Created Extending (markdown)

Extending.md

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+Flight is designed to be an extensible framework. The framework comes with a set of default methods and components, but it allows you to map your own methods, register your own classes, or even override existing classes and methods.
+
+## Mapping Methods
+
+To map your own custom method, you use the `map` function:
+
+    // Map your method
+    Flight::map('hello', function($name){
+        echo "hello $name!";
+    });
+
+    // Call your custom method
+    Flight::hello('Bob');
+
+## Registering Classes
+
+To register your own class, you use the `register` function:
+
+    // Register your class
+    Flight::register('user', 'User');
+
+    // Get an instance of your class
+    $user = Flight::user();
+
+The register method also allows you to pass along parameters to your class constructor. So when you load your custom class, it will come pre-initialized. You can define the constructor parameters by passing in an additional array. Here's an example of loading a database connection:
+
+    // Register class with constructor parameters
+    Flight::register('db', 'Database', array('localhost','mydb','user','pass'));
+
+    // Get an instance of your class
+    // This will create an object with the defined parameters
+    //
+    //     new Database('localhost', 'mydb', 'user', 'pass');
+    //
+    $db = Flight::db();
+
+If you pass in an additional callback parameter, it will be executed immediately after class construction. This allows you to perform any set up procedures for your new object. The callback function takes one parameter, an instance of the new object.
+
+    // The callback will be passed the object that was constructed
+    Flight::register('db', 'Database', array('localhost', 'mydb', 'user', 'pass'), function($db){
+        $db->connect();
+    });
+
+By default, every time you load your class you will get a shared instance.
+To get a new instance of a class, simply pass in `false` as a parameter:
+
+    // Shared instance of Database class
+    $shared = Flight::db();
+
+    // New instance of Database class
+    $new = Flight::db(false);
+
+Keep in mind that mapped methods have precedence over registered classes. If you declare both
+using the same name, only the mapped method will be invoked.