WordPress at a glance
function is not described

WP_Rewrite::set_tag_base() public WP 2.3.0

Sets the tag base for the tag permalink.

Will update the 'tag_base' option, if there is a difference between the current tag base and the parameter value. Calls WP_Rewrite::init() after the option is updated.

{} It's a method of the class: WP_Rewrite{}

No Hooks.

Return

Null. Nothing.

Usage

global $wp_rewrite;
$wp_rewrite->set_tag_base( $tag_base );
$tag_base(string) (required)
Tag permalink structure base.

Changelog

Since 2.3.0 Introduced.

Code of WP_Rewrite::set_tag_base() WP 5.5.1

<?php
public function set_tag_base( $tag_base ) {
	if ( get_option( 'tag_base' ) !== $tag_base ) {
		update_option( 'tag_base', $tag_base );
		$this->init();
	}
}