Extend PHP Class to allow new methods found via __callStatic - php

Question

Looking for a flexible way to allow other developers to extend render methods for a templating system, basically allowing them to generate their own render::whatever([ 'params' ]) methods.
Current set-up work well from a single developer point of view, I have a number of classes set-up based on context ( post, media, taxonomy etc ), with a __callStatic method collecting the calling function which checks if the method_exists within the class, and if so, extracts any passed arguments and renders the output.
quick example ( pseudo-code ):
-- view/page.php
render::title('<div>{{ title }}</div>');
-- app/render.php
class render {
public static function __callStatic( $function, $args ) {
// check if method exists
if ( method_exists( __CLASS__, $function ){
self::{ $function }( $args );
}
}
public static function title( $args ) {
// do something with the passed args...
}
}
I want to allow developers to extend the available methods from their own included class - so they could create for example render::date( $args ); and pass this to their logic to gather data, before rendering the results to the template.
The questions is, what approach would work best and be performant - errors are safety are not a big concern at this point, that can come later.
EDIT --
I am already making this work by doing the following ( pseudo-code again.. ):
-- app/render.php
class render {
public static function __callStatic( $function, $args ) {
// check if method exists
if (
method_exists( __CLASS__, $function
){
self::{ $function }( $args );
}
// check if method exists in extended class
if (
method_exists( __CLASS__.'_extend', $function
){
__CLASS__.'_extend'::{ $function }( $args );
}
}
public static function title( $args ) {
// do something with the passed args...
}
}
-- child_app/render_extend.php
class render_extend {
public static function date( $args = null ) {
// do some dating..
}
}
The issue here is that this is limited to one extension of the base render() class.

Answer 1

A common way (used by Twig and Smarty, for a couple of examples), is to require developers to manually register their extensions as callables. The render class keeps a record of them, and then as well as checking its own internal methods, also checks this list from _callStatic.
Based on what you have already, this might look like this:
class render
{
/** #var array */
private static $extensions;
public static function __callStatic($function, $args)
{
// check if method exists in class methods...
if ( method_exists( __CLASS__, $function )) {
self::{$function}(self::$args);
}
// and also in registry
elseif (isset(self::$extensions[$function])) {
(self::$extensions[$function])($args);
}
}
public static function title($args)
{
// do something with the passed args...
}
public static function register(string $name, callable $callback)
{
self::$extensions[$name] = $callback;
}
}
A developer would make use of this like so:
render::register('date', function($args) {
// Do something to do with dates
});
Full demo here: https://3v4l.org/oOiN6