There are some situations where you might wish to have a post permalink point to a different URL than the default.
This is especially applicable for blog-style “asides” or newsy quick-hits like you might find on the Drudge Report, Daring Fireball, or Kottke.
You can use the WordPress post_link filter to return a custom post permalink.
Note: These instructions assume you are using a PHP customization class to organize your custom code.
public function front_end() {
/* Hooks and filters that affect the front end _only_ go here */
add_filter('post_link', array($this, 'custom_post_link'), 10, 3);
}
public function custom_post_link($url, $post, $leave) {
/* Access the $post object if you want, and then return a new URL */
return [some new URL];
}