When is a cast not a cast?

[Peter da Silva]

Think of memory as a deck of cards. You can add 3 to the 5 of spades, and
get the 8 of spades. You can subtract the 4 of clubs from the 9 of clubs
and get 5 cards difference. But you can't add the 3 of hearts to the four
of hearts. -- you can't add pointers to pointers.

Continuing, you can't subtract the three of hearts from the four of spades.
-- you can't compare pointers of different types.
-- 
Peter da Silva, Xenix Support, Ferranti International Controls Corporation.

Business: uunet.uu.net!ficc!peter, peter at ficc.uu.net, +1 713 274 5180.
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