Re: [PHP-DEV] Exceptions and Errors

[Andi Gutmans]

I think the main reason for all of this disagreement, is because PHP 
(pre-exception state) is not consistent with its error levels. As mentioned 
here, sometimes relatively serious errors are E_WARNINGs and some less 
serious errors are E_ERRORs. Now say, we'd map all E_ERRORs (which can be 
recovered from) to exceptions, functionally this would not be very 
problematic because for people not using exceptions they'd still get a 
fatal error and it would allow people who want to work with exceptions to 
take advantage of them. However, as stated the fact that PHP is 
inconsistent with its error levels would probably limit the usefulness of 
such a change because it'd probably lead to quite a few inconsistency.

I think the people here who argue that exceptions suck are quite wrong. In 
most cases, you expect your code to work perfectly. If it doesn't, I don't 
think you usually want it to continue its regular control flow. Rather, 
it'd be easier to catch the exception and give some kind of useful error 
message. Exceptions allow you to get rid of all of those if() statements 
that check function return values (due to it being a headache many 
developers leave those out) and to handle errors in a centralized place for 
logging and outputting a nice error screen. After all they should be used 
for real errors and not for control-flow. I think people who argue that 
exceptions suck probably aren't the people who check every return code of 
their functions or they'd be completely pissed off with that error model.

Personally, I am not sure what my take on this is as I think most of us 
agree that it's a mess and there's no perfect solution. In an ideal world, 
I would prefer to write DB connection/query/disconnection code without 
having to check their return values, and if an error occurs, catch that 
exception and give a meaningful error message. However, it seems that 
finding the right solution for PHP is going to be pretty hard.

Thinking out loud, it might be interesting to think of some automatic 
wrapping API, which could be used in order to use exception based PHP vs. 
regular PHP. However, doing this in a way which is accurate and automatic, 
especially as relying on our current E_* doesn't seem to be a good option, 
would be quite hard.

Andi

--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php