Ticket #21883: example.php

<?php

function example_setup() {
        plugin()->add_action( 'init', 'hello' );
}
add_action( 'plugins_loaded', 'example_setup' );

function plugin_init() {
        plugin()->do_action( 'init' );
}
add_action( 'init', 'plugin_init' );

function hello() {
        echo 'Hello!'; die;
}