From owner-freebsd-hackers@FreeBSD.ORG  Mon Apr 25 17:56:40 2005
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Date: Mon, 25 Apr 2005 19:56:35 +0200
From: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
To: Ron Chen <ron_chen_123@yahoo.com>
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Subject: Re: C-style expression processing...
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On Sun, Apr 24, 2005 at 10:50:16PM -0700, Ron Chen wrote:
> Hi,
> 
> I am trying to add a new feature in Gridengine
> (free/opensource) to support ex-LSF users - there are
> more and more LSF users migrating to Gridengine), and
> some requested this one:
> 
> In LSF, a user can specify from the command line the
> resource requirements of a batch job:
> 
>  (mem >= 100 || pg < 200.0)
> 
> Where mem and pg are variables (they changes in time,
> and the master cluster scheduler has the most
> up-to-date information). And what I need is to find
> out whether the expression is true or not.
> 
> My question is, is there an expression processing
> library that can handle complex equations easily?

you can easily parse it, using yacc/lex... and even hand-writing such parser
cannot be difficult..