Path: utzoo!utgpu!water!watmath!clyde!att!pacbell!ames!umd5!uflorida!novavax!proxftl!bill
From: bill@proxftl.UUCP (T. William Wells)
Newsgroups: comp.std.c
Subject: Re: enums
Message-ID: <513@proxftl.UUCP>
Date: 21 Jul 88 11:08:21 GMT
References: <1608@dataio.Data-IO.COM> <469@m3.mfci.UUCP>
Reply-To: bill@proxftl.UUCP (T. William Wells)
Organization: Proximity Technology, Ft. Lauderdale
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In article <469@m3.mfci.UUCP> karzes@mfci.UUCP (Tom Karzes) writes:
) While on the subject of enums, here's something that's always bothered me.
) If you define an enum with a long list of values, a natural thing to want
) to do is determine the number of values in the enum (sort of like sizeof).
)
) For example:
)
)     enum tree {
)         oak,
)         elm,
)         maple,
)         birch,
)         willow,
)         cypress,
)         spruce
)     };
)
) Now I'd like to define TREE_COUNT to be the number of trees.  So I have to
) painfully count them, and write:
)
)     #define TREE_COUNT 7
)...
) Does ANSI C provide a reasonable way to do this?

ANSI is irrelevant. Do it like

	enum tree {
		oak, elm, maple, birch, willow, cypress, spruce,
	tree_size};

#define TREE_COUNT ((int)tree_size)

unless you don't need the cast, in which case, just do this:

	enum tree {
		oak, elm, maple, birch, willow, cypress, spruce,
	TREE_COUNT};