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devel / comp.lang.c / Re: I think references should have been const by default

Re: I think references should have been const by default

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https://www.novabbs.com/devel/article-flat.php?id=18737&group=comp.lang.c#18737

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From: jameskuy...@alumni.caltech.edu (James Kuyper)
Newsgroups: comp.lang.c
Subject: Re: I think references should have been const by default
Date: Mon, 25 Oct 2021 10:28:34 -0400
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by: James Kuyper - Mon, 25 Oct 2021 14:28 UTC

On 10/25/21 4:21 AM, RacingRabbit@watershipdown.co.uk wrote:
....
> Consts in C are pointless because it doesn't have references and its rather
> difficult to "accidentaly" dereference a pointer to update the value its
> pointing to.

Actually, it isn't. All it takes is unfamiliarity with the functions
you're using. I remember, in particular, I've seen messages from several
people expressing surprise that strtok() writes to the string that you
pass it as it's first argument. If the pointers they had tried to pass
to strtok() had been const char * rather than char*, they would have
been reminded of the problem. Of course, they might not have understood
the reminder, if they weren't familiar with functions whose declarations
use "const" appropriately. All of the standard library functions do so,
many other libraries don't.

However, that's only a part of the problem that "const" is intended to
help avoid. The other part is intentionally dereferencing a pointer to
update the value it's pointing act, due to being unaware of the fact
that what it's pointing at is something that shouldn't be written to. In
code which doesn't make proper use of "const", that's a fairly common
mistake, at least in my experience (which is admittedly limited, since
my own code does make proper use of "const").

Subject	Author
Re: I think references should have been const by default	James Kuyper