rfc:namespaces

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rfc:namespaces [2008/09/15 02:02] – pad out "Keywords in namespace names" issue jochemrfc:namespaces [2017/09/22 13:28] (current) – external edit 127.0.0.1
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 The following issues have been put forwards by various members of the php developers group and php users at large, the issues are covered in the following sections: The following issues have been put forwards by various members of the php developers group and php users at large, the issues are covered in the following sections:
-  - 1. global & namespaced code in one file+  - 1. **global & namespaced code in one file**
   - 2. define() & defined()   - 2. define() & defined()
   - 3. Autoload & functions   - 3. Autoload & functions
-  - 4. You can **use** anything+  - 4. You can use anything
   - 5. Importing NameSpace::*   - 5. Importing NameSpace::*
-  - 6. Static methods v. namespaced function ambiguities +  - 6. **Static methods v. namespaced function ambiguities** 
-  - 7. Class constants v. constants ambiguities +  - 7. **Class constants v. namespaced constants ambiguities** 
-  - 8. **use** and includes +  - 8. use and includes 
-  - 9. Importing functions +  - 9. **Importing functions** 
-  - 10. Name resolution order+  - 10. **Name resolution order**
   - 11. Keywords in namespace names   - 11. Keywords in namespace names
   - 12. Namespace must be first declaration in file   - 12. Namespace must be first declaration in file
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 +----
  
 ==== 2. define() & defined() ==== ==== 2. define() & defined() ====
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 <code> <code>
 defined('DEBUG'): YES (expect YES) defined('DEBUG'): YES (expect YES)
-defined('my::test::ns::DEBUG_2'): NO (expect YES)+defined('MY::TEST::NS::DEBUG_2'): NO (expect YES)
 defined('my::test::ns::DEBUG_2'): NO (expect NO) defined('my::test::ns::DEBUG_2'): NO (expect NO)
 defined('my::test::ns::debug_2'): NO (expect NO) defined('my::test::ns::debug_2'): NO (expect NO)
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 +----
  
 ==== 3. Autoload & functions ==== ==== 3. Autoload & functions ====
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 +----
  
 ==== 4. You can 'use' anything ==== ==== 4. You can 'use' anything ====
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 +----
  
 ==== 5. Importing NameSpace::* ==== ==== 5. Importing NameSpace::* ====
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 +----
  
 ==== 6. Static methods/namespaced function ambiguities ==== ==== 6. Static methods/namespaced function ambiguities ====
 +There is an abiguity, from the users point of view between static class method calls and namespaced function calls, essentially it is very difficult to determine (if at all) from the code, even given context, whether **TEST::what();** (from example1.php below) is a static method call or a namespaced function call. The statement could, in this case, be either, and which ever it is the other has been rendered unusable, the code below demonstrates:
  
 +class.inc:
 +<code php>
 +<?php
 +class TEST {
 +    static function what()  { echo __FUNCTION__," in class\n"; }
 +    static function where() { echo __FUNCTION__," in class\n"; }
 +}
 +?>
 +</code>
 +
 +ns.inc:
 +<code php>
 +<?php
 +namespace TEST;
 +function what() { echo __FUNCTION__," in namespace\n"; }
 +?>
 +</code>
 +
 +example1.php:
 +<code php>
 +<?php
 +include './class.inc';
 +include './ns.inc';
 +TEST::what();
 +TEST::where();
 +?>
 +</code>
 +
 +output of example1.php (regardless of include order):
 +<code>
 +TEST::what in namespace
 +where in class
 +</code>
 +
 +There is no way to reference the static method **TEST::what()**, additionally because static method **TEST::where()** is reachable one is left with the potential that the namespaced include will break current code if a **where()** function is later defined in the **TEST** namespace. 
 +
 +//There is a need to disambiguate these two calls, and to be able to call both regardless of the existence of the other.//
  
 +----
  
 ==== 7. Class constants v. constants ambiguities ==== ==== 7. Class constants v. constants ambiguities ====
 +The same ambiguity that exists between static methods and namespaced functions also exists between class constants and namespaced constants.  
 +From the users point of view it not possible to determine, with any easy or certainty, from the code whether **TEST::MY_CONST_ONE** (from example1.php below) is a class constant or a namespaced constant. The statement could, in this case, be either, and which ever it is the other has been rendered unusable, the code below demonstrates:
  
 +class.inc:
 +<code php>
 +<?php
 +class TEST {
 +    const MY_CNST_ONE = 'TEST class CONSTANT ONE';
 +    const MY_CNST_TWO = 'TEST class CONSTANT TWO';
 +}
 +?>
 +</code>
  
 +ns.inc:
 +<code php>
 +<?php
 +namespace TEST;
 +const MY_CNST_ONE = 'TEST class CONSTANT ONE';
 +?>
 +
 +example1.php:
 +<code php>
 +<?php
 +include './class.inc';
 +include './ns.inc';
 +echo TEST::MY_CNST_ONE, "\n";
 +echo TEST::MY_CNST_TWO, "\n";
 +?>
 +</code>
 +
 +output of example1.php (regardless of include order):
 +<code>
 +TEST namespace CONSTANT ONE
 +TEST class CONSTANT TWO
 +</code>
 +
 +There is no way to reference the constant **MY_CNST_ONE** from class **TEST**, additionally because constant **MY_CNST_TWO** from class **TEST** is reachable one is left with the potential that the namespaced include will break current code if a constant **MY_CNST_TWO** is later defined in the TEST namespace, regardless it introduces confusion because one is it possible to retrieve constants from two different 'places' using the exact same prefix/syntax.
 +
 +//There is a need to disambiguate the constants, and to be able to reference both regardless of the existence of the other.// 
 +
 +
 +----
  
 ==== 8. **use** and includes ==== ==== 8. **use** and includes ====
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 +
 +----
  
 ==== 9. Importing functions ==== ==== 9. Importing functions ====
 +It is not currently possible to alias namespaced functions, making them inconsistent with namespaced classes, and forcing users that are working with namespaced functions to always prefix namespaced functions in order to use them. This seems like an artificial limitation that implies functions are a second-class after thought as far as namespaces are concerned, additionally php has never before dictated to users an **OO** over **procedural** style of coding, the current implementation of namespaces seems to imply that **OO** is inherently better. 
 +
 +It is therefore not possible to override built in functions with functions imported from a namespace, which some people has expressed a desire to do ... most notably in the context of template engines, which generally strive to hide as much of the php's syntax from template developers [who generally don't program php] even though the template engine actually uses php syntax/code to expose it's functionality) ... forcing template developers to learn the intricacies of prefixing functions they employ (and there by having to realise that these may clash with static methods!) creates an unnecessary burden.
 +
 +Regardless, it should be possible to import a namespaced function into the current file and use it in the same way one has been accustomed to calling functions.
 +The following examples tries to demonstrate the issue:
 +
 +ns_funcs.inc:
 +<code php>
 +<?php
 +namespace MY::TEST::NS;
 +function foo() { echo "Hello World!\n"; }
 +?>
 +</code>
 +
 +example1.php:
 +<code php>
 +<?php
 +include './ns_funcs.php';
 +// use MY::TEST::NS::foo;
 +use MY::TEST::NS;
 +NS::foo();
 +MY::TEST::NS::foo();
 +?>
 +</code>
 +
 +output from example1.php:
 +<code>
 +Hello World!
 +Hello World!
 +</code>
 +
 +example2.php:
 +<code php>
 +<?php
 +include './ns_funcs.php';
 +use MY::TEST::NS::foo;
 +foo();
 +?>
 +</code>
 +
 +output from example2.php:
 +<code>
 +Fatal error: Call to undefined function foo() in <PATH>/example2.php on line 4
 +</code>
 +
  
  
 +----
  
 ==== 10. Name resolution order ==== ==== 10. Name resolution order ====
  
  
 +
 +----
  
 ==== 11. Keywords in namespace names ==== ==== 11. Keywords in namespace names ====
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 } }
 </code> </code>
 +
 +
 +
 +----
  
 ==== 12. Namespace must be first declaration in file ==== ==== 12. Namespace must be first declaration in file ====
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 </code> </code>
  
-==== 12. Namespaces aren't implemented like in ... ====+ 
 + 
 +---- 
 + 
 +==== 13. Namespaces aren't implemented like in ... ====
 PHP is not <insert your favorite language here>. Granted this is not an issue, but some of you reading this probably need something to smile about after reading the items above! PHP is not <insert your favorite language here>. Granted this is not an issue, but some of you reading this probably need something to smile about after reading the items above!
  
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 additionally a number of patches have already been made available, these are listed below: additionally a number of patches have already been made available, these are listed below:
  
 +==== Issue's 6 & 7 ====
   * http://pear.php.net/~greg/resolvensfuncconst.patch.txt (Greg Beaver)   * http://pear.php.net/~greg/resolvensfuncconst.patch.txt (Greg Beaver)
 This patch addresses the issues regarding resolution ambiguities, as defined in **issue 6. "Static methods/namespaced function ambiguities"** and **issue 7. "Class constants v. constants ambiguities"**. This patch addresses the issues regarding resolution ambiguities, as defined in **issue 6. "Static methods/namespaced function ambiguities"** and **issue 7. "Class constants v. constants ambiguities"**.
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 > >
 > If a fully qualified name is prefixed with function:: or const:: it will only check the namespace function/const.  Here is a test demonstrating how it works: > If a fully qualified name is prefixed with function:: or const:: it will only check the namespace function/const.  Here is a test demonstrating how it works:
- +> 
-ns_071.inc: +ns_071.inc: 
-<code php>+<code php>
 <?php <?php
 namespace foo; namespace foo;
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 ?> ?>
 </code> </code>
-ns_071.phpt: +ns_071.phpt: 
-<code php>+<code php>
 --TEST-- --TEST--
 071: name conflict, function/static method, constant/class constant 071: name conflict, function/static method, constant/class constant
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 </code> </code>
  
 +==== Issue 9 ====
   * http://pear.php.net/~greg/usefunctions.patch.txt (Greg Beaver)   * http://pear.php.net/~greg/usefunctions.patch.txt (Greg Beaver)
 This patch addresses the issues regarding the inability to alias functions to simple names, as defined in **issue 9. "Importing functions"** This patch addresses the issues regarding the inability to alias functions to simple names, as defined in **issue 9. "Importing functions"**
  
 +
 +==== Issue 12 ====
   * http://pear.php.net/~greg/inline_html.patch.txt (Greg Beaver)    * http://pear.php.net/~greg/inline_html.patch.txt (Greg Beaver) 
 This patch addresses the inability to include [html] output prior to the first **<?php** tag, in a namespaced file, as defined in **issue 12. "Namespace must be first declaration in file"**   This patch addresses the inability to include [html] output prior to the first **<?php** tag, in a namespaced file, as defined in **issue 12. "Namespace must be first declaration in file"**  
  
 +To quote the author from his original post regarding this patch: 
  
 +> This is a simple patch that allows files like this to work without parse error.:
 +
 +> main.php:
 +> <code php>
 +<html>
 +<head>
 +<title>template example</title>
 +</head>
 +<body>
 +<?php
 +namespace my::template;
 + 
 +// stuff
 +
 +?>
 +</body>
 +</html>
 +</code>
  
 ===== Miscellaneous ===== ===== Miscellaneous =====
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 ===== Discussions past & present ===== ===== Discussions past & present =====
-**//I will list set of links to archives of all namespace discussions (on internals mailing listonce descriptions and repro-code of the listed issues are inplace//**+Below is a list of links to internals@lists.php.net thread that discuss (amongst others things) namespaces, the list is in reverse chronological order (hopefully) based on the initial post to the given thread and only lists discussion that have occurred in 2008: 
 + 
 +  [[php-internals@122125176711750|the namespace war]] 
 +  [[php-internals@122124674902629|PATCH: allow T_INLINE_HTML before T_NAMESPACE]] 
 +  * [[php-internals@122118945204074|PATCH: updated resolve function/const conflict between namespace/class]] 
 +  * [[php-internals@122118574632627|PATCH: add support for functions to use]] 
 +  * [[php-internals@122126001625094|Please don't start 10 threads day about the Namespace support]] 
 +  * [[php-internals@122114969907530|Scoping of "use" statements and a strategy for 5.3/6.0 release of namespace]] 
 +  * [[php-internals@122110981102381|PATCH: resolve const/function namespace conflicts (Liz take note)]] 
 +  * [[php-internals@122098797532195|namespace function/static method/class constant conflict resolution]] 
 +  * [[php-internals@122018993030061|namespace RFC]] 
 +  * [[php-internals@121920359817682|Namespace Global User Function Calls]] 
 +  * [[php-internals@121776665630615|Inconsistencies in 5.3]] 
 +  * [[php-internals@121626223101585|questions about namespaces, functions vs. closures]] 
 +  * [[php-internals@121615179414749|Include/require into namespace]] 
 +  * [[php-internals@121614847408006|Namespace problem?]] 
 +  * [[php-internals@121502894019535|towards a 5.3 release]] 
 +  * [[php-internals@121447143022557|How bad would it be to say/enforce that namespacing can only apply to classes and not ...]] 
 +  * [[php-internals@121397701404954|simple solution to another namespace conundrum?]] 
 +  * [[php-internals@121233666301819|multiple use]] 
 +  * [[php-internals@121223589228439|Alternative to multiple namespaces per file]] 
 +  * [[php-internals@121199212705823|Name resolution rules]] 
 +  * [[php-internals@121079120018378|5.3 Namespace resolution rules suggestions]] 
 +  * [[php-internals@121071258907404|5.3 and reflection]] 
 +  * [[php-internals@120742574008363|namespace implementation (irritating warning and autoload)]] 
 +  * [[php-internals@120613563032212|RFC: Namespace syntax decision]] 
 +  * [[php-internals@120429739728318|PHP 5.3 Autoload+Namespaces+Functions incorret (atleast wierd) behaviour.]] 
 +  * [[php-internals@120018255502021|Namespace & Type Hinting Summaries?]] 
 +  * [[php-internals@119992382220241|Set default namespace]] 
 +  * [[php-internals@119874502923978|Suggestion: Namespace implementation]] 
 + 
 +//Nothing has been filtered on the basis of relevance BUT some threads may not be listed due to the 'limitations' of the marc.info search functionality!//
  
  
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 the articles & blog posts listed here are (hopefully) in reverse chronological order, please note that older items may no longer be relevant as the implementation has changed since the time the item was published: the articles & blog posts listed here are (hopefully) in reverse chronological order, please note that older items may no longer be relevant as the implementation has changed since the time the item was published:
  
 +  - [[http://forge.typo3.org/wiki/flow3-overview/Notes_on_using_PHP_namespaces|Typo3v5 - Flow3: Notes on using PHP namespaces]]
   - [[http://elizabethmariesmith.com/2008/09/my-five-well-four-and-one-half-issues-with-namespaces/#comments|Elizabeth Smith: four-and-one-half-issues]]   - [[http://elizabethmariesmith.com/2008/09/my-five-well-four-and-one-half-issues-with-namespaces/#comments|Elizabeth Smith: four-and-one-half-issues]]
   - [[http://pooteeweet.org/blog/0/1288#m1288|Lukas Kahwe Smith: Who is using namespaces in PHP already? (including feedback)]]   - [[http://pooteeweet.org/blog/0/1288#m1288|Lukas Kahwe Smith: Who is using namespaces in PHP already? (including feedback)]]
rfc/namespaces.1221444169.txt.gz · Last modified: 2017/09/22 13:28 (external edit)