I have the following code,
<?php class Templater { static $params = array(); public static function assign($name, $value) { self::$params[] = array($name => $value); } public static function draw() { self::$params; } } $test = Templater::assign('key', 'value'); $test = Templater::draw(); print_r($test); How can I alter this script so I could use this?
$test = Templater::assign('key', 'value')->assign('key2', 'value2')->draw(); print_r($test); You cannot use Method Chaining with static methods because you cannot return a class level scope (return self won't do). Change your methods to regular methods and return $this in each method you want to allow chaining from.
Notice that you should not use T_PAAMAYIM_NEKUDOTAYIM to access instance methods as it will raise an E_STRICT Notice. Use T_OBJECT_OPERATOR for calling instance methods.
Also see:
You shouldn't be using static members:
class Templater { private array $params = []; public function assign($name, $value) : self { $this->params[$name] = $value; return $this; } public function draw() { // do something with $this->params } } $test = (new Templater())->assign('key', 'value')->assign('key2', 'value2')->draw(); 
Just use instance variables and instance functions instead of static ones.
<?php class Templater { $params = array(); public function assign($name, $value) { $this->params[] = array($name => $value); return $this; } public function draw() { echo $this->params; return $this; } } $test = new Templater(); $test->assign('key', 'value')->assign('key2', 'value2')->draw(); print_r($test); 
////////
class Templater { static $params = array();
public static function assign($name, $value) { self::$params[] = array($name => $value); return new Templater; } public static function draw() { return self::$params; } }
$test = Templater::assign('key', 'value')->assign('key2', 'value2')->draw(); print_r($test);
Mixing a static and an instance call like that is poor form in general, omitting that one (unless you give a reason that it needs to be static). The other concept you're working with is call chaining, which is implemented using returns.
class Templater { protected $params = array(); public function assign($name, $value) { $this->params[] = array($name => $value); return $this; } public function draw() { // do drawing w/ $this->params; return $this; } } 
class Templater { public static $params; private static $_instance = null; public static function init() { if (self::$_instance === null) { self::$_instance = new self; } return self::$_instance; } public function assign($name, $value) { self::$params[$name] = $value; return $this; } public function draw() { return self::$params; } } $test = Templater::init()->assign('key', 'value')->assign('key2', 'value2')->draw();