hooks

There are no limits and no performance penalties. To understand why, you need to understand how all hooks are stored in the WP ecosystem. First of all you need to understand where all hooks are stored and how they do it. All hooks for filters and actions are stored in global variable called wp_filter, yes … Read more

Actions do things. Filters modify things. You do stuff in an action, whereas if you apply a filter, you do not expect any events or actions to occur, other than the modification of the value you’re filtering. e.g. It’s not okay to send an email or save a DB value in a filter, but it … Read more

all is just a string the WordPress developers picked to behave differently than any other hook. When you attach to all, your callback will fire for all other hooks. I wouldn’t spend too much time looking at the source of do_action, just know that: add_action( ‘x’, ‘whatever’ ) will mean whatever fires for do_action( ‘x’ … Read more

Look at wp-includes/taxonomy.php. The actions are: do_action( “create_term”, $term_id, $tt_id, $taxonomy ); do_action( “created_term”, $term_id, $tt_id, $taxonomy ); do_action( “edited_term”, $term_id, $tt_id, $taxonomy ); do_action( ‘delete_term’, $term, $tt_id, $taxonomy, $deleted_term ); do_action( “create_$taxonomy”, $term_id, $tt_id ); do_action( “created_$taxonomy”, $term_id, $tt_id ); do_action( “edited_$taxonomy”, $term_id, $tt_id ); do_action( “delete_$taxonomy”, $term, $tt_id, $deleted_term );