NYCPHP Meetup

[Adam Maccabee Trachtenberg]

On Wed, 9 Feb 2005, Hans Zaunere wrote:

> > PHP is not Java. :)
>
> Riiiight... but it does have the same behavior :)

It has similar behavior, but is just different enough to slip you
up. For instance, there's no concept of Checked vs. Unchecked
exceptions in PHP.

> But what if a class should still be instantiated, even if some of
> the arguments are incorrect, or subsequent parts fail for some
> reason?  True, this validation could be done outside of the
> constructor, even in a totally different class that the constructor
> instantiates itself, but this still would prevent the instantiation
> of the original class.

This is a ZE2 limitation. The only way to signal failure from a
constructor is via an exception. Even extensions that never throw
exceptions throw them in the constructor.

If you're concerned a non-essential portion can fail, you can either:

a) Don't throw an exception in that instance, return the object, and
provide developers with a way to check status.

b) Don't place that functionality in the constructor, and provide a
method to update the object with the additional data.

-adam

-- 
adam at trachtenberg.com | http://www.trachtenberg.com
author of o'reilly's "upgrading to php 5" and "php cookbook"
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