Re: [RFC] Add is_list(mixed $value): bool to check for list-like arrays

On Wed, Jan 6, 2021 at 1:46 AM tyson andre <tysonandre775@hotmail.com> wrote: > Hi internals, > > > > > I probably brought this up in a previous thread, but I think it's > worth > > > > considering again here, given recent changes to the RFC: > > > > > > > > I think it would make more sense to introduce this as `function > > > > array_is_list(array $array): bool`. That is, a function that only > accepts > > > > arrays in the first place and determines whether the given array is > a list. > > > > > > > > Your RFC does mention this possibility, but I think the argument it > makes > > > > against it is not particularly strong, especially given the recent > rename. > > > > The argument is that is_array_and_list($array) is shorter than > writing out > > > > is_array($array) && array_is_list($array) -- that's still true, but > with > > > > the new name, it's really not that much shorter anymore. > > > > > > > > On the other hand, is_array($array) && array_is_list($array) cleanly > > > > separates out the two predicates. If we take into account the fact > that in > > > > the vast majority of cases we will know a-priori that the input is an > > > > array, just not whether it is a list, making the function > > > > array_is_list($array) is both clearer and more concise. > > > > > > > > function foo(array $array) { > > > > assert(array_is_list($array)); // Already know it's an > array... > > > > } > > > > > > > > if (is_array($value)) { > > > > if (array_is_list($value)) { // Already know it's an array... > > > > return serialize_as_list($value); > > > > } else { > > > > return serialize_as_dict($value); > > > > } > > > > } > > > > > > > > Regards, > > > > Nikita > > > > > > I like array_is_list(array $array): bool much better, too. > > > > After seeing the discussion about confusion with potential > > list/vec > types, the potential for confusion with ArrayObject/SplDoublyLinkedList, > > and the likeliness that this will usually be called on values that are > already known to be arrays, > > array_is_list(array $array): bool seems like a better > > option - it's > better to throw a TypeError for objects > > despite the slight inconvenience of potentially needing to rule out > null/false. > > > > I plan to update the RFC/implementation soon. > > The RFC https://wiki.php.net/rfc/is_list and the implementation > has been > updated. > The signature has changed from is_array_and_list($value): bool > to array_is_list(array $array): bool > Thanks, the updated RFC looks good to me. Nikita