Newsgroups: comp.os.minix
Path: utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: ARITHMETIC ON ENUMS?
Message-ID: <1990Sep11.015829.22860@zoo.toronto.edu>
Organization: U of Toronto Zoology
References: <30007@nigel.ee.udel.edu>
Date: Tue, 11 Sep 90 01:58:29 GMT

In article <30007@nigel.ee.udel.edu> HBO043%DJUKFA11.BITNET@cunyvm.cuny.edu (Christoph van Wuellen) writes:
>Someone told me that my c68 compiler won't do arithmetic on enums
>(he complains that he cannot add two enums)
>This was made deliberately, I thought enums are symbolic constants, which
>make an ordered type.
>All kinds of comparisons should be fine with enums, but arithmetic?
>
>My K&R books says very little about enums (they came later).

ANSI C says firmly that enums are a kind of integer.  Compilers are
entitled to whine about anything they consider dubious, but they must
not refuse to compile it.

This was a best-compromise minimum-code-breakage solution to a long-standing
debate about the nature of enums.

If you want to compile ANSI C, you need to fix this.  Whether you like
ANSI C or not, it has a far more precise definition and far wider
acceptance than any other flavor of C.
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