Path: utzoo!utgpu!news-server.csri.toronto.edu!torsqnt!lethe!druid!darcy
From: darcy@druid.uucp (D'Arcy J.M. Cain)
Newsgroups: comp.lang.c
Subject: Re: Assignment in test: OK?
Message-ID: <1990Sep14.141925.18163@druid.uucp>
Date: 14 Sep 90 14:19:25 GMT
References: <BURLEY.90Sep6024459@world.std.com> <928@hls0.hls.oz> <18326@ultima.socs.uts.edu.au>
Organization: D'Arcy Cain Consulting, West Hill, Ontario
Lines: 29

In article <18326@ultima.socs.uts.edu.au> jeremy@sinope.socs.uts.edu.au (Jeremy Fitzhardinge) writes:
>this is quite a useful construct.  How many would prefer
>	if (thing != NULL)
>	{
>		fp = fopen(thing, "r");
>		if (fp == NULL)
>			barf();
>	}
>to
>	if (thing && (fp = fopen(thing, "r"))
>		barf();
>?
I think I prefer the former since the second version has a bug.  I think you
meant to say:
    if (thing && ((fp = fopen(thing, "r")) == NULL)
and just as a matter of style I would use:
    if ((thing != NULL) && ((fp = fopen(thing, "r")) == NULL)

And that solves the =/== problem as well.

I suppose you may also have meant
    if ((thing == NULL) || ((fp = fopen(thing, "r")) == NULL)
unless the 'file not named' error is handled elsewhere.

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D'Arcy J.M. Cain (darcy@druid)     |
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