*The point is not about the possibility of crossing the limit of the array,
but the need for a definition so one can design a method or function whose
behavior aligns with the array capabilities. This need, in fact, became
more noticeable from a design point of view since the introduction of the
iterable pseudo-type.



2018-08-01 16:44 GMT-03:00 Marcos Passos <marcospassos....@gmail.com>:

> It looks like the limit I mentioned, used by some functions, is
> architecture-dependent:
> https://github.com/php/php-src/blob/master/Zend/zend_types.h#L288
>
> Also, that's such a ridiculously large number for the vast majority of
>> people using PHP that hardly anyone ever runs into this limit.
>
>
> The point is not about the possibility of crossing the limit of the array,
> but the need for a definition is one to design a method or function whose
> behavior aligns with the array capabilities. This need, in fact, became
> more noticeable from a design point of view since the introduction of the
> iterable pseudo-type.
>
> No one ever said "this is what will happen if a PHP array exceeds <this>
>> size". Until someone does that, I cannot document it.
>
>
> I cannot disagree more with this statement.
>
> - Marcos
>
> 2018-08-01 16:29 GMT-03:00 Sherif Ramadan <theanomaly...@gmail.com>:
>
>> It's undocumented, because it's considered undefined behavior. PHP arrays
>> implicitly store the number of elements internally as an unsigned 32 bit
>> integer (regardless of architecture). This means that (technically) you
>> can't create an array with more than ((2**31) - 1) elements (or
>> 2,147,483,647 elements). However, PHP won't actually attempt to stop you
>> from doing this! The problem is, once you exceed these number of elements,
>> the integer will overflow, causing undefined behavior (all kinds weird
>> bugs). So we cannot document behavior that was never defined. No one ever
>> said "this is what will happen if a PHP array exceeds <this> size". Until
>> someone does that, I cannot document it. Also, that's such a ridiculously
>> large number for the vast majority of people using PHP that hardly anyone
>> ever runs into this limit.
>>
>>
>>
>>
>> On Wed, Aug 1, 2018 at 2:42 PM Marcos Passos <marcospassos....@gmail.com>
>> wrote:
>>
>>> Whenever you look for more information about the maximum size of an
>>> array,
>>> you find someone saying that "PHP arrays do not have a maximum size, but
>>> the amount of memory available". However, I could not find any excerpt in
>>> PHP documentation that supports that.
>>>
>>> Even if the engine imposes no hard limit on the size of an array, in
>>> fact,
>>> there an inherent limit that is assumed by some functions, and that is
>>> what
>>> I would like to suggest making explicit on the documentation. The lack of
>>> this definition leads to inconsistencies and leaves several open
>>> questions,
>>> including:
>>>
>>>    - If no limit exists, then it's conceptually possible to have an array
>>>    with *PHP_INT_MAX + 1* elements. In that sense, what would be the
>>> return
>>>    of the *\count()*?
>>>    - The function *range* validates the size of the resulting range
>>> against
>>>    the maximum size of the hash table (defined internally as
>>> *HT_MAX_SIZE*),
>>>    and throw an error if it exceeds that value. Is that the limit?
>>>    - he function *array_fill*, in contrast, does not rely on
>>> *HT_MAX_SIZE*
>>>    for validating the size of the result. But, why?
>>>    - The documentation says that omitting the third parameter of
>>>    array_split is equivalent to \count($array). If the maximum number
>>>    representable in PHP is *PHP_INT_MAX*, is the max size the same as
>>>    *PHP_INT_MAX*?
>>>
>>> There are other examples, but I think these are enough to make the point.
>>>
>>> My understanding is that the conceptual limit is *PHP_INT_MAX*, as there
>>> is
>>> no way to represent the size above this value. If so, the interval that
>>> represents all possibles indexes for an array is defined as *0 <= index
>>> <=
>>> PHP_INT_MAX -1*. That definition aligns with all functions that support
>>> negative length as *-PHP_INT_MAX* is equivalent to the start of the
>>> array.
>>>
>>> Could you guys please share your thoughts on this topic?
>>>
>>
>

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