Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!exodus!bendenweyr!flar
From: flar@bendenweyr.Eng.Sun.COM (Jim Graham)
Newsgroups: comp.lang.postscript
Subject: Re: 0 0 1 {} for
Message-ID: <4184@exodus.Eng.Sun.COM>
Date: 8 Dec 90 00:54:29 GMT
References: <7699@hub.ucsb.edu> <371@rusux1.rus.uni-stuttgart.de> <34305@netnews.upenn.edu> <4169@exodus.Eng.Sun.COM>
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Reply-To: flar@bendenweyr.Eng.Sun.COM (Jim Graham)
Organization: Sun Microsystems, Inc.
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From Peter Deutsch:

----- Begin Included Message -----

From: deutsch@parcplace.com (Peter Deutsch)
Subject: 0 0 1 {} for

Please post this for me.  News posting at ParcPlace is broken.

For the record, Ghostscript treats 0 as positive (terminates when the
control variable is greater than the limit).  For those of us who
distinguish "positive" from "strictly positive", there is no ambiguity
about this case.  :-)

		Peter-the-ghost

----- End Included Message -----

My followup to conserve on messages:

Actually, the plot thickens as I discover that the Laserwriter and DPS
both consider "0 0 .1 {} for" an infinite loop, but "0 0 1 {} for" a NULL
statement.  Fancy that.

Reading the description of the exp primitive, it appears that the
redbook considers positive numbers to exclude zero when they use
the term rather than "positive" "non-negative" to mean numbers >= 0.

					...jim