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digitalmars.D - Reimplementing interface

reply "Frank Benoit (keinfarbton)" <benoit tionex.removethispart.de> writes:
Bug http://d.puremagic.com/issues/show_bug.cgi?id=502
points out: a class that reimplements an interface, needs also to
reimplement all methods from the interface.

Currently this means, it is really necessary to do

  int f( int i ){
    return super.f( i );
  }

I think an alias should do the job.

  alias SuperClass.f f;

comments?
Nov 26 2006
parent Stewart Gordon <smjg_1998 yahoo.com> writes:
Frank Benoit (keinfarbton) wrote:

 Bug http://d.puremagic.com/issues/show_bug.cgi?id=502
 points out: a class that reimplements an interface, needs also to
 reimplement all methods from the interface.
 
 Currently this means, it is really necessary to do
 
   int f( int i ){
     return super.f( i );
   }
 
 I think an alias should do the job.
 
   alias SuperClass.f f;
 
 comments?


I agree.  And I've disputed the excuse for labelling that bug as invalid 
on this basis.

I think the reason for requiring interfaces to be explicitly implemented 
in that very class is that, if you don't watch out, you may end up 
implementing the interface by an inherited method with very different 
semantics.  But if you declare it as an alias in the class that 
implements the interface, then you're showing that you have watched out. 
  And so this should be one way of implementing the interface.

I don't really know what practical uses there are for reimplementing the 
same interface in a derived class, but in any case the same argument for 
allowing this applies.

Stewart.

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Nov 26 2006