Re: Results of survey re. a new array size operator

On 2025-01-30, Scott Lurndal <scott@slp53.sl.home> wrote:

The decades old standard idiom of sizeof(x)/sizeof(x[0])
is self-documenting and requires no macros or new language
features.

I've seen the bug more than once whereby x was a pointer.

That's a threat whether you use a macro or open-code it,
of course.

GCC has developed a diagnostic for this; so whether you have
a macro or write it out as above, you care covered.

If a standard-defined operator or macro were available for this, it
could require a diagnostic in every conforming implementation,
when the argument isn't an array. Implementations that don't
have a diagnostic for sizeof(ptr)/sizeof(ptr[0]) would still
have to diagnose countof(ptr), or whatever it is called.

That would be a benefit in addition to saving keystrokes.

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