Path: utzoo!attcan!uunet!husc6!bbn!uwmcsd1!ig!agate!ucbvax!pasteur!ic.Berkeley.EDU!faustus
From: faustus@ic.Berkeley.EDU (Wayne A. Christopher)
Newsgroups: comp.lang.misc
Subject: Re: Modern languages (Slight return)
Message-ID: <3631@pasteur.Berkeley.Edu>
Date: 24 May 88 22:03:54 GMT
References: <2031@uoregon.uoregon.edu> <3292@enea.se> <2414@uvacs.CS.VIRGINIA.EDU> <2096@ur-tut.UUCP>
Sender: news@pasteur.Berkeley.Edu
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In article <2031@uoregon.uoregon.edu>, markv@uoregon.uoregon.edu (Mark VandeWettering) writes:
> 	Uses of the cpp should be:
> 	3.	Hide awkward dereferencing of nested pointer structures,
> 		esp complicated unions....

Another use that's related to this is replacing things like

	for (ptr = stuff->things; ptr != NULL; ptr = ptr->next)

with

	foreach_thing(stuff, ptr)

This has the advantage of hiding the representation of the set, so that
if you change it to a hash table or an array you needn't change all your
code.  I think it's pretty obvious what it does, even though it does
modify the syntax.

Of course, it goes without saying that

#define WHILE(s) while (s) {
#define ELIHW }

is an evil thing...

	Wayne