# Order of class resolution with namespaces and autoload

- Thread: https://externals.io/message/32896
- Original archive: https://news-web.php.net/php.internals/32896
- Started by Chuck Hagenbuch on 2007-10-20T23:39:46+00:00
- Messages: 2
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---

## #32896 — Chuck Hagenbuch — 2007-10-20T23:39:46+00:00

URL: https://externals.io/message/32896#32896

Quoting Stanislav Malyshev <stas@zend.com>:

> This is even better than requiring, and makes the intent very clear.  
> I don't think it decreases intuitiveness, on the contrary - from the  
> look of the code it is immediately clear which exception would be  
> used.

I went ahead and tried to apply this (explicit imports of classes in  
the same namespace) to the library that I'm working on, and it doesn't  
work. Here's the same example as before with 1.php and 2.php, but this  
time we're trying to avoid ambiguity by importing Test::Exception in  
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  
and the other defines Test::Case, both of which can throw  
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  
/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  
include test_exception.php before doing anything, it just fails on the  
first file that imports it:

$ php parent.php

Fatal error: Import name 'Exception' conflicts with defined class in  
/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  
we had to do before namespaces, but PHP _should_ be able to add new  
builtin classes without affecting my code - that should be one of the  
biggest benefits of namespaces. And that's not even talking about how  
including other non-namespaced code shouldn't be able to affect how my  
  namespaced code behaves.

-chuck

---

## #32898 — Gregory Beaver — 2007-10-21T02:27:20+00:00

URL: https://externals.io/message/32896#32898 · In reply to: #32896

Chuck Hagenbuch wrote:
> Quoting Stanislav Malyshev <stas@zend.com>:
> 
> > […]
> 
> I went ahead and tried to apply this (explicit imports of classes in the
> same namespace) to the library that I'm working on, and it doesn't work.
> Here's the same example as before with 1.php and 2.php, but this time
> we're trying to avoid ambiguity by importing Test::Exception in 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
> and the other defines Test::Case, both of which can throw 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
> /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
> include test_exception.php before doing anything, it just fails on the
> first file that imports it:
> 
> $ php parent.php
> 
> Fatal error: Import name 'Exception' conflicts with defined class in
> /Users/chuck/Desktop/php namespaces/2.php on line 4


Hi Chuck,

Turns out you've found a bug in the fix for Bug #42859.  I've attached a
patch for PHP 5.3, and can do the same for PHP 6 later.

Greg