual;

class function GetC1: integer; //returns c1
end;

TB = class(TA)
const
c1: integer = 1;
end;

TC = class(TA)
const
c1: integer = 2;
end;
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Re: [fpc-pascal] Virtual Constants

2013-03-01 Thread Michael Van Canneyt 



On Fri, 1 Mar 2013, Daniel Gaspary wrote:


The idea is strange. But here it is:

Is possible to have a Class constant with different values in class
descendants ?

Would be something like that:

TA = class
const
   c1: integer; virtual;

   class function GetC1: integer; //returns c1
end;

TB = class(TA)
const
   c1: integer = 1;
end;

TC = class(TA)
const
   c1: integer = 2;
end;


Funny coincidence, I was looking for the same thing today :)

Michael.
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