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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: "subexpression"
Date: Fri, 27 Nov 2015 19:42:35 -0800
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James Kuyper <jameskuyper@verizon.net> writes:
[...]
> A sub-expression of an expression is either one of it's own direct
> operands, or recursively, one of it's operand's sub-expressions.

Is an expression a subexpression of itself?  If so, we could refer to a
"proper subexpression" much as we talk about "proper subsets".

The standard's usage of the term is consistent with an expression *not*
being its own subexpression.

> I don't claim that definition to be authoritative, but I think it
> expresses correctly my understanding of the term, and I don't think it
> conflicts with anything the standard says about sub-expressions.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"