aaemnnosttv / silk

src/functions.php

<?php

For compatibility and reusability of your code, PSR1 recommends that a file should introduce either new symbols (like classes, functions, etc.) or have side-effects (like outputting something, or including other files), but not both at the same time. The first symbol is defined on line 15 and the first side effect is on line 21.

use Silk\Event\Hook;

if (! function_exists('on')) :
    /**
     * Create and set a new event listener.
     *
     * @param  string   $handle    action or filter handle
     * @param  callable $callback
     * @param  int      $priority
     *
     * @return Hook
     */
    function on($handle, callable $callback, $priority = 10)
    {
        return Hook::on($handle, $priority)
            ->setCallback($callback)
            ->listen();
    }
endif;

if (! function_exists('off')) :
    /**
     * Remove an event listener.
     *
     * If the callback cannot be removed immediately, attempt to remove it just-in-time as a fallback.
     *
     * @param  string $handle   action or filter handle
     * @param  callable $callback
     * @param  int $priority
     *
     * @return bool|Hook        true if immediately removed, Hook instance otherwise
     */
    function off($handle, $callback, $priority = 10)
    {
        if ($removed = remove_filter($handle, $callback, $priority)) {
            return $removed;
        }

        /**
         * If the hook was not able to be removed above, then it has not been set yet.
         * Here we add a new listener right before the hook is expected to fire,
         * so that if it is there, we can unhook it just in time.
         */
        return on($handle, function ($given = null) use ($handle, $callback, $priority) {
            remove_filter($handle, $callback, $priority);
            return $given;
        })->withPriority($priority - 1);
    }
endif;