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function is not described

spl_autoload_unregister() WP 4.6.0

Unregisters an autoloader function.

No Hooks.

Return

true/false. True if the function was unregistered, false if it could not be.

Usage

spl_autoload_unregister( $function );
$function(callable) (required)
The function to unregister.

Code of spl autoload unregister: wp-includes/spl-autoload-compat.php VER 5.0.3

<?php
function spl_autoload_unregister( $function ) {
	global $_wp_spl_autoloaders;
	foreach ( $_wp_spl_autoloaders as &$autoloader ) {
		if ( $autoloader === $function ) {
			unset( $autoloader );
			return true;
		}
	}

	return false;
}