Path: utzoo!mnetor!uunet!husc6!cmcl2!brl-adm!umd5!purdue!gatech!udel!princeton!mccc!pjh
From: pjh@mccc.UUCP (Peter J. Holsberg)
Newsgroups: comp.lang.c
Subject: Re: Associativity -- what is it?
Message-ID: <234@mccc.UUCP>
Date: 22 Feb 88 18:55:39 GMT
References: <226@mccc.UUCP> <224@sdrc.UUCP>
Reply-To: pjh@mccc.UUCP (Peter J. Holsberg)
Organization: The College on the Other Side of US Route 1
Lines: 32

In article <224@sdrc.UUCP> scjones@sdrc.UUCP (Larry Jones) writes:
|In article <226@mccc.UUCP>, pjh@mccc.UUCP (Peter J. Holsberg) writes:
|> 
|> I find that associativity is a *very* difficult thing for me to explain,
|> undoubtedly because I don't understand it!  Would someone come to my
|> rescue?  Here's an example (assume that everything's been declared
|> correctly):
|> 
|> 	x = 3 * i ++;
|> 
|> Book says that ++ has a higher precedence than *, and that ++
|> associates from R->L.  That makes me think that ++ should be applied
|> first, but I know it isn't.  But ????
|
|But ++ IS applied first!  The key point here is that the RESULT of postfix
                                                          ^^^^^^^^^^^^^^^^^
|++ is the value BEFORE incrementation, not that postfix ++ is somehow deferred
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|until later.

Well, that still leaves me confused.  If i has the value 7, it is 7 that
is added to 3, so it seems to be that the ++ *is* deferred until later. 
Also, ++ has higher precedence than +, so why is the incrementation
delayed until after the current value of i is used?
 
I think we're getting close, though.  :-)  Thanks for the help.

-- 
Peter Holsberg                  UUCP: {rutgers!}princeton!mccc!pjh
Technology Division             CompuServe: 70240,334
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