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Re: on the order of the const-keyword

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Manfred <noname@add.invalid> writes:

> On 10/29/2021 6:30 PM, David Brown wrote:
>> On 29/10/2021 17:45, Bart wrote:
>>> On 29/10/2021 15:31, David Brown wrote:
>>>> On 29/10/2021 12:30, Bart wrote:
>>>>> On 29/10/2021 09:03, David Brown wrote:
>>>>>> On 28/10/2021 17:50, Meredith Montgomery wrote:
>>>>>>> These seem legal declarations in C:
>>>>>>>
>>>>>>>      const char msg[9] = "warming:";
>>>>>>>      char const msg[9] = "warming:";
>>>>>>>
>>>>>>> What's the difference between them?

[...]

>>> Your advice to read declarations from right to left I think was not
>>> helpful either, being incorrect except in the simplest cases involving
>>> only * modifiers and associated consts.
>>>
>> In other words, it applies fine to the large majority of
>> declarations.  You can add "inside out" to it to cover more cases.  I
>> understand that this is a simplification - but that's what people
>> need at the start.
>
> Not sure about that, at least not this kind of simplification.  I
> think Bart made a good point, in noting that the right-to-left rule
> does not work well in some case, notably with pointers to arrays,
> which is something to be considered at any level of C knowledge.  So,
> as a first a simplification that can be wrong with some declaration
> that, although unfriendly to the novice, can actually be found in real
> code, runs the risk of being more confusing than helpful for the less
> experienced.
>
> The second problem is that when such less experienced happens to read
> the standard's definition (which will happen at some point for any
> serious programmer), they will have the problem that the
> simplification is nowhere near the wording of the standard, so again
> risk of more confusion than help.
>
> From all the answers that have been given here, I think that one of
> James Kuypers' (the one citing the standard's distinction between
> 'declaration-specifiers' and 'init-declarator-list') is the most
> useful, because /that/ is how declarations work in C, plain and
> simple, even if their description is not that simple.

It's really education we're talking about here.  Education is not quite
a scientific area; it's a philosophical one in the Bertrand Russell
sense of philosophy: if there were a clear answer to how to do it, it'd
be called science.  (See the first few pages of his ``A History of
Western Philosophy''.)

Because we don't know what is the right approach, we should more or less
provide them all.  More or less, of course.  And it is a very good idea
to present to students your opinion such as --- this is the right
approach **for sure** and there are other silly approaches too because
some people are too blind to see.

Consider this very thread.  A novice is looking at this and getting a
clear picture of the cloud that education in this area is.  (It's like
that in every area, actually.)  That's (evidently) a fact --- locally at
the very least.

One of the great friends of students is moving-ahead.  You realize
you've got an education when you look back, but to look back you must
move ahead.  So it is a good idea to come up with a modus operandi, even
if it's broken.  This is an important piece of the scientific method:
come up with a hypothesis and stress it until it breaks.

But, of course, if the student can't understand the hypothesis (because
it's too complex), then it might be a useless one.  There are multiple
levels of students --- there are researcher-students, students-students,
children-students.

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Thread

on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-28 12:50 -0300
  Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 17:25 +0100
    Re: on the order of the const-keyword "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2021-10-28 10:10 -0700
      Re: on the order of the const-keyword Guillaume <message@bottle.org> - 2021-10-28 20:40 +0200
      Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:07 -0300
        Re: on the order of the const-keyword James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-10-29 00:48 -0400
    Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 12:56 -0700
      Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 13:18 -0700
        Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 21:35 +0100
          Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 13:57 -0700
            Re: on the order of the const-keyword Thiago Adams <thiago.adams@gmail.com> - 2021-10-28 14:07 -0700
              Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-28 22:54 +0100
              Re: on the order of the const-keyword Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-28 15:37 -0700
                Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-29 00:02 +0100
        Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-28 22:10 +0100
        Re: on the order of the const-keyword Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-10-28 15:13 -0700
        Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:40 -0300
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-28 23:48 -0300
  Re: on the order of the const-keyword James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-10-28 13:04 -0400
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 00:34 -0300
  Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 10:03 +0200
    Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 11:30 +0100
      Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 16:31 +0200
        Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 16:45 +0100
          Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 18:30 +0200
            Re: on the order of the const-keyword Manfred <noname@add.invalid> - 2021-10-30 00:32 +0200
              Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 20:03 -0300
              Re: on the order of the const-keyword Ben Bacarisse <ben.usenet@bsb.me.uk> - 2021-10-30 01:10 +0100
            Re: on the order of the const-keyword Bart <bc@freeuk.com> - 2021-10-29 23:51 +0100
    Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 12:22 -0300
      Re: on the order of the const-keyword David Brown <david.brown@hesbynett.no> - 2021-10-29 18:34 +0200
        Re: on the order of the const-keyword Meredith Montgomery <mmontgomery@levado.to> - 2021-10-29 17:04 -0300

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