bbp_check_forum_edit()

function bbp_check_forum_edit() {

	// Bail if not editing a topic
	if ( !bbp_is_forum_edit() )
		return;

	// User cannot edit topic, so redirect back to reply
	if ( !current_user_can( 'edit_forum', bbp_get_forum_id() ) ) {
		wp_safe_redirect( bbp_get_forum_permalink() );
		exit();
	}
}