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    <p>1) use __autoload or <a href="http://php.net/manual/en/function.spl-autoload-register.php" rel="nofollow noreferrer">spl_autoload_register</a> to load classes</p> <p>2) use magic methods, to call function when getting unknown property. Following examples demonstrates how to use __get and dynamicaly initialize object only when you use them.</p> <pre><code>//use __autoload to load db and config class when they are called. class db{ function lol(){ echo 'Hello from db-&gt;lol() &lt;br /&gt;'; } } class config{ function lol(){ echo 'Hello from config-&gt;lol() &lt;br /&gt;'; } } //Manager class to use with classes where you want to access other object trough $this class Manager{ private $_instances=array(); function __get($name){ //if instance does not exists, create one if (!isset($this-&gt;_instances[$name])){ $this-&gt;_instances[$name]=new $name(); } //return instance return $this-&gt;_instances[$name]; } } class Some extends Manager{ function f1(){ $this-&gt;db-&gt;lol(); $this-&gt;config-&gt;lol(); } } $some=new Some(); $some-&gt;f1(); //echoes 'Hello from db-&gt;lol()' and 'Hello from config-&gt;lol()' </code></pre> <p>But for accessing global class instances I prefer using following method: Use singleton pattern to access global class trough GloballClass::i() and if global class is not defined use autoload to load that class.</p> <pre><code>class db extends mysqli{ private static $_i; //Access to singleton instance public static function i() { return (self::$_i instanceof self)?self::$_i:self::$_i = new self(); } //class functions function q($q){ echo 'Hello from db-&gt;q()'; } } class config{ private static $_i; //Access to singleton instance public static function i() { return (self::$_i instanceof self)?self::$_i:self::$_i = new self(); } //class functions function somefunction(){ echo 'Hello from config-&gt;somefunction()'; } } db::i()-&gt;q('SELECT * FROM users'); config::i()-&gt;somefunction(); </code></pre> <p>Following is solution inspired by Gordons comment: It uses GlobalClassFactory class to define only one instance of global classes.</p> <pre><code>class db{ function lol(){ echo 'Hello from db-&gt;lol() &lt;br /&gt;'; } } class config{ function lol(){ echo 'Hello from config-&gt;lol() &lt;br /&gt;'; } } class GlobalClassFactory{ private static $_classes=array(); public static function getInstance($name){ if (!isset(self::$_classes[$name])){ self::$_classes[$name]=new $name(); } return self::$_classes[$name]; } } class Base{ function __get($name){ return GlobalClassFactory::getInstance($name); } } class Some extends Base{ function f1(){ $this-&gt;db-&gt;lol(); $this-&gt;config-&gt;lol(); } } $some=new Some(); $some-&gt;f1(); </code></pre>
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    1. POPHP Object Extension $this->some_object->method
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    1. COSubclassing from a general Base class is almost always a bad idea. You are creating a relationship that says `Some` *is-a* `Manager`, when it really isnt. Also, if you are storing the instances as object instances, any class extending Manager will create separate instances just for itself, which in the case of db and config is unlikely to be wanted. Singletons can mitigate this, but since Singletons cannot be instantiated with `new`, the code in `__get` will no longer work. And Singletons are generally a bad idea anyway.
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    2. COYou are right, Gordon, so I created solution where only one instance of every global class is created. But why Singletons are bad idea?
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    3. COYou just exchanged the problem :) How do you create non-Singleton now? Also, you are still creating an *is-a* relationship and now you also coupled the Base class to the factory by hardcoding it into the `__get` method, effectively reducing the Base class to a magic getter. I mean, sure it works, but it's poor design IMO. Try to avoid *global* things.
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