<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

class haskellTerminal
{
    public $token = null;
    public $value = null;

    public function &evaluate()
    {
        $value =& $this->value;
        if ($value) return $value;

        $token =& $this->token;

        if (is_string($token)) {
            $value =& $token;
            return $value;
        }

        switch ($token[0]) {
        case NUMLIT:
        case STRINGLIT:
            $value = eval("return {$token[1]};");
            break;
        case VARID:
        case VAROP:
            $value = $token[1];
            break;
        default;
            // FIXME
            echo "UNKNOWN TOKEN!!\n";
            var_dump($token);
            echo "\n";
            break;
        }

        return $value;
    }

    public function &getToken()
    {
        return $this->token;
    }

    public function &getTokenString()
    {
        if (is_array($this->token)) {
            return $this->token[1];
        } else {
            return $this->token;
        }
    }

    public function replaceTokenString($string)
    {
        if (is_array($this->token)) {
            $this->token[1] =& $string;
        } else {
            $this->token =& $string;
        }
    }

    public function setToken(&$token)
    {
        $this->token =& $token;
    }
}