Namespaces and dynamic language features


PHP's implementation of namespaces is influenced by its dynamic nature as a programming language. Thus, to convert code like the following example into namespaced code:

One must use the fully qualified name (class name with namespace prefix). Note that because there is no difference between a qualified and a fully qualified Name inside a dynamic class name, function name, or constant name, the leading backslash is not necessary.

Beispiel #2 Dynamically accessing namespaced elements

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namespace namespacename; class classname { function __construct() { echo __METHOD__,"\n"; } } function funcname() { echo __FUNCTION__,"\n"; } const constname = "namespaced"; include 'example1.php'; $a = 'classname'; $obj = new $a; // prints classname::__construct $b = 'funcname'; $b(); // prints funcname echo constant('constname'), "\n"; // prints global /* note that if using double quotes, "\\namespacename\\classname" must be used */ $a = '\namespacename\classname'; $obj = new $a; // prints namespacename\classname::__construct $a = 'namespacename\classname'; $obj = new $a; // also prints namespacename\classname::__construct $b = 'namespacename\funcname'; $b(); // prints namespacename\funcname $b = '\namespacename\funcname'; $b(); // also prints namespacename\funcname echo constant('\namespacename\constname'), "\n"; // prints namespaced echo constant('namespacename\constname'), "\n"; // also prints namespaced

Be sure to read the note about escaping namespace names in strings.