[RFC][Discussion] iterable_to_array() and iterable_count()

Hello internals, I'd like to propose two new functions for PHP 7.3: iterable_to_array() and iterable_count() These functions are supposed to work with iterables (7.1 pseudotype) - both arrays and iterators, unlike iterator_*() functions which only work with iterators. Here's an RFC for this: https://wiki.php.net/rfc/iterable_to_array-and-iterable_count Note that in order to make iterable_to_array() compatible with iterator_to_array(), $use_keys = true behavior is retained. Although this is probably not a good default value as it may cause data loss, using different default value sounds like a way worse option in terms of consistency and compatibility. A PR with implementation for iterable_to_array() is already submitted, iterable_count() to be added soon. Looking forward for your feedback. Thanks! Michael Moravec