Re: __toString(), __toArray()

Etienne Kneuss wrote:

Hello, On Tue, Jan 12, 2010 at 11:40 PM, Chris Stockton <chrisstocktonaz@gmail.com> wrote:

Hello, On Mon, Jan 11, 2010 at 8:32 PM, mm w <0xcafefeed@gmail.com> wrote:

cast is not needed in PHP i 'd rather be more interesting in class Obj {

    function __catch($data, $type) {
           //$type [ static_method, method, get_property, set_property]
           if (observed &&  $type == set_property && somevalueIsObserved) {
                 $observer->notify("somevalue::valueWillChanged");
                 $this->somevalue = $data['somevalue'];
                 $observer->notify("somevalue::valueDidChanged");
           } else {
                 continue__call();
           }
    }

}

What? ...

Etienne Kneuss wrote: This is where operator over-loading would be useful however perhaps only explicit casts would make sense here.

I beleive adding a __cast(string $type) would be a useful feature for me, very often I have a toArray method defined. I agree with you that due to unexpected edge cases with operator precedence and general type juggling that __cast should only be called on explicit (cast). I.E.: class Int { public function __cast($type) { return 'int' == $type ? 15 : 0; } } $r = new Int;

This is an exemple where __cast would be very wrong. At the very least, it should return a value that is an inhabitant of the requested type! Do you really want (bool)new Int() to be Int 0? as a result, you have three solutions: 1) have the engine issue an error in case the return value is not compatible 2) provide a return value for every possible types requested 3) throw an exception in case the cast is not handled In the end, it looks way more complicated/magic than _simply_ defining a toArray method that is used whenever you need an object to be an array. You need an explicit cast anyway, so it's (array)$obj vs $obj->toArray().

One difference between these two possibilities is that consumers of an array parameter could consume an object castable to an array whereas it would need to have knowledge that ->toArray() exists in the second scenario.

var_dump($r + 1); // 2 var_dump((int) $r + 1); // 16 var_dump((bool) $r + 1); // 1 -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php