<?php

/**

 * Smarty plugin

 *

 * @package Smarty

 * @subpackage PluginsShared

 */

/**

 * evaluate compiler parameter

 *

 * @param array   $params  parameter array as given to the compiler function

 * @param integer $index   array index of the parameter to convert

 * @param mixed   $default value to be returned if the parameter is not present

 * @return mixed evaluated value of parameter or $default

 * @throws SmartyException if parameter is not a literal (but an expression, variable, …)

 * @author Rodney Rehm

 */

function smarty_literal_compiler_param($params, $index, $default=null)

{

    // not set, go default

    if (!isset($params[$index])) {

        return $default;

    }

    // test if param is a literal

    if (!preg_match('/^([\'"]?)[a-zA-Z0-9]+(\\1)$/', $params[$index])) {

        throw new SmartyException('$param[' . $index . '] is not a literal and is thus not evaluatable at compile time');

    }

    $t = null;

    eval("\$t = " . $params[$index] . ";");

    return $t;

}