Newsgroups: comp.lang.c
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: doubles used as booleans
Message-ID: <1989Mar31.172505.25455@utzoo.uucp>
Organization: U of Toronto Zoology
References: <8269@xanth.cs.odu.edu>
Date: Fri, 31 Mar 89 17:25:05 GMT

In article <8269@xanth.cs.odu.edu> kremer@cs.odu.edu (Lloyd Kremer) writes:
>	Can a double be used directly as a boolean?

Any "scalar" type -- an arithmetic or pointer type -- can.

>	The optimizing in the compilers I was using was minimal, and I
>	found that substitutions such as 'if(i)' instead of 'if(i != 0)',
>	and 'if(!n)' in place of 'if(n == 0)' produced smaller code for
>	integral types...

Talk about lazy compilers...

>	[compilers that balk at doing implicit comparison against 0 for double]
>	... Would these compilers be officially broken by today's standards?

Yes.  They've been officially broken by the prevailing de-facto standards
all along, as well.
-- 
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