(Borland?) C++ Language Question

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#2410

From: J.C. Ashworth
Date: Thu, 28 Jan 1993 17:18

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I dunno whether this relates solely to the Borland C++ compiler or whether
it's a general C++ feature / bug?

I seem to be able to do the following quite legally and with the expected
result:

class B
{
// ...
};

class C
{
// ...
};

class D : public B
{
	int xtraField;
// ...
};

B& foo( ... );

D::func( ... )
{
	D& temp = (D&) foo( ... );
	temp.xtraField = 5;
}

Is this OK? How does the cast from B& to D& work? I suppose a cast from B& to C&
would NOT be legal?

thanks.
	
-- 
           ______________    _____________
          /             /\  /            /\        Julian Ashworth
         /_____    ____/ / /   _____    / /        Magdalene College
          \___/   /\ __\/ /   /\___/   / /         Cambridge
             /   / /     /   /_/__/   / /          England
            /   / /     /            / /
  __       /   / /     /   _____    / /            jca17@phx.cam.ac.uk
 /  \_____/   / /     /   /\___/   / /
 \           / /     /   / /  /   / /
  \_________/ /     /___/ /  /___/ /    "It's a great way to steal a car
   \________\/      \___\/   \___\/      but where do we get a jet-pac?"

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Path: arc1-ca.pugleaf.net!sparky!uunet!inmos!fulcrum!bham!warwick!pavo.csi.cam.ac.uk!jca17
From: jca17@phx.cam.ac.uk (J.C. Ashworth)
Subject: (Borland?) C++ Language Question
Message-ID: <1993Jan28.171855.10953@infodev.cam.ac.uk>
Sender: jca17@cl.cam.ac.uk (J.C. Ashworth)
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Organization: U of Cambridge Computer Lab, UK
Date: Thu, 28 Jan 1993 17:18:55 GMT
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