[Kde-games-devel] A design issue when using C++

[Ian Wadham]

On Mon, 16 Mar 2009 9:48:21 pm Inge Wallin wrote:
> On Saturday 14 March 2009 11:43:34 Kevin Krammer wrote:
> > class EnemyView
> > {
> >   friend class LevelPlayer;
> >
> > public:
> >   Directiony getDirection( int i, int j )
> >  {
> >     return mLevelPlayer->getEnemyDirectiony( i, j );
> >   }
> >
> > private:
> >   // Level Player is our friend and can thus call the private constructor
> >   // Nobody else can create instances of the view
> >   EnemyView( LevelPlayer *levelPlayer ) : mLevelPlayer( levelPlayer ) {}
> >
> >   LevelPlayer *mLevelPlayer;
> > };
> > <snip>
>
> Isn't this the classic Facade design pattern?  We have something similar in
> Marble where we have a read-only facade to the main marble data store
> called MarbleDataFacade.  I suggest you name your class not ...View, but
> ...Facade instead.
>
With respect, to both Kevin and Inge, I would not use either name.  That
is because I think names in programs should be descriptive of *what*
something is or does, rather than how it is implemented.  If there is
some aspect of the implementation that needs to be recorded, such
as use of the Facade pattern, I would mention it in the API doco or
program comments.

> (You can of course take a look at Marble to see the details there.)
>
I did, and could not help thinking why not call it MarbleDataReadOnly
or some such?  What if you later find a need for another facade, yielding
a different subset of or mode-of-access to the Marble data?  What will
you call the new facade?

All the best and thanks again for your help, Ian W.