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From: progers@acm.org
Subject: Re: Math on dimensioned quantities
Date: 1996/07/10
Message-ID: <4s0g7q$dca@uuneo.neosoft.com>#1/1
X-Deja-AN: 167587558
references: <9607091345.AA03915@most> <DuB08H.2HI@world.std.com>
organization: NeoSoft, Inc.  
reply-to: progers@acm.org
newsgroups: comp.lang.ada
Date: 1996-07-10T00:00:00+00:00
List-Id: <comp.lang.ada>


In <DuB08H.2HI@world.std.com>, bobduff@world.std.com (Robert A Duff) writes:
>In article <9607091345.AA03915@most>,
>W. Wesley Groleau (Wes) <wwgrol@PSESERV3.FW.HAC.COM> wrote:
>>writers listening?--how about a pragma similar to
>>
>>   pragma Disallow ( Operation => "*", For_Type => Inch );
>
>How about:
>
>    function "*"(X, Y: Inches) return Inches is <>;
>
>?  Then this particular "*" is abstract and therefore can't be called,
>and this is checked at compile time.  You can still multiply
>inches*inches to get square-inches.  It's annoying that you might have
>to declare lots of "is <>" functions, but I think it does solve the
>problem.

Bob's memory is too good :) The "<>" syntax was changed to use the 
reserved word "abstract".


pat
---------------
Patrick Rogers
progers@acm.org