aliases[key] = val;

    if (key[0] == '$')
        variables[key.substr(1)] = val;
    else
        aliases[key] = val;

    std::map<std::string, std::string>::const_iterator i = aliases.find(key);

    string_map::const_iterator i = aliases.find(key);

}
#define IS_VAR_CHAR(c) (isalpha(c) || c == '_')
std::string game_options::expand_vars(const std::string &field) const
{
    std::string field_out = field;
    std::string::size_type curr_pos = 0;
    // Only try 100 times, so as to not get stuck in infinite recursion.
    for (int i = 0; i < 100; i++)
    {
        std::string::size_type dollar_pos = field_out.find("$", curr_pos);
        if (dollar_pos == std::string::npos
            || field_out.size() == (dollar_pos + 1))
        {
            break;
        }
        std::string::size_type start_pos = dollar_pos + 1;
        if (!IS_VAR_CHAR(field_out[start_pos]))
            continue;
        std::string::size_type end_pos;
        for (end_pos = start_pos; end_pos < field_out.size(); end_pos++)
        {
            if (!IS_VAR_CHAR(field_out[end_pos + 1]))
                break;
        }
        std::string var_name = field_out.substr(start_pos,
                                                end_pos - start_pos + 1);
        string_map::const_iterator x = variables.find(var_name);
        if (x == aliases.end())
        {
            curr_pos = end_pos + 1;
            continue;
        }
        std::string dollar_plus_name = "$";
        dollar_plus_name += var_name;
        field_out = replace_all(field_out, dollar_plus_name, x->second);
        // Start over at begining
        curr_pos = 0;
    }
    return field_out;

    field  = str.substr( first_equals + 1 );

    field = str.substr( first_equals + 1 );
    field = expand_vars(field);

    string_map               variables;

    std::string expand_vars(const std::string &field) const;