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Date: Sat, 20 Oct 2007 19:39:46 -0400
To: Stanislav Malyshev <stas@zend.com>
Cc: Gregory Beaver <greg@chiaraquartet.net>, internals@lists.php.net
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Subject: Re: [PHP-DEV] Re: Order of class resolution with namespaces and
	autoload
From: chuck@horde.org (Chuck Hagenbuch)

Quoting Stanislav Malyshev <stas@zend.com>:

> This is even better than requiring, and makes the intent very clear. =20
> I don't think it decreases intuitiveness, on the contrary - from the =20
> look of the code it is immediately clear which exception would be =20
> used.

I went ahead and tried to apply this (explicit imports of classes in =20
the same namespace) to the library that I'm working on, and it doesn't =20
work. Here's the same example as before with 1.php and 2.php, but this =20
time we're trying to avoid ambiguity by importing Test::Exception in =20
each file:

1.php:
------
<?php

namespace Test;
import Test::Exception;

throw new Exception();


2.php:
------
<?php

namespace Test;
import Test::Exception;

throw new Exception();


(yes, they are identical; imagine that one defines, say, Test::Runner =20
and the other defines Test::Case, both of which can throw =20
Test::Exception)

Now I run parent.php, which looks like:
---------------------------------------

<?php

function __autoload($class) {
     include './test_exception.php';
}

try {
     include '2.php';
} catch (Exception $e) {
     echo get_class($e) . "\n";
}

try {
     include '1.php';
} catch (Exception $e) {
     echo get_class($e) . "\n";
}



And I get:
----------
$ php parent.php
Test::Exception

Fatal error: Import name 'Exception' conflicts with defined class in =20
/Users/chuck/Desktop/php namespaces/1.php on line 4

This one I can't solve by removing the use of autoload, either - if I =20
include test_exception.php before doing anything, it just fails on the =20
first file that imports it:

$ php parent.php

Fatal error: Import name 'Exception' conflicts with defined class in =20
/Users/chuck/Desktop/php namespaces/2.php on line 4



I can go back to avoiding the names of all PHP built in classes like =20
we had to do before namespaces, but PHP _should_ be able to add new =20
builtin classes without affecting my code - that should be one of the =20
biggest benefits of namespaces. And that's not even talking about how =20
including other non-namespaced code shouldn't be able to affect how my =20
  namespaced code behaves.

-chuck