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digitalmars.D.bugs - [Issue 7726] New: 'virtual' keyword please

reply d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7726

           Summary: 'virtual' keyword please
           Product: D
           Version: D2
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: critical
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: turkeyman gmail.com



Used in conjunction with 'final:' at the top of the class, gives access to
explicit virtual code.
Allow implementation of such a policy for a large code team.

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Mar 18 2012
next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7726


Walter Bright <bugzilla digitalmars.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bugzilla digitalmars.com
           Severity|critical                    |enhancement


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Mar 18 2012
prev sibling next sibling parent d-bugmail puremagic.com writes:
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Piotr Szturmaj <pszturmaj tlen.pl> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pszturmaj tlen.pl



---
Instead, please use final: at the bottom of the class.

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Mar 18 2012
prev sibling next sibling parent d-bugmail puremagic.com writes:
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Then I can't use private:, since that suffers from the same problem of not
having a corresponding 'public'.

{
  [public virtual methods]

private:
  [data members]

final:
  [non-virtual methods] // are now private
}


{
  [public virtual methods]

final:
  [non-virtual methods]

private:
  [data members] // error because of the 'final:' bug
}



This all leads to messy, and rather difficult to follow classes. I like to keep
associated stuff together.
I also really like the virtual keyword, it states in the API clearly how to
extend the class, and you can grep for it.

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Mar 19 2012
prev sibling next sibling parent d-bugmail puremagic.com writes:
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---
You can tag individual members with public/private and final. final: and final
{ } are just for convenience.

You can also try something like this:

{
    void virtualMethod() {}

private:
    int privateMember;

public final:
    void finalMethod() { } // public
}

I guess you are opting for virtual: keyword to just disable existing final:
specifier. There are other possible solutions without adding a new keyword:

- Use default: to restore public and virtual.
- Use negation, like !final: to disable specifiers that differ from public and
virtual.

But I'm ok with current approach.

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prev sibling next sibling parent d-bugmail puremagic.com writes:
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No actually, I want a 'virtual' keyword to write in front of virtual methods.
Not 'virtual:', I don't believe that would be very useful.


every programmer that exists expects:

class MyClass
{
final:
this()
  void method();

   property void thing(int t) {}
   property int thing() {}


}

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Mar 19 2012
prev sibling next sibling parent d-bugmail puremagic.com writes:
http://d.puremagic.com/issues/show_bug.cgi?id=7726




*crap, I tapped tab and the 'commit' button gained focus, and when I pressed
space bar, it posted.*

class MyClass
{
final:
  this();

   property void property1(int t)
   property int property1()

   property void thing(int t)
   property int thing()
  void doThing()

  void addUnrelated(Unrelated x);
  Unrelated getUnrelated();
  virtual void updateUnrelateds();

  // etc. 

private:
  virtual void update();
  virtual void draw();

  void handlerDelegate();
  void handlerDelegate2();

  int data1;
  float data2;
  ...
}

Ie. logically group stuff, mark the occasional virtual explicitly, continue as
final.

This looks like a fairly realistic class to me. I really want to be able to
explicitly mark each function that is virtual in this way.

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prev sibling next sibling parent d-bugmail puremagic.com writes:
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---
You can write it like this:

class MyClass
{
final {
  this();

   property void property1(int t)
   property int property1()

   property void thing(int t)
   property int thing()
  void doThing()

  void addUnrelated(Unrelated x);
  Unrelated getUnrelated();
}
  void updateUnrelateds();

  // etc. 

private:
  void update();
  void draw();

final {
  void handlerDelegate();
  void handlerDelegate2();
}

  int data1;
  float data2;
  ...
}

IMHO it makes no sense to introduce virtual keyword since virtual in D is the
default...

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Mar 19 2012
prev sibling next sibling parent d-bugmail puremagic.com writes:
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Yeah, I'll do that in the mean time, but it's not a 'solution'.

I still can't grep for virtual (important). And it's really ugly; breaks
indentation policy, separates things in and out of braces.
D is meant to be cleaner and tidier than C++. Certainly not messier.

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Mar 19 2012
prev sibling parent d-bugmail puremagic.com writes:
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timon.gehr gmx.ch changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |timon.gehr gmx.ch






 every programmer that exists expects:
 


I'd be careful with strong/wrong statements of this kind. They make your
argument seem feeble even if it is not.

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Mar 21 2012