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

Kaz Kylheku <643-408-1753@kylheku.com> writes:

On 2024-07-07, James Kuyper <jameskuyper@alumni.caltech.edu> wrote:
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On 7/7/24 16:10, BGB wrote:
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On 7/7/2024 9:03 AM, James Kuyper wrote:
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On 7/7/24 00:55, BGB wrote:
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On 7/6/2024 5:38 PM, Keith Thompson wrote:

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No, there is no implicitly defined pointer.

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This implicit pointer need not exist at a location in memory...

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Which is why C doesn't give you access to it's location in memory -
something you complained about earlier.

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I don't think I was claiming that one should have direct access to its
location or value within the language, rather that their existence and
behaviors could be acknowledged in the language design (for a "not
quite C" language).

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I think that the existence of an implicit pointer would be a bad thing
to acknowledge, given that the language doesn't require that it exist,
and typical implementations don't use them.  From what I understand, the
fact that your implementation does have implicit pointers makes it a rarity.

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Ritchie's B language had arrays which contained a pointer to their
first element.  Via a hack, it was possible to relocate an array.
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In C, such a thing is not simply not required;  it is ruled out
by the detailed semantic description of arrays.  [...]

Not to muddy the waters, but there are circumstances where
it is advantageous to put an array "somewhere else" and
simply keep a pointer to it locally.

Having said that, it must also be said that such pointers
are purely implementation details and have no place in
the abstract machine.  As far as the abstract machine is
concerned, an array is just an array, and not an array
and a pointer.