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From: Chet Ramey <chet.ramey@case.edu>
Newsgroups: gnu.bash.bug
Subject: Re: Inconsistent arithmetic evaluation of parameters
Date: Wed, 2 Sep 2015 11:24:42 -0400
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On 9/2/15 11:19 AM, Greg Wooledge wrote:
> On Wed, Sep 02, 2015 at 10:16:14AM -0500, Dennis Williamson wrote:
>> The $ is implied.
> 
> That is completely absurd.  (And wrong.)

Not exactly.  When the arithmetic evaluator encounters a token that is of
the form of a shell identifier (`bar'), in a context where an operand is
needed, it treats it as a shell variable and looks up the variable's
value.  In that sense, it's an expansion.

The difference between bash and dash is what each shell does with that
value.

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
		 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/