[omniORB] idl and structs

[Mike Olson]

David Hyde wrote:
> 
> I've just noticed, to my horror, that IDL structs cannot inherit from each
> other (I'm busy converting an interface from a proprietary language where
> complex structures have been built up using inheritance).  Is there a
> specific reason for this?  Has anyone fudged their way around this?

I've gotten around this before with Unions

enum TYPE {
  A_TYPE,
  B_TYPE
};

struct A {
  attribute foo;
};

struct B {
  attribute bar;
};

union CommonUnion switch(TYPE) {
  case A_TYPE: A athing;
  case B_TYPE: B bthing;
};

struct Common {
  CommonUnion commonData;
  attribute otherData;
};



Its not as easy to work with as inheritence, but it gets across the same
data.  Also, because I mostly use Python as a client, I change what is
instantiated on the client side so that it is a proper inheritence tree.

Mike

> 
> Thanks
> 
> David
> 
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-- 
Mike Olson				 Principal Consultant
mike.olson@fourthought.com               (303)583-9900 x 102
Fourthought, Inc.                         http://Fourthought.com 
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