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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: overriding "*", was Re: What's the ICFP Programming contest?
Date: Wed, 2 Jul 2003 13:13:41 -0500
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Date: 2003-07-02T13:13:41-05:00
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tmoran@acm.org wrote in message <9mEMa.19277$926.1303@sccrnsc03>...
>>That's a well-known feature of Ada 95 (and it is incompatible with Ada
>>83). The problem is that you can't hide the mixed fixed point multiply
>>(any fixed * any fixed -> universal fixed), so it is ambiguous
anywhere
>>other than in the children of your fixed point package.
>  Why did it work in Ada 83, and why was it changed?

Ada 83 required that the mixed fixed point operators be used in a type
conversion:

     A := My_Fixed(B*C);

But this didn't allow literals, and was clumsy. So, it was changed to
take the type from context:

    A := B*C;

But that makes the operators always visible, so they get priority over
use-visible ones. The incompatibility that that causes was thought to
not be too important; but we know better now.

              Randy.