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From: jimbo@tandem.com (Jim Lyon)
Newsgroups: comp.lang.c
Subject: Re: What's an LValue [was A quick question]
Message-ID: <1991Mar13.050555.26149@tandem.com>
Date: 13 Mar 91 05:05:55 GMT
References: <1991Mar12.030759.26698@nntp-server.caltech.edu> <31306@shamash.cdc.com>
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In article <31306@shamash.cdc.com> bls@u02.svl.cdc.com (Brian Scearce) writes:
>The rules are pretty easy (especially if you have your copy of
>Harbison and Steele on your desk :-)
>
>0. variable names (excepting function, array and enum constant
>   names) are lvalues.
>1. e[k] is an lvalue, regardless of whether e and k are lvalues.
>2. (e) is an lvalue iff e is.
>3. e.name is an lvalue iff e is.
>4. e->name is an lvalue regardless of whether e is an lvalue.
>5. *e is an lvalue regardless of whether e is an lvalue.

Rules (1) and (5) need to be further qualified.  e[k] and *e are
lvalues regardless of whether e and k are lvalues, UNLESS the type
of e[k] or *e is either Array... or Function...

For example, if A is declared as "int A[10][10]", then "A[5]"
is not an lvalue, because the type of "A[5]" is "Array of int".

-- Jim Lyon
   jimbo@Tandem.Com