ext/standard: Add is_assoc_array() to detect associative arrays

[arshidkv12]

Introduce a new core function is_assoc_array() that determines whether
an array is associative based on internal storage. The implementation
uses HT_IS_PACKED for fast O(1) detection.

Packed arrays are treated as non-associative, while hash-based arrays
are considered associative.

[devnexen]

That looks very much RFC material to me

[arshidkv12]

https://wiki.php.net/rfc/is_assoc_array
https://externals.io/message/130115

[devnexen]

just my personal take on this. Not sure how useful it really is, e.g. array_is_list()

[devnexen]

nevermind, Bob already mentioned it :)

[arshidkv12]

Thank you

[devnexen]

try to take note from the discussion, if you want to do a proposal next time

The fact that this RFC doesn't even mention PHP's already available native
function (array_is_list() - which performs the inverse) indicates that this
initiative is under-researched.

Cheers.

[arshidkv12]

What is your opinion on https://wiki.php.net/rfc/array_only_except?

[devnexen]

it is a better selling point, you can live without still tough. Reading the discussion, some people already mention array_intersect_key and array_diff_key. Not sure that is good enough to be added in standard but I do not represent php all myself maybe other people have different opinions :)