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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Using == operator
Date: Tue, 03 Jan 2017 15:30:43 -0800
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supercat@casperkitty.com writes:
> On Tuesday, January 3, 2017 at 4:06:27 PM UTC-6, Keith Thompson wrote:
>> Even if we assume that that corresponds to `if (apple_count)`, what's
>> the corresponding English for if(node->next)?
>
> Since every pointer which is used in such a context is required to either
> be a valid pointer or a null pointer, the English would be "If the object
> pointed to by 'node' has a valid 'next' pointer, then...."  Although the
> code is in a literal sense comparing a pointer with a null pointer, such
> a comparison is merely the means by which code determines that a pointer is
> valid.

A null pointer is valid in some contexts (including this one), there are
invalid pointers other than the null pointer, and claiming that

    if(node->next)

can be read as

    If the object pointed to by 'node' has a valid 'next' pointer,
    then....

hardly supports the claim that it "reads like English".

-- 
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"