std::string to_string(Currency const& currency)
{
static Currency const sIsoBits ("FFFFFFFFFFFFFFFFFFFFFFFF000000FFFFFFFFFF");
// Characters we are willing to allow in the ASCII representation of a
// three-letter currency code.
static std::string const allowed_characters =
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"0123456789"
"<>(){}[]|?!@#$%^&*";
if (currency == zero)
return systemCurrencyCode();
if (currency == vbcCurrency())
return systemCurrencyCodeVBC();
if (currency == noCurrency())
return "1";
if ((currency & sIsoBits).isZero ())
{
// The offset of the 3 character ISO code in the currency descriptor
int const isoOffset = 12;
std::string const iso(
currency.data () + isoOffset,
currency.data () + isoOffset + 3);
// Specifying the system currency code using ISO-style representation
// is not allowed.
if ((iso != systemCurrencyCode()) && (iso != systemCurrencyCodeVBC()) &&
(iso.find_first_not_of (allowed_characters) == std::string::npos))
{
return iso;
}
}
return strHex (currency.begin (), currency.size ());
}
