Cachet/app/helpers.php

<?php

if ( ! function_exists('elixir'))
{
    /**
    * Get the path to a versioned Elixir file.
    *
    * @param  string  $file
    * @return string
    */
    function elixir($file)
    {
        static $manifest = null;

        if (is_null($manifest))
        {
            $manifest = json_decode(file_get_contents(public_path().'/build/rev-manifest.json'), true);
        }

        if (isset($manifest[$file]))
        {
            return '/build/'.$manifest[$file];
        }

        throw new InvalidArgumentException("File {$file} not defined in asset manifest.");
    }

}