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function is not described

noindex() WP 2.1.0

Displays a noindex meta tag if required by the blog configuration.

If a blog is marked as not being public then the noindex meta tag will be output to tell web robots not to index the page content. Add this to the 'wp_head' action.

Typical usage is as a 'wp_head' callback:

add_action( 'wp_head', 'noindex' );

No Hooks.

Return

Nothing (null).

Usage

noindex();

Code of noindex: wp-includes/general-template.php VER 5.1.1

<?php
function noindex() {
	// If the blog is not public, tell robots to go away.
	if ( '0' == get_option( 'blog_public' ) ) {
		wp_no_robots();
	}
}