Maybe a little late throwing my 2 cents in, but here they are anyway. If you're writing an app that can optionally use a component that is not present, there is nothing conceptually wrong with calling instanceof to determine if that support is present; PHP should not blow up. If the class is not loaded, then the object can't possibly be an instance of it, therefore the operator should return false.
--Wez. On 8/9/05, Andi Gutmans <[EMAIL PROTECTED]> wrote: > You are wrong because __autoload() *is* called and you can load the class > on the-fly. The only problem is if the class does not exist in your code > base, in which case, your application should blow up! > > Andi > > At 07:44 AM 8/9/2005 +0200, Pierre-Alain Joye wrote: > >On Mon, 08 Aug 2005 14:43:25 -0700 > >[EMAIL PROTECTED] (Andi Gutmans) wrote: > > > > > I don't agree that instanceof on a class which doesn't exist > > > should work. It doesn't do so in other languages (or at least not > > > in Java/C++(dynamic_cast)) nor does it really seem to make a lot > > > of sense and be useful. Sounds more like an edge case you have > > > hit with some weird code which can probably be written > > > differently. > > > >You cannot compare PHP with Java and C++ in this case, sorry. They > >work differently for known reason (compiled being one). > > > >If you have a method, which could be a factory, or the behaviors > >depends on which object it gets, you have now 2 choices: > > > >- Accept to live with a possible fatal error > > > >- Include all single classes you are going to check, even if you > > will use none of them. > > > >The 3rd possibility, fix instanceof. > > > > > Today, fetching of classes in the language is very generic, and > > > they have to exist. I see very few cases where this would not be > > > true if you are writing a regular application. In those few cases > > > where you are doing something extremely weird, you can use > > > reflection to introspect an object. > > > >Agreed, that's fetch_class is not opportun for instanceof. My point > >is not about the fetch_class is done but the way instanceof works. > >Reflection is terribly overkilled for such a need, and slow. > > > > > There is no way this would be changed for RC1 (or PHP 5.1) > > > because it's a significant change which would affect many places > > > and not only instanceof. I personally think it shouldn't be > > > changed at all. If you're referencing classes/exceptions in your > > > code that don't exist, then something is very bogus with your > > > code. Don't use a NonExistantException if that could happen, use > > > Exception... > > > >Agreed here too, not related to instanceof though. > > > > > >--Pierre > > > >-- > >PHP Internals - PHP Runtime Development Mailing List > >To unsubscribe, visit: http://www.php.net/unsub.php > > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: http://www.php.net/unsub.php > > -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
