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<?php

if( ! function_exists( 'ccd_tagpages_taxonomy' ) ){
    function tagpages_register_taxonomy()
    {
        register_taxonomy_for_object_type( 'post_tag', 'page' );
    }
    add_action( 'admin_init', 'ccd_tagpages_taxonomy' );
}

if( ! function_exists( 'ccd_display_tagged_pages_archive' ) ){
    function tagpages_display_tagged_pages_archive( &$query )
    {
        if ( ! is_admin() && $query->is_archive && $query->is_tag ) {
            $q = &$query->query_vars;
            $q['post_type'] = 'any';
        }
    }
    add_action( 'pre_get_posts', 'ccd_display_tagged_pages_archive' );
}

?>