From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: overriding "*", was Re: What's the ICFP Programming contest?
Date: Wed, 2 Jul 2003 13:13:41 -0500
Date: 2003-07-02T13:13:41-05:00 [thread overview]
Message-ID: <vg68424gi7qjd2@corp.supernews.com> (raw)
In-Reply-To: 9mEMa.19277$926.1303@sccrnsc03
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.
next prev parent reply other threads:[~2003-07-02 18:13 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-06-26 1:30 What's the ICFP Programming contest? tmoran
2003-06-26 8:24 ` Preben Randhol
2003-06-27 20:37 ` Michael Erdmann
2003-06-28 0:21 ` tmoran
2003-06-28 7:33 ` Michael Erdmann
2003-06-29 6:47 ` Hyman Rosen
2003-06-29 22:37 ` tmoran
2003-07-01 5:58 ` overriding "*", was " tmoran
2003-07-01 20:52 ` Randy Brukardt
2003-07-02 17:10 ` tmoran
2003-07-02 18:13 ` Randy Brukardt [this message]
2003-07-03 7:55 ` Robert I. Eachus
2003-07-04 7:01 ` Robert I. Eachus
replies disabled
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox