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function is not described

Composer\Autoload

ClassLoader::register() public WC 1.0

Registers this instance as an autoloader.

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

No Hooks.

Return

null. Nothing.

Usage

$ClassLoader = new ClassLoader();
$ClassLoader->register( $prepend );
$prepend(true|false)
Whether to prepend the autoloader or not

Code of ClassLoader::register() WC 5.3.0

<?php
public function register($prepend = false)
{
    spl_autoload_register(array($this, 'loadClass'), true, $prepend);
}