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From: Lawson.English@p88.f15.n300.z1.fidonet.org (Lawson English)
Newsgroups: comp.sys.mac.programmer
Subject: early and late binding in THINK C
Message-ID: <4300.27D4F05E@stjhmc.fidonet.org>
Date: 5 Mar 91 16:43:40 GMT
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Chris Wright writes in a message to All

you cast myToBeCast : (MySubClass *) myToBeCast -> uniqueToSubFn() 
CW>  then all is sweetness and light.  How come the compiler is smart 
CW> enough to allow runtime (or dynamic) 
CW>  binding to the subclasses methods, but not smart enough to know 
CW> that myToBeCast is now a member  of the subclass?????? 

Because it's not very smart? Seriously, do you know of any compiler that keeps
track of type-casting? IE, if you do a "(char*) myInt", do you expect the compiler
to remember that myInt was just used as (*char)?

If not (and I'd love to see the headaches that THAT would cause if you found
a compiler that would actually do it), why do you expect a compiler to remember
the typecast for an object? I suppose that it could be built-in, simply for
objects, but that sounds like pretty un-documentable behavior to me...


Lawson
 

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