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To: "'Jessie Hernandez'" <jrhernandez05@gmail.com>
Cc: <internals@lists.php.net>
Date: Tue, 2 Aug 2005 11:16:49 +0200
Organization: bitXtender GbR
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Subject: RE: [PHP-DEV] [PATCH] Namespace Patch, Beta 1
From: dz@bitxtender.com (=?iso-8859-1?Q?David_Z=FClke?=)
References: <FC.AB.04646.C61FEE24@pb1.pair.com>

This sounds awesome. Good job, Jessie. Keep it up!

- David


> -----Original Message-----
> From: Jessie Hernandez [mailto:jrhernandez05@gmail.com]
> Sent: Tuesday, August 02, 2005 6:07 AM
> To: internals@lists.php.net
> Subject: [PHP-DEV] [PATCH] Namespace Patch, Beta 1
> 
> Attached is the latest version of the namespace patch! It finally includes
> namespace imports and it even includes anonymous namespace support. Also,
> the previous bison shift/reduce conflict has been removed. Here is a
> summary of its features:
> 
> - Simple imports: import ns:class1;
> - Import aliases: import ns:class1 as my_alias;
> - Namespace imports: import namespace ns;
> - Anonymous namespaces:  namespace { class file_class{} }
> - Namespace-private classes: namespace ns{ private class prv_class{} }
> 
> Two new functions have also been added to support namespace imports (more
> on
> that below):
> 
> - get_imported_namespaces([$className])
> Returns an array of imported namespaces for the current file. If a class
> name is passed, and this class is currently being autoloaded (also meaning
> that this function is called inside __autoload), then the list of returned
> imported namespaces is based on the file that triggered the __autoload
> call.
> 
> - autoload_import_class($className, $namespaceName)
> Imports a class in a given namespace for the currently executing file (can
> ONLY be used inside __autoload!)
> 
> Imports
> -------
> Imports and namespace imports are handled completely by the user with the
> use of the __autloload function. This means that there are no restrictions
> on class file naming/directory structure. For simple imports, the class
> name will be passed with its full name (including the colons, such as
> "ns:class1"). For namespace imports, only the class name will be called.
> Since the user needs to determine which namespace (or namespaces) a class
> belongs to, the "get_imported_namespaces" function is provided to check
> the
> imported namespaces for the currently-executing file. Once the user is
> satisfied with a match, he/she needs to perform an "import" for this
> class,
> but this needs to be done on the executing file, not the file where
> __autoload is defined. For this reason, the autoload_import_class function
> is provided. A sample usage of both these functions is at
> tests/classes/namespace_autoload.php.
> 
> Namespace-private classes
> -------------------------
> Classes marked as "private" from within a namespace can only be used by
> classes defined in the same namespace.
> 
> Anonymous namespaces
> --------------------
> Classes defined inside anonymous namespaces can only be used within the
> file
> that declared the anonymous namespace.
> 
> 
> I believe the attached patch solves the issues that were presented long
> ago
> for namespaces. Referring to the post by Daniel Cogwill at
> http://www.zend.com/lists/engine2/200304/msg00164.html, the following are
> my answers to the problems he found at the time:
> 
> 1) import-all silently hides local names.
> A: If a global class is defined with the same name as a class in a
> namespace, and the namespace class has been imported in the same script,
> the global class takes precedence. The namespace class can still be used
> by
> using its full name, i.e. namespace_name:class_name.
> 
> 2) Interestingly (and I assume this is simply a bug), functions and
> classes
> behave differently wrt to import-all and duplicate definitions.
> A: Irrelevant in this patch.
> 
> 3) There is no way to hide names from import (i.e. make a name
> non-exportable). This is a fundamental namespace feature, and there is
> already an appropriate keyword (private).
> A: Namespace-private classes are supported, using the "private" keyword.
> 
> 4) The semantic meaning of successive imports depends on their relative
> ordering.
> A: The engine does not attempt to determine which class is included, the
> user decides the most appropriate behavior  inside __autoload.
> 
> 5) The most egregious issue is that an import in an included file affects
> the scope of the including file.
> A: Imports in this patch only affect the file they are in.
> 
> 
> Since I could not find a way to add the tests/classes/namespace directory
> and subdirectories, I zipped them separately, as before.
> 
> Let me know if you have any questions on the attached patch.
> 
> 
> Best regards,
> 
> Jessie Hernandez
>