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From: goer@quads.uchicago.edu (Richard L. Goerwitz)
Newsgroups: comp.lang.icon
Subject: Re: alternation surprise
Message-ID: <1991Mar12.235558.1542@midway.uchicago.edu>
Date: 12 Mar 91 23:55:58 GMT
References: <1899@hslrswi.hasler.ascom.ch>
Sender: news@midway.uchicago.edu (News Administrator)
Organization: University of Chicago
Lines: 31

Na@hslrswi.hasler.ascom.ch (Norman H. Azadian) writes:

>I know my postings are starting to sound like an idiot's tour
>of Icon.

If you want a real laugh, try taking a look at icon-group traffic
from, say, three years or so ago (when I was still just learning the
language).  The archives are on cs.arizona.edu (much to my chagrin
:-).

>
>	procedure main()
>	local flag, x
>		flag := 1
>		(\flag)  |  (x := runerr(500))
>		(\flag)  |  x := runerr(500)
>	end
>
>This dies on line 5, which I did not expect.  I guess alternation
>has lower priority than assignment.  Pardon me while I go out and
>stock up on parenthesis.

My golden rule, for a long time , was "conjunction has the lowest prece-
of any infix operation."  Everything else I parenthesized.

You may find that the precedence of alternation makes more sense if you
think of the very common idiom -

    intext :=open(\filename) | &input

-Richard