Message-ID: <559599C2.6090505@suse.cz>
Date: Thu, 02 Jul 2015 22:06:26 +0200
From: Michal Marek <mmarek@suse.cz>
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To: Martin Walch <walch.martin@web.de>
CC: Jan Beulich <JBeulich@suse.com>, pebolle@tiscali.nl,
        linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] kconfig: allow use of relations other than (in)equality
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Dne 2.7.2015 v 15:04 Martin Walch napsal(a):
> Hi,
> 
>> 1: allow use of relations other than (in)equality
> 
> I know it is a bit late for objections. Still, I want to point out that
> this looks to me like a major extension to the language.
> 
> Kconfig is a configuration language, and as far as I can tell it is
> (intentionally) not Turing complete to keep the configuration simple and
> controllable. All relations that have been defined so far check for equality
> (or for being not equal). The new relations "<=", ">=", "<", and ">" add more
> expressiveness, potentially making the language actually more complex and
> reasoning harder.

The patch just adds four new binary operations of the same order as the
existing == and !=, with a the semantics that everybody expects. And the
grammar for kconfig expressions is so simplistic that you cannot even
write things like (A && B) == (C && D). So turing completeness is not a
topic here, neither before nor after this patch.

Michal
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