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From: adoyle@bbn.com (Allan Doyle)
Newsgroups: comp.lang.ada
Subject: Re: Unusual "use" semantics
Message-ID: <58815@bbn.BBN.COM>
Date: 9 Aug 90 14:51:17 GMT
References: <20@polymnia.tsd.arlut.utexas.edu>
Sender: news@bbn.com
Reply-To: adoyle@vax.bbn.com (Allan Doyle)
Organization: Bolt Beranek and Newman Inc., Cambridge MA
Lines: 35

In article <20@polymnia.tsd.arlut.utexas.edu> fred@polymnia.tsd.arlut.utexas.edu (Fred Hosch) writes:
>My Ada compiler complains about the relation on the fourth line of the
>following
>
>	with TEXT_IO;
>	procedure TEST is
>	begin
>	    if TEXT_IO.COL = 1 then
>	        TEXT_IO.PUT_LINE ("COL is 1");
>	    else
>	        TEXT_IO.PUT_LINE ("COL is not 1");
>	    end if;
>	end TEST;
>
>reporting: no operator visible for positive_count "=" universal integer.
>
>If I add a context clause "use TEXT_IO;" it compiles successfully.
>

The way we have chosen to avoid use and to avoid the ugliness
of TEXT_IO."=" is by using renames:

	function "="(l:text_io.count;r:integer) return boolean
		renames text_io."=";

Sometimes this can get out of hand, with a ton of renames at the top
of packages or procedures but it does make it clear without cluttering
up the logic once you're into the code body.




Allan Doyle                                        adoyle@bbn.com
BBN Systems and Technologies Corporation           (617) 873-3398
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