Re: ZendEngine2 / ZEND_CHANGES

how is your book doing :) "Sebastian Bergmann" <sb@sebastian-bergmann.de> schrieb im Newsbeitrag news:<cvssebastian1046082939@cvsserver>... > sebastian Mon Feb 24 05:35:39 2003 EDT > > Modified files: > /ZendEngine2 ZEND_CHANGES > Log: > Initial documentation of namespace {}. > > Index: ZendEngine2/ZEND_CHANGES > diff -u ZendEngine2/ZEND_CHANGES:1.45 ZendEngine2/ZEND_CHANGES:1.46 > --- ZendEngine2/ZEND_CHANGES:1.45 Tue Jan 14 16:29:21 2003 > +++ ZendEngine2/ZEND_CHANGES Mon Feb 24 05:35:39 2003 > @@ -143,7 +143,7 @@ > print $obj->address . "\n"; > ?> > > - * Nested classes (namespaces). > + * Namespaces. > > The Zend Engine 1.0 provided only three scopes: the global > scope, the class scope and the function scope. All scopes but > @@ -153,177 +153,33 @@ > Zend Engine 1.0's scoping methods were inherently limited for > solving symbol name collision problems. > > - The Zend Engine 2.0 introduces the concept of nested classes > + The Zend Engine 2.0 introduces the concept of namespaces > to solve the symbol collision problem by making it possible to > define multiple symbol tables able to contain all types of > - symbols. The Zend Engine is aware of a current class, > - defaulting to the global scope. Each class can contain it's > - own set of constants, functions and static variables. In order > - to access a class's local symbols you can use the self:: class > - accessor, for example, you can do self::$my_static_name = "Hello". > - You can also use the class's name such as > - MyClass::$my_static_name = "Hello". With both constants and > - functions, if you don't specify a class context the current class > - will be searched first and if the search fails then the global > - scope will be searched. If you want to force PHP to only check the > - global scope you can use the main:: accessor. For example, > - main::strlen() to make sure you're calling the strlen() in the main > - scope. You will only need to worry about this if you are defining > - methods which have the same name as global functions. For > - constants you can use the same notation such as self::MY_CONSTANT > - or main::MY_CONSTANT. > - Sometimes you will not want to access constants, functions or classes > - via the class accessor (i.e. MyClass::) because you use them very > - often and are an extremely slow typist. In this case, you can import > - functions, classes and constants from classes with the import keyword. > - It's quite self explanatory and there are a few examples below. > - > - > - * Classes may contain classes. > - > - Example: > - > - <?php > - class DB::MySQL { > - var $host = ''; > - > - function db_connect($user) { > - print "Connecting to MySQL database '$this->host' as $user\n"; > - } > - } > - > - class DB::Oracle { > - var $host = 'localhost'; > - > - function db_connect($user) { > - print "Connecting to Oracle database '$this->host' as $user\n"; > - } > - } > - > - $MySQL_obj = new DB::MySQL(); > - $MySQL_obj->db_connect('Susan'); > - > - $Oracle_obj = new DB::Oracle(); > - $Oracle_obj->db_connect('Barbara'); > - ?> > - > - * Classes may contain constants. > - > - Example: > - > - <?php > - class foo { > - const hey = 'hello'; > - } > - > - print foo::hey; > - ?> > - > - * Current namespace's symbol tables are searched first for > - constants and functions. > - > - Example: > - > - The following code prints "foobar", not "foo", because > - the class constant overrides the "global" constant of > - the same name. > - > - <?php > - define('foo', 'bar'); > - > - class FooClass { > - const foo = 'foobar'; > - > - function printFoo() { > - print foo; > - } > - } > - ?> > - > - * In the scope of a function, the current namespace is that > - of the containing class/namespace. > - > - Example: > - > - <?php > - class FooClass { > - function foo() { > - $this->bar(); > - bar(); > - } > - > - function bar() { > - print "foobar\n"; > - } > - } > - > - $obj = new FooClass; > - $obj->foo(); > - $obj->foo(); > - ?> > - > - This prints "foobar" two times, since a bar() method exists > - in the current namespace. > - > - * It is possible to "import" symbols from one namespace into > - another. > - > - Example: > - > - <?php > - class MyClass { > - class MyClass2 { > - function hello() { > - print "Hello, World in MyClass2\n"; > - } > - } > - > - function hello() { > - print "Hello, World\n"; > - } > - } > - > - import function hello, class MyClass2 from MyClass; > - > - MyClass2::hello(); > - hello(); > - ?> > - > - Example: > - > - <?php > - class MyOuterClass { > - class MyInnerClass { > - function func1() { > - print "func1()\n"; > - } > - > - function func2() { > - print "func2()\n"; > - } > - } > - } > - > - import class * from MyOuterClass; > - import function func2 from MyOuterClass::MyInnerClass; > - > - MyInnerClass::func1(); > - func2(); > - ?> > - > - Example: > - > - <?php > - class MyOuterClass { > - const Hello = "Hello, World\n"; > - } > - > - import const Hello from MyOuterClass; > - print Hello; > - ?> > + symbols. > > - Old code that does not take advantage of namespaces will run > - without modifications. > + A namespace may contain classes, constants, functions and variables. > + The member of a namespace is accessed by prefixing its name with the > + name of the namespace followed by '::'. > + > + Example: > + > + <?php > + namespace Foo { > + class Bar {} > + const aConstant = 'someValue'; > + function aFunction() {} > + var $aVariable; > + } > + > + $o = new Foo::Bar; > + echo Foo::aConstant; > + Foo::aFunction(); > + Foo::$aVariable = 'someValue'; > + ?> > + > + To avoid ambiguities in the '::' resolution there may be no > + global class and namespace with the same name. > > * Unified Constructors. > > >