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Re: technology discussion → does the world need a "new" C ?

From Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups comp.lang.c
Subject Re: technology discussion → does the world need a "new" C ?
Date 2024-08-15 01:43 -0700
Organization A noiseless patient Spider
Message-ID <86a5hep45h.fsf@linuxsc.com> (permalink)
References (16 earlier) <86o7717jj1.fsf@linuxsc.com> <v6ti10$3gru4$1@dont-email.me> <v78af7$1qkuf$1@dont-email.me> <20240717163457.000067bb@yahoo.com> <v78piu$1su4u$1@dont-email.me>

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Bart <bc@freeuk.com> writes:

[on comparing array arguments in C with call-by-reference]

> [...] the differences [between C rules and true call-by-reference]
> can be summarised here;  [...]
>
>                                  Call     Array access in callee
>
>     C call-by-value              F(A)     A[i]
>
>     true call-by-reference       H(A)     A[i]
>
> What the user has to write is what's important, and here it is clear
> that they write the same thing [in the two cases shown].


The comparison above is misleading because it is incomplete.
Let's compare the two modes more fully:


                        C call-by-value         call-by-reference
                        ===============         =================
  at call:

    (array argument)    F(A)                    H(A)

    (pointer argument)  F(p)                    (disallowed)

    (null argument)     F(0)                    (disallowed)


  inside function:

    (access)            A[i]                    A[i]

    (update)            A[i] = ...              A[i] = ...

    sizeof A            (pointer size)          (array size)

    A++                 (changes A variable)    (disallowed)

    A = (new value)     (changes A variable)    (disallowed)


The more complete comparion illustrate why C semantics should not
be thought of as call-by-reference.

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Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-12 13:12 +0200
  Re: technology discussion → does the world need a "new" C ? bart <bc@freeuk.com> - 2024-07-12 12:21 +0100
    Re: technology discussion → does the world need a "new" C ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-07-12 12:14 +0000
      Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-07-12 09:54 -0700
        Re: technology discussion ? does the world need a "new" C ? dave_thompson_2@comcast.net - 2024-08-25 17:16 -0400
    Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-12 15:22 +0200
    Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-07-12 08:58 -0700
      Re: technology discussion → does the world need a "new" C ? bart <bc@freeuk.com> - 2024-07-12 19:33 +0100
        Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-07-12 13:38 -0700
        Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-07-17 16:42 -0700
  Re: technology discussion → does the world need a "new" C ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-07-12 11:52 +0000
    Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-07-12 15:35 +0300
  Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-07-12 15:42 +0300
    Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-12 15:07 +0200
      Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-07-12 16:31 +0300
        Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-13 04:49 +0200
    Re: technology discussion → does the world need a "new" C ? bart <bc@freeuk.com> - 2024-07-12 15:44 +0100
      Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-13 12:13 +0200
    Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-07-13 02:01 -0700
      Re: technology discussion → does the world need a "new" C ? BGB <cr88192@gmail.com> - 2024-07-13 04:39 -0500
        Re: technology discussion → does the world need a "new" C ? Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-07-13 12:35 +0200
        Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-07-13 14:43 -0700
        Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-07-17 12:38 +0100
          Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-07-17 16:34 +0300
            Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-07-17 16:56 +0100
              Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-15 01:43 -0700
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-15 13:48 +0100
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-15 15:33 +0100
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-15 17:08 +0100
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-16 01:08 +0100
                Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-08-16 12:10 +0300
                Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-08-16 02:18 -0700
                Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-08-16 12:38 +0300
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-16 12:28 +0100
                Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-08-16 11:40 -0700
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-16 11:17 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-16 11:42 +0200
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-16 11:00 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-16 16:31 +0200
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-19 00:54 +0100
                Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-18 18:03 -0700
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-19 09:26 +0200
                Re: technology discussion → does the world need a "new" C ? Michael S <already5chosen@yahoo.com> - 2024-08-19 12:22 +0300
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-19 14:14 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-19 21:18 +0200
                Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-08-16 10:56 -0700
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-17 12:26 +0200
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-17 11:38 +0100
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-16 15:19 +0100
                Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-17 07:41 -0700
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-17 18:07 +0100
                Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-17 18:22 -0700
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-18 12:35 +0100
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-19 01:01 +0100
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-19 01:57 +0100
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-19 02:30 +0100
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-19 12:29 +0100
                Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-08-20 00:33 +0100
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-20 12:42 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-16 10:04 +0200
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-16 12:45 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-08-16 16:51 +0200
                Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-08-15 14:36 -0700
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-15 23:22 +0100
                Re: technology discussion → does the world need a "new" C ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-08-15 23:29 +0000
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-16 01:46 +0100
                Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-08-15 18:21 -0700
                Re: technology discussion → does the world need a "new" C ? tTh <tth@none.invalid> - 2024-08-16 03:37 +0200
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-08-16 12:14 +0100
                Re: technology discussion → does the world need a "new" C ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-08-15 14:52 -0700
          Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-07-17 19:07 +0200
          Re: technology discussion → does the world need a "new" C ? BGB <cr88192@gmail.com> - 2024-07-17 12:53 -0500
            Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-07-18 09:46 +0200
              Re: technology discussion → does the world need a "new" C ? BGB <cr88192@gmail.com> - 2024-07-18 05:05 -0500
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-07-18 14:41 +0200
                Re: technology discussion → does the world need a "new" C ? Bart <bc@freeuk.com> - 2024-07-18 14:00 +0100
                Re: technology discussion → does the world need a "new" C ? David Brown <david.brown@hesbynett.no> - 2024-07-18 18:01 +0200
                Re: technology discussion → does the world need a "new" C ? BGB <cr88192@gmail.com> - 2024-07-18 14:25 -0500
                Re: technology discussion → does the world need a "new" C ? vallor <vallor@cultnix.org> - 2024-07-18 22:23 +0000
                Re: technology discussion → does the world need a "new" C ? BGB <cr88192@gmail.com> - 2024-07-18 12:40 -0500
      Re: technology discussion → does the world need a "new" C ? Ben Bacarisse <ben@bsb.me.uk> - 2024-07-13 13:35 +0100
        Re: technology discussion → does the world need a "new" C ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-07-17 01:09 -0700

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