PHP Autoloader

/**
 * Autoloads files when requested
 * 
 * @since  1.0.0
 * @param  string $class_name Name of the class being requested
 */
function my_class_file_autoloader( $class_name ) {

    /**
     * If the class being requested does not start with our prefix,
     * we know it's not one in our project
     */
    if ( 0 !== strpos( $class_name, 'My_' ) ) {
        return;
    }

    $file_name = str_replace(
        array( 'My_', '_' ),      // Prefix | Underscores 
        array( '', '-' ),         // Remove | Replace with hyphens
        strtolower( $class_name ) // lowercase
    );

    // Compile our path from the current location
    $file = dirname( __FILE__ ) . '/includes/'. $file_name .'.php';

    // If a file is found
    if ( file_exists( $file ) ) {
        // Then load it up!
        require( $file );
    }
}