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From: "Marin David Condic, 561.796.8997, M/S 731-96" <condicma@PWFL.COM>
Subject: Re: An interesting quote on Java and C++
Date: 1997/09/25
Date: 1997-09-25T00:00:00+00:00	[thread overview]
Message-ID: <97092509394068@psavax.pwfl.com> (raw)


Robert A Duff <bobduff@WORLD.STD.COM> writes:
>Note that modular types are not just about modular arithmetic -- they
>also support bit-wise logical operations.  On a one's complement
>machine, you still want to be able to have all-ones as a bit pattern, if
>you're using these things as bit patterns, even though it's
>arithmetically equal to zero.
>
    This gets me curious about the possibility that we may be spending
    lots of time in the Ada standard dealing with things that are
    non-issues. I ask out of ignorance: Are there any reasonably
    popular microprocessors that are *not* twos-compliment machines? I
    don't think I've ever had occasion to work with a ones-compliment
    microprocessor. If there are some ones-compliment machines out
    there in large numbers, has anyone ever built an Ada compiler for
    them? Would there be any real interest in doing so or are they too
    specialized to expect Ada to suddenly become popular on them?

    It's a little like agonizing over making it convenient to port Ada
    to a DEC-10 processor with a 36bit word. That architecture has
    long since been relegated to history (and I occasionaly miss it!)
    and just about everything in significant use today uses a 16bit,
    32bit or maybe 64bit word. So we can write an Ada standard that
    conveniently maps the standard Integer types to these limits and
    not worry if there's some obscure machine that won't find this
    handy.

    MDC

Marin David Condic, Senior Computer Engineer     ATT:        561.796.8997
Pratt & Whitney GESP, M/S 731-96, P.O.B. 109600  Fax:        561.796.4669
West Palm Beach, FL, 33410-9600                  Internet:   CONDICMA@PWFL.COM
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             reply	other threads:[~1997-09-25  0:00 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1997-09-25  0:00 Marin David Condic, 561.796.8997, M/S 731-96 [this message]
1997-09-25  0:00 ` An interesting quote on Java and C++ Shmuel (Seymour J.) Metz
1997-09-26  0:00   ` Tucker Taft
1997-10-07  0:00   ` Robert I. Eachus
1997-11-19  0:00     ` Shmuel (Seymour J.) Metz
  -- strict thread matches above, loose matches on Subject: below --
1997-10-08  0:00 Marin David Condic, 561.796.8997, M/S 731-96
1997-10-09  0:00 ` Shmuel (Seymour J.) Metz
1997-09-03  0:00 Nasser
     [not found] ` <01bcb881$915526a0$d7000064@sim01.amst.co.at>
1997-09-03  0:00   ` Robert Munck
1997-09-05  0:00     ` Joachim Schroeer
1997-09-06  0:00     ` Robert Dewar
1997-09-24  0:00     ` Shmuel (Seymour J.) Metz
1997-09-08  0:00   ` Robert A Duff
1997-09-09  0:00     ` Robert Munck
1997-09-10  0:00       ` Robert A Duff
1997-09-10  0:00         ` Robert Munck
1997-09-11  0:00           ` Robert Dewar
1997-09-12  0:00             ` Jon S Anthony
1997-09-12  0:00             ` Robert A Duff
1997-09-18  0:00               ` Shmuel (Seymour J.) Metz
1997-09-19  0:00                 ` Robert A Duff
1997-09-20  0:00                   ` Robert Dewar
1997-09-20  0:00                 ` Robert Dewar
1997-09-22  0:00                   ` Robert A Duff
1997-09-20  0:00                 ` Robert Dewar
1997-10-03  0:00                   ` Robert I. Eachus
1997-09-10  0:00         ` Stephen Leake
1997-09-11  0:00           ` Roy Grimm
1997-09-12  0:00             ` Robert A Duff
1997-09-12  0:00         ` Jon S Anthony
1997-09-11  0:00       ` Robert Dewar
1997-09-12  0:00         ` Jon S Anthony
1997-09-12  0:00           ` Robert A Duff
1997-09-03  0:00 ` Samuel Mize
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