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From: gv9b2c9z@umiami.ir.miami.edu (Ordinary Man)
Newsgroups: comp.sys.mac.programmer
Subject: Double dereferenced handles
Message-ID: <1991Jan30.215459.7730@umiami.ir.miami.edu>
Date: 31 Jan 91 02:54:59 GMT
Organization: Univ of Miami IR
Lines: 48

Is it bad programming practice to double dereference a handle to a record
(with linked lists in mind)? Is there a better way to do it without 
sacrificing a lot of time spent implementing it? I've tried linked lists
both ways (with all pointers and with all handles). Right now I'm 
implementing it with all handles. I don't notice any speed difference that's
significant so is it better to derefernce the handle twice or to set it
to a pointer and then use that pointer? Let me illustrate:

type
	listHand=^listPtr;
	listPtr=^list;
	list=record 
		item:whatever;
		next:listHand;
	end;

var theList:listHand;
    temp:listPtr;

Do I say this:

	HLock(Handle(theList));
	temp:=theList^;
	temp^.item:=whatever;
	...

or this:

	HLock(Handle(theList));
	theList^^.item:=whatever;
	...

Or does it matter?


Thanks in advance,

		==Dan

-- 
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