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diff --git a/Zend/RFCs/002.txt b/Zend/RFCs/002.txt deleted file mode 100644 index 263c4116c9..0000000000 --- a/Zend/RFCs/002.txt +++ /dev/null @@ -1,169 +0,0 @@ -Title: Zend 2.0 Namespaces -Version: $Revision$ -Status: draft -Maintainer: Stig S. Bakken <ssb@fast.no> -Created: 2001-09-08 -Modified: 2001-09-08 - - -1. Background/Need -================== - -PHP and Zend 1.0 have come to a point where a lot of reusable code is -being written; from simple functions and classes to entire application -frameworks. It is becoming increasingly difficult to avoid symbol -name collisions with the current scoping methods. - -The symbol scopes available in Zend 1.0 are the global scope, the -class scope and the function scope. All scopes but classes may -contain variables, only the class and global scopes may contain -functions, while only the global scope may contain constants and -classes. This means that all of Zend 1.0's scoping methods are -inherently limited for solving symbol name collision problems. - - -2. Overview -=========== - -Namespaces in Zend 2.0 provide a way to manage the symbol collision -problem by making it possible to define multiple symbol tables able to -contain all types of symbols. Zend will get the notion of a current -namespace, defaulting to the current global one. The current name -space may be changed on a file-by-file basis. Symbols in other name -spaces than the current one may be referenced using a new namespace -operator. It will be possible to "import" symbols from one namespace -into another. - - -3. Functionality -================ - -3.1. Namespace Syntax -===================== - -The namespace operator ":" is used to refer to symbols in other -namespaces than the current one: - -Class: Namespace:class -Function: Namespace:function -Static method: Namespace:class::method -Variable: $Namespace:variable -Constant: Namespace:CONSTANT -Class variable: $Namespace:class::variable - -To refer to symbols in the global namespace, symbols are prefixed with -only the namespace operator: - -Class: :class -Function: :function -Static method: :class::method -Variable: $:variable -Constant: :CONSTANT -Class variable: $:class::variable - -Note: $:variable will effectively be just another syntax for -$GLOBALS['variable']. - -A namespace may have a name containing a ":", it is always the last -":" character in the symbol qualifier that is the actual namespace -operator: - -Class: Name:Space:class -Function: Name:Space:function -Static method: Name:Space:class::method -Variable: $Name:Space:variable -Constant: Name:Space:CONSTANT -Class variable: $Name:Space:class::variable - -(Here, the ":" between "Name" and "Space" is part of the name, it is -the one after "Space" that is the namespace operator.) - - -3.2. Defining Namespaces -======================== - -Individual files may define a namespace that will apply to the entire -file. If no "namespace" operator occurs in the file, it will be in -the global namespace: - - 1 namespace HTML; - 2 - 3 class Form { - 4 function Form() { - 5 // constructor - 6 } - 7 // ... - 8 } - -Or with the "nested" name syntax: - - 1 namespace HTML:Form; - 2 - 3 class Image { - 4 var $src; - 5 function Image($src) { - 6 $this->src = $src; - 7 } - 8 // ... - 9 } - -Code executed within the "HTML" namespace may refer to the Form class -as just "Form". Code executed from within other namespaces has to -refer to it as "HTML:Form". The "namespace" statement must occur -before any other statements in the file. - -# [ssb 2001-09-08]: -# Should it be possible to "add" symbols to a namespace by including a -# second file with the same namespace statement? - - -3.3. Importing Symbols -====================== - -It is possible to import symbols from another namespace into the -current one with the "import" statement: - - import * from HTML; // all symbols - - import Form from HTML; // single symbols - - import Form,Table from HTML; // multiple symbols - -There is a potential for name clashes between symols of different -types that have the same qualifier syntax. These are resolved in this -order: class, function, constant. - -Optionally, the symbol type may be explicitly given to import (as -"class", "function", "variable" or "constant"): - - import class Form from HTML; - -And finally, you may import all symbols of a given type: - - import constant * from HTML:Table; - -The namespace with its symbols must already be defined before using -"import". - - -4. Compatibility Notes -====================== - -Old code that does not take advantage of namespaces will run without -modifications. - - -5. Dependencies -=============== - -The class variable syntax depends on this class variables being -implemented in the new ZE2 object model. - - -6. Acknowledgements -=================== - -Andi Gutmans <andi@zend.com> and Zeev Suraski <zeev@zend.com> for -initial ZE2 namespaces proposal - -Dean Hall <php@apt7.com> for the initial symbol qualification syntax |