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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Question for the folks who designed Ada95
Date: 1999/04/28
Message-ID: <wccd80ohhdg.fsf@world.std.com>#1/1
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Sender: bobduff@world.std.com (Robert A Duff)
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Organization: The World Public Access UNIX, Brookline, MA
Newsgroups: comp.lang.ada
Date: 1999-04-28T00:00:00+00:00
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Robert Dewar <robert_dewar@my-dejanews.com> writes:

> There are issues of what types it can be applied to. Shift
> operations applied for example to non-binary modular types
> are quite a puzzle.

And then generic contract problems rear their ugly heads.

> In GNAT, we allow shifts to be applied to any signed or
> binary unsigned integer type whose size is 8, 16, 32, or
> 64 (i.e. natural machine sizes for which shifts make
> sense).

What does GNAT do if it's a generic formal modular type?
I would guess it just checks the rule in the instance.
That's fine for an implementation-defined gizmo, but for
a language-defined feature, we would never want to do that.

- Bob
-- 
Change robert to bob to get my real email address.  Sorry.