Re: is_array on objects with ArrayAccess or Iterator implementations

Hi, On Tue, Dec 29, 2009 at 1:27 AM, Clint Priest <cpriest@warpmail.net> wrote: > Etienne Kneuss wrote: >> >> On Tue, Dec 29, 2009 at 12:04 AM, Clint Priest <cpriest@warpmail.net> >> wrote: >>> >>> Unfortunately $x instanceOf ArrayAccess doesn't return true when $x is >>> indeed an array. >> >> Making is_array return true for objects implementing ArrayAccess is a >> bad idea, for two main reasons: >> >> 1) is_array is a type check, and we should still be able to >> distinguish real arrays from objects > > That's true of course, definitely would need to be able to distinguish. > >> 2) ArrayAccess does not guarantee that an object will behave like an >> array, (e.g. you won't be able to use sort() on an object implementing >> ArrayAccess. > > I wonder if this is something that users would be expecting, that any > function which took an array would also take an object that implements > certain interfaces (such as ArrayAccess and perhaps Countable). > >> If, in your case, you want to accept both arrays and ArrayAccess >> objects, I guess if (is_array($v) || $v instanceof ArrayAccess)  is a >> sufficiently good way to check. >> > > I'm finding myself implementing ArrayAccess more and more often because its > so transparent to the consumer.  The reason this came up is because I was > considering returning all arrays from a certain section of my shared code > library always be an array object so that things like > $tblArray->pluck('Value') could be done, rather than array_pluck() type > functionality. > > That got me to thinking about all of the is_array() calls I would need to > replace throughout the codebase. > > Would it be terribly difficult to make objects with ArrayAccess completely > interchangable anywhere an array element would be required by a function? Yes, definitely, it would be a quite big amount of work (basically rewriting every functions dealing with arrays), and the interface that ArrayAccess proposes isn't enough for most array tasks. > -- Etienne Kneuss http://www.colder.ch