Passing values between functions in PHP

In Laravel it is common to work with functions such as url()->to(string) or redirect()->route(string) where this "second function" ->to(string) extends or returns a value for the first function url() .

How is this done in practice in PHP?

I tried to do something similar but it did not work:

function to($path)
{
    return $path;
}

/**
 * Return the base theme url.
 *
 * @return string
 */
function url(string $path = null)
{   
    if(isset($path))
        $path = "/{$path}";

    return get_template_directory_uri() . $path;
}

Execution:

url()->to('teste')